Tag Archives: Handloading for Competition

RELOADERS CORNER: 5.56 NATO: “GO,” “NO-GO”

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This “warning” has been around, and around, for years, but it’s still not always heeded, or understood. Read why and how it matters HERE.

nato stamp
The circle-cross stamp is a NATO-spec cartridge. Your barrel might be marked “5.56” or a more lengthy disclosure referencing its specs. If it’s “.223 Rem.” do not fire a NATO round through it! Your barrel might also not be marked at all. I’ve increasingly seen that. Get it checked. A NATO round will chamber perfectly in a .223 Rem. All exterior dimensions are patently the same, again, it’s the pressure level.

Glen Zediker

I know this is “Reloaders Corner,” but, every now and again at least, I rip open the end of a cardboard factory cartridge box, or five.

I just got finished building up a “retro” AR15 for a new book. Reasons for that are a few, but probably the main one was that I wanted to recollect the one that “got away,” well, the one that I let go. Errant short-sighted judgment, as is common in youthful people. So I built a replica M16A1, circa mid-60s, well, of course, with only two selector stops. At the heart of that rifle is an original-spec barrel, chrome-lined, NATO chamber.

5.56 stamp
This is a NATO chamber stamp. If it’s “.223 Rem.” that’s NOT the same!

That’s leading to this: I opened up a few boxes of “genuine” NATO 5.56 to check it out with, something I honestly haven’t fired for years and years. Dang. That stuff is potent. Over the past several years, the pressure level has increased. Current standard is a little over 62,000 PSI. (NATO is technically measured differently than commercial, but the figures I give here are accurate for comparison.) Compared to SAAMI specs for .223 Remington (commercial) that’s a solid 7,000 difference. (That SAAMI-spec figure has likewise increased over the years, judging from recent test figures I’ve seen respecting commercial .223 Rem.; most references heretofore were max at 52,000 PSI.)

The main impetus for this article, though, came from a recent experience at a local gun shop. I went in search of a sub-sonic .300 Blackout load, and they had one in .300 Whisper. The counter person told me that it was “exactly the same as .300 Blackout, just like .223 is the same as 5.56…” Whoa. Neither statement is true, although Whisper specs are plenty close enough to Blackout that no differences factor in safety or function. However! I didn’t take the time to lecture, but, dang, .223 Rem. and 5.56 NATO are not nearly the same.

First point: do not fire NATO-spec ammo in a rifle with a chamber marked “.223 Remington.” It will, not may, be over-pressure. Reasons have to do with chamber specifications for 5.56x45mm NATO and those for SAAMI-spec .223 Remington. There is a significant difference in the leade or “freebore” cut comparing SAAMI to NATO. That’s the space in a chamber ahead of the cartridge case neck area that leads into the rifling. NATO is radically more generous, meaning “bigger”: longer, more volume. (About 0.150 inches, based on my measurements of bullet seating depths that touch the lands.) There is relatively much more room for expanding gases to occupy in a NATO chamber. In a SAAMI chamber there’s much less room for expanding gases to occupy. The additional pressure is about the equivalent of another full grain (or more) of propellant in the case. Yikes.

high pressure nato
Here’s what happens putting a factory-fresh NATO round through a .223 Rem. chamber. This case is clearly beat. Sure, it might, should, hold up for that firing, but the case is done and the gun took a needless hammering.

nato beat case

There are other little nit differences to pick between the SAAMI and NATO cartridge, and, therefore, chambering specs, but they don’t really factor in a material sense. There’s bound also to be just as many small differences in cartridge dimensions from one maker to the next. I’ve measured enough to tell you that’s true.

Now. What this has to do with reloading (finally, I know) is based on a question I’ve gotten over the years, a concern to some, or at least, as said, a question. And the answer is that you’re better off going with .223 Remington loading data for any ammo intended for “general” range use. That means blasting away on an afternoon. Just because it’s a NATO chamber does in no way mean you’re supposed to run NATO-spec ammo through it! Back it off and enjoy it more.

If you’re relying on a factory-published data manual to give a place to start, or stop (something from Sierra, Hornady, Lyman, or so on) pay very close attention to the test barrel specifications. Clearly, barrel length has a big influence on attaining the published velocities, and some load combinations are going to be worked up using considerably longer barrels than what the most of us have on our AR15s. But the biggest factor is the chamber used in the test barrel. If it’s a SAAMI-spec (sometimes called a “SAAMI-minimum”) chamber then the data should be on the conservative side. Should be. Do not, however, bank on any idea that you should jump straight to the maximum load listed if you’re loading for use in a NATO. There are, always, too many factors that otherwise create more or less pressure (primers, cases, propellant lot, and more).

As time goes by it probably is less likely to encounter a semi-automatic “.223” that’s not a NATO, but it will be marked as such! Clearly, most ammo is used in the most popular guns. That’s not going to be a bolt-action anymore. Make no mistake, though, AR15s exist plentifully that have SAAMI chambers, and I see a lot of aftermarket barrels that are cut with that minimum-dimension reamer.

ANOTHER OPTION
So what’s a “Wylde” chamber? This is a chambering spec developed by Bill Wylde, one of the early and leading pioneers in the quest for improved AR15 accuracy. It is popular and available, especially in aftermarket barrels. What it is, is a chamber that’s in-between SAAMI-minimum and NATO, leaning closer to NATO. Rumors are true: it’s safe to fire NATO-spec factory loads through a Wylde. The Wylde was designed upon the introduction of the heavier competition bullets with the idea of providing more freebore to accommodate the necessarily longer cartridge overall lengths necessary with something like an 80gr. Sierra, but keep the amount of jump to a minimum with shorter bullets fed from the magazine.

This article is adapted from Glen’s books, Handloading For Competition and Top-Grade Ammo, available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com

RELOADERS CORNER: Why Not Flat-Base?

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A better question, given that the vast majority of popular rifle bullets are boat-tail, is why flat-base? KEEP READING

flat base bullet

Glen Zediker

Good question! I have something that at least has elements of an answer.

A boat-tail bullet is the standard for the majority of rifle bullets, and the domineering choice of long-range shooters. Competitive Benchrest shooters favor flat-base bullets. Flat-base is also popular with varmint-hunters: the stellar Hornady V-Max line for good instance.

Hmm.

We all want best accuracy, so why the difference? Consider the overriding characteristic of a flat-base bullet: it’s shorter. Now, since not all flat-base bullets are shorter overall than a same-weight boat-tail (they’re usually not), I seriously need to clarify that!

Clarification: a flat-base can be shorter, and lighter, than it would be if the same ogive or nosecone profile used then added a boat-tail. More: if they’re both the same weight and at least similar in profiles, a flat-base often has a longer bearing area than a boat-tail bullet, again because the boat-tail is sticking down there, or not. These are both a bonus to Benchrest or any other shorter-distance circumstance where utmost precision is the goal. (When I refer to capital-b “Benchrest,” I’m not talking about a shooting rest, but a competitive sport.) Shorter bullets allow slower barrel twists (bullet length, not weight, chiefly governs needed twist). Slower twists offer a miniscule improvement in damping a bullet’s orbital pattern in flight, and considering the likewise near-caliber-size 5-shot groups these folks are after, that matters. Bullets fly in a spiral, like a well-thrown football. Again comparing those with similar profiles, flat-base bullets stabilize faster and sooner than boat-tails, it’s a smaller spiral. Bullets with longer bearing areas tend to shoot better “easier,” less finicky. And, flat-base bullets can provide more cartridge case capacity.

vld and ld compare
Here’s unique. Jimmy Knox of the original JLK Bullets once made flat-base versions of his Davis-designed VLD (very low drag) boat-tails. So this is a .224-caliber flat-base 65gr LD (low drag), which is the same as his 80gr VLD shown with it, just no boat-tail. Why? It was more of a “Why not?” Idea was to provide better downrange performance for those with slower-twist-rate barrels, and to retain the flight pattern and in-barrel characteristics he liked about flat-base (and way on more speed). This idea was popular among some better High Power shooters about 15 years ago.

All those good points make it sound like flat-base provide superior accuracy. They might. By my experience, they do, but! Distance defines the limit of that truth.

The boat-tail provides an aerodynamic advantage, and the farther it flies, the greater this advantage. There are well-founded beliefs that boat-tails are less influenced by gas pressure thrusting against the bullet base. A good and most knowledgeable friend at Sierra told me that a boat-tail has an effectively more concentric radius at the base due to the junction point created by the angle on the tail and the bearing surface. Further, a flat-base, is, in effect, harder to make so that the base will have a radius that’s as concentric with the bullet bearing surface. Manufacture care and quality (related), of course, makes that more or less true or false. If the idea is that a good boat-tail is “easier” to make, that this shape makes the end product more forgiving of manufacturing errors, then I’ll accept that since it’s pretty hard to argue against, but, again, I really don’t think that boat-tail designs simply take up slack in quality tolerances. I’m sho no rocket-surgeon but I know that the tail slips the air better.

LD_ and Hornady 68
Same LD bullet compared to a Hornady 68gr HPBT. The 65 is a tic shorter overall but, because it’s a 15-caliber (!) ogive, way less bearing area (exception to the “rule” big-time) than the boat-tail next to it. The 65 had a higher BC but was über-tricky to get to shoot well. I could get these to just over 3000 fps in a 20-inch .223 Rem. Mostly because of the tiny bearing area.

This can get pounded completely into the ground because adding a boat-tail (and I’ll show a great example of just that) to a similar nosecone also adds weight to the bullet, and that increases BC. It’s not exactly a chicken-egg question, though, because the tail helps otherwise.

barts bullet
Here’s a 52gr boat-tail from Hornady (right) next to a 52gr custom Benchrest bullet. I said the overriding difference is that a flat-base bullet is shorter, but that’s not referring to overall length. A flat-base is shorter than it would be as a boat-tail, if the other dimensions were the same, and usually has a longer bearing area.

You might have also heard said that boat-tails shorten barrel life because the angled base directs burning propellant gases more strongly at the barrel surface. They do, and many steadfastly uphold that as a reason against them. More in a bit. However! Beyond 300 yards, at the nearest, there are no disadvantages in using boat-tail bullets that come close to surpassing their advantages.

There’s another debated advantage of a flat-base and that is they tend to shoot a little better in a barrel that’s about to go “out.” I’m talking about a good barrel that’s pushed the limit of its throat. That one is true too!

And speaking of barrel life, another is that flat-base bullets produce less flame-cutting effect than boat-tails. A barrel lasts longer if fed flat-base. True! Flat-base bullets “obturate” more quickly. Obturate means to “block,” but here it means to close a hole, which is a barrel bore, which means to seal it. The angled boat-tail creates a sort of “nozzle” effect. Can’t much be done about that, though, because when we need boat-tails we need them. That is, however, a big score of help for the varmint hunter.

There is a relatively obscure “combo” out there called a “rebated” boat-tail. This has a 90-degree step in from the bullet shank (body) to the tail. It steps in before the boat-tail taper is formed (they look like a flat-base with a boat-tail from a bullet a couple of calibers smaller stuck on there). It’s common for competitive .308 NRA High Power Rifle shooters, for instance, to switch from the popular Sierra 190gr MatchKing to a Lapua 185 rebated boat-tail when accuracy starts to fall off due to throat wear. Sure enough, the Lapua brings it back for a couple hundred more rounds.

rebated boat tail
Here’s a rebated boat-tail. 115 grain 6mm from David Tubb.

If anybody with heavy equipment making bullets for sale out there is listening: I’d like to see some more rebated boat-tail designs! It is, though, a challenge to make precisely.

So. What? So what? Well, if you are big into small groups, I very encourage some experimentation with flat-base bullets. Again, distance is the only limit to their potential goodness. 100 yards, yes. 200 yards, yes. 300 yards, no!

vld chamfer
One thing is for certain: Flat-base bullets are not nearly as easily seated! Some have an edge-radius, some don’t, but, they are very easy get started crooked, or difficult to get started straight, same effect. I strongly recommend taking steps to square case mouths and use a generous chamfer.

This article is adapted from Glen’s books, Handloading For Competition and Top-Grade Ammo, available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com

RELOADERS CORNER: What I do…

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There are a lot of ideas and options when it comes to loading the “most important” ammo. Here’s the 5-step process I ended up with… READ MORE

dial indicator

Glen Zediker

I spend a lot of time telling everyone else what they should do, and probably more time telling them what not to do, or what they could do… I thought it might be best to tell you all exactly what it is that I do to prepare a batch of ammo for a tournament.

That’s a quick way to show you what, clearly and obviously, matters to me. I admit: I don’t always do all the things that I talk about. A big part of my role here is to pass along information, answer questions before they’re asked, in a way of looking at it. There’s information, and then there’s action, and that’s not a contradiction, to me. For instance, I can tell you all about case neck turning, and metplat uniforming, and many other preparation steps. I have done them all, sometimes do them, but dang sho not always.

Believe me: I have tried everything and much, much more than I’ve ever talked about in these paragraphs.

Following is what I have found works to my satisfaction. Since I’m dealing with a fair amount of cartridges at any one time, there is, no doubt, a time and effort element that’s important to me. In other words, what’s coming next are the things I really think I must do to give my score the best boost I can reasonably give it.

Step One: Get my cases together and size them. I load in 100-round batches, so I start with five boxes, or whatever corresponds to 100 rounds. Without so much as a second glance, I run them all through my full-length sizing die: lube each and cycle it through. If nothing else, most new cases are not nearly ready to load. The case necks are usually banged up, not round, so at the least I’d need to size the inside and outside of the case neck, and I’ve found that, while other appliances will suffice for that, it’s just easiest to use my sizing die.

Step Two: I trim them all. This isn’t done as any matter of safety, just consistency. I set my trimmer to at the least touch each case mouth. This is very important! The next prep steps rely on having cases that are all the same length.

case trimming

Step Three: After chamfering inside and outside (I use a 17-degree on the inside and a standard tool for the outside) I run a flash hole uniformer through each. This is why it’s important to have them all the same height. That way the uniforming tool cuts to a consistent depth.

inside uniformer
After full-length sizing all my new cases (to mostly get the necks shaped up), I trim all the cases to ensure length consistency to start, because the next procedure, inside flash hole deburring, demands it. Shown is from Hornady. CHECK IT OUT HERE

Step Four: Primer pocket uniforming. I run each through this process. Now, I have had some lots of brass that make this normally simple process a chore, and that’s because the reamer is too snug a fit to the pocket. We all know that primer pockets are at their smallest on new cases. That is, by the way, one reason I’ve mentioned that the primer pocket “feel” is a leading indicator after the first firing as to the pressure level of the load. In keeping, there are times when I wait until recycling the first-fired cases before running the uniformer. It depends on how readily the cases will accept the reamer.

primer pocket reamer
Primer pocket uniforming is an important step in my own process, but sometimes I wait until the first-firing. Depending on the tool used, and how much power can be applied to assist, this job can be a chore on a tight pocket. Shown is a Lyman tool. CHECK OUT TOOLS HERE

Note: I consider my “best” ammunition to be that which I load on my once-fired cases. At the same time, I won’t hesitate to use new cases for a tournament (but not for a Regional or bigger event). Over a whopping lot of time keeping notes, my “second-firing” rounds tend to shoot a tad better, but it’s a miniscule amount. That’s why I don’t really sweat over the primer pockets on the first go-around.

Step Five: Roll them all! I run all the cases through a concentricity fixture, aka: spinner, to check runout. I segregate on the following criteria: “flatliners” no visible runout, less than 0.001, 0.001, up to 0.0015, more than that… Five piles. One reason I do 100-round batches is because I need, technically, 88 rounds for a tournament. Since I am using “name-brand” brass, I easily find my 44 prone-event cases that are going to be no more than 0.001 out of round. The remainder are proportioned better to worse for the 200 yard events. It’s not that I don’t think each round matters, because it does, and, honestly, the 200-yard Standing event is what wins a tournament, but that’s way on more on me than the ammo. A case with 0.015 runout is not going to cause a “9.” That case will produce groups way inside the X-ring.

Co-Ax Case and Cartridge Inspector
I segregate using a runout indicator, a tool shown before in these pages. Some argue, logically, that the best way to find cases with the most consistent wall thicknesses is to measure wall thickness, but, my experience has shown that, ultimately, concentricity is the result of wall thickness consistency. Sho is faster. Shown is a Forster Co-Ax Case & Cartridge Inspector

Now. I fully realize that segregating by runout, concentricity (“centeredness”), is not the same as actually measuring case neck wall thicknesses. However! “Flat-liners” are what ultimately result from consistent case neck walls. Since I have also sized the inside of the case neck, not just the outside, the spinner does give an accurate indication of case neck wall consistency.

case segregation
After sorting by runout, here’s what I get, or what I got once… These were graded (left to right) 0.0000 (no perceptible runout), up to 0.0010, 0.0010, 0.0015, and more than that. So, here, there were 37 cases that were at or near the level of neck-turned cases, and another 37 showing only 0.001, but way on easier.

Since it’s often the night before that I’m doing this, spinning is way on faster than measuring…

Then I prime, fill, seat. Get some sleep.

This article is adapted from Glen’s books, Handloading For Competition and Top-Grade Ammo, available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com

RELOADERS CORNER: Pressure Signs

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We usually want the most velocity we can SAFELY get, and here’s all about how to stay safe. Keep reading!

Glen Zediker

I’ve been on the topic of load development — “working up” a load — for the past couple of editions, and, based on the excellent feedback from you all, here’s more. As always, there’s only so much I can write before I have to cut myself off.

I’ve said that velocity is the initial leading indicator of pressure. Velocity, in itself, however, is not a definitive indicator of pressure. I’d like to clarify… The first point is that I am a big believer in establishing a goal for load development, and, for me (and likely most others) that is a velocity. Accuracy is a given! I will never consider a combination that’s not shooting little knots downrange, but accuracy and velocity are not mutually exclusive. I also would never consider a combination that produced very small groups at an unacceptably low velocity, and that’s because I’m shooting (always) beyond 200 yards. The super-accurate low-velocity load gets its bullet shifted that much more in a variable wind, so it’s way on less likely to maintain those small groups.

I want to hit the velocity ballpark I have in mind and that’s why chronograph readings as I’m incrementally increasing the propellant charge are my leading indicator to how close I’m getting. I am also, always, looking for pressure signs on the spent cases — each and every one ejected.

So about those pressure signs…

Primer condition gets first attention.

primer pressure signs
Middle is what I want to see: pretty much a new primer with a nice round dimple in the center. Right, well. Massive pressure! But notice that the primer still shows a radius on the edges and is only a little rougher in appearance, well, aside from the crack…

A primer should have a smoothly dimpled firing pin indention, a shiny appearance, and a visible radius on its edge. If any of those are missing or compromised to varying degrees, there’s your sign… A dull and flattened primer has been abused, as well as one with a pitted or cratered appearance. Clearly, a crack or leak (indicated by black fouling) is way over the limit. After experience, backed up by gauged measurements, you’re liable to find that judging what’s “normal” and “safe” from one rifle can be different from another. I have had individual guns that flattened primers at any point near a safe-maximum charge. And, I’ve had them that just lied. Unfortunately, small-rifle primers don’t show always show pressure signs as reliably as large-rifle primers (structural differences). I’ve had experiences where the primers are all nice and shiny like and then blow out with the next increment. Shame on me for taking it there, and, speaking of: don’t get greedy! That’s one reason a velocity goal is important. Despite what your kindergarten teacher told you, you’re not that special… If you’re reading another 50+ feet per second more than what consensus says you should, better bet you’re over-pressure. “We” went through a lot of that when coated bullets got popular: those changed all the rules for “maximums.”

flattened primer
Here’s flat. My experience has been that large-rifle primers tend to display this indication more so than small. What’s happened is that the primer has flowed quite forcibly to fit the confines of its pocket and the bolt face. It’s also normal for some rifles, but that just means you have to know: pay attention and back off if you see a flattened primer.

The best pressure indicators show at the loading bench.

primer seating
My best “gage” for pressure is seating a primer in a fired and resized case. It’s a feel, gained through comparative experience, but too easy means there was too much pressure.

The reason I suggest (strongly) doing load work-up with new cases is because you then have a baseline. Measure the case head diameter (on the case, not the rim or groove) on the new case and compare it to the fired case. Up to 0.0005 (that’s ten-thousandths) is really high but some say acceptable (not me), and 0.0002-0.0003 is what I’d prefer. Plus, since a new case is at its smallest, meaning it will have a little less capacity than a fired case, you’re getting some assurance that the pressure will likely be a little lower from the same load in subsequent reuses of that case.

All dimensions are at their minimum in a new case. Primer pocket expansion is related to case head expansion. I get (what’s proven to be) a very accurate indication of pressure based on the resistance to seating a primer in that resized case. You have to use a priming tool that gives adequate feedback (meaning low leverage) but if the primer just slips right back in, that load was over-pressure. In a more extreme circumstance, the primer won’t stay seated. Yes. I have seen that. Shame on me, again.

Finally, a new case easily points out the difference between a “pressure ring” and a “sizing line” that can show just above the case head along the case body. A bright ring there indicates excessive stretching (a sizing line comes from the die reducing that area, and is perfectly normal). That “pressure ring” sign is also likely an “improper headspace” sign, but that’s another article.

pressure ring
Here’s a “pressure ring.” This poor old fellah used to be a brand-new Lake City Match case. I suspect there was some issue with this rifle’s headspace, but if you see this bright stretch mark, red flag it! It means the case is going to crack right there next use (called an “insipient head separation”).

Pierced Primers
This is a common malady on AR-platform guns, and especially on the big-chassis versions (SR-25, AR-10, and similar). Pressure both isn’t and is the culprit and the solution. Lemmeesplain: What causes the pierce is a firing pin hole that is too large. It is not the fit of the firing pin tip to the hole! An engineer can explain it, but it has to do with surface area covered by the firing pin hole, and then along with it the surface area of the primer. Simply: the firing pin hole turns into a cookie cutter. A primer pierce creates all manner of ills, including wrecked firing pins, gas flow through the charging handle area (where your face is), and abrasive debris scattered throughout the lower interior, including the trigger parts.

firing pin hole size
Blueprints call for a 0.058-inch diameter firing pin hole on an AR15 bolt. If the hole is too large then primer structural failures (pierces) will, not can, rear up. Too big is anything more than 0.062 inches, and I’ve seen plenty bigger than that. I use machinist’s drill bits to quick-check bolts: 1/16 (0.0625) and #53 (0.0595). If the first fits the hole, find another bolt. If the #53 won’t go, use that bolt with confidence.
pierced primer
Notice that this primer doesn’t really show excessive pressure signs. Just has a hole in it…

Excessive pressure gets blamed for a pierce but what’s really going on there is that it’s not certain that amount of pressure would be judged as “excessive.” It’s just gotten high enough to bring on this result. So, yes, lightening the load will stop the piercing, but, in my experience and that of many others, the pierces can start happening before reaching what most might agree on is a max load. I say that because “we” are all shooting about the same bullet/primer/case/propellant combinations in NRA High Power Rifle (with respect to Service Rifle division AR15s, for instance). Seeing pierced primers before hitting the proximity of competitive velocities points to “something else,” and that is the firing pin hole.

In a truly over-pressure load, the primer can crack or blow slap out, but it won’t pierce.

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

RELOADERS CORNER: 3 Helps For Easy Load Work-Ups

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Read this before you start the process of working up a load for your new rifle! It could save you huge amounts of time and money… Find out more!

Glen Zediker

Spring is around the corner. Well, if you walk way out into the street and squint really hard you can at least think you see it… Well it’s coming soon enough, at least, now’s a good time to get ready.

I never have been big on the personal value of published load data. The data I’m referring to is that from propellant and other component manufacturers, and also from articles done by independents. I think all such information, at most, provides a place to start, and it also gives some ideas on tendencies and cautions, and provides means for comparisons. But. I don’t think it can be taken straight to the loading bench with any guarantee of success, or of attaining “advertised” performance. And I say that not because I don’t think these folks don’t know what they’re doing. They do! It’s because, after way more than enough experience in proving myself right, I can tell you absolutely that their rifle is not your rifle! Neither, necessarily, are their propellant, primer, case, or bullet. Always take careful note of the barrel and components used for any published test data, and compare them to yours. In later comparisons of my notes with published data, sometimes I’m higher, often times I’m lower, and enough times I’m way lower… That’s the main concern there.

It’s not at all difficult to learn to develop your own loads, to essentially write your own loading manual.

To do this efficiently, you need to learn to load at the range. Right, right there near to where you’re testing. An unremarkable investment in a few tools and a little creativity can provide a way to take your show on the road.

Lee press mounted outdoors
You don’t have to invest a fortune to take your show on the road. A C-clamp and one of these little Lee Reloader presses is all you need! And a good powder meter. One with a clamp is handiest, or just mount it to a piece of wood and clamp that down (even a pickup tailgate works just fine). One clamp is adequate on the press since bullet seating is all in the “down” direction and not much force is needed.

The reason to do this is because it provides a way to precisely chart results. It’s a more reliable and accurate way to proceed. Otherwise, the option is to load varying charges at home and then see what happens at the range. That’s okay, but not nearly as good as on-the-spot experiements. Plus, you won’t have left over partial boxes of poor-performing rounds. It’s more economical and way on more efficient.

The preparation part, and this is what you might spend the remaining cold month or two working on, is, first, to get the tooling ready and, second, and most important, to start making notes on your powder meter.

Important: To be able to work up at the range, it’s mandatory that you’re using a meter that has incremental adjustment. Either a “click”-type “Culver”-style insert or, at minimum, a micrometer-style metering arm. You’ll be relying on the meter, not scales, to progress upward in propellant charges, and you absolutely have to know what the values are for each increment using the different propellants you plan to test. That is where you’ll be spending time prior to doing your homework. It’s well worth it! It can be a nightmare trying to get scales to read accurately outdoors, including the digital type.

Harrells meter mounted outdoors
I map out the incremental values of each click on my Harrell’s meter adjustment drum with the propellant I’ll be testing, and it’s really easy to step up each trial with confidence. I carry the whole kit in a large tool box.
Harrells meter close up
This is a Culver insert. It’s a huge help in following this process. It’s precise and repeatable.

Equipment List and Set-Up
When I need to do load work, I size, prep, and prime new cases and put them in a cartridge carrier (usually a 100-round box). I then pack up my little press, seating die, my meter, some cleaning gear, C-clamps, and my propellants. The press and meter and cleaning gear go in a tool box. I usually carry the propellants in a picnic-type cooler. And, very importantly, my chronograph. A notebook, some masking tape, and a sack lunch… I might be there a while.

Always (always) use new cases for load work-up.

When I get to the range, I’ll clamp-mount my press and meter to a bench, get out all the rest, and set up the chronograph. Take a target downrange and tack it up. I test at 300 yards, unless the load is intended for shorter-range use. I initially test longer-range loads at 300. Maybe I’m lazy, but longer-range testing is a tad amount more tedious. I’ll come back for that after I have a contender or two.

Working Up The Load:
The reason it’s a “work-up” is clear enough: we’re almost always looking to get the highest velocity we can, safely. High velocity, or higher velocity, is usually all-good. Shorter flight time means less bullet drift and drop, and a harder hit.

So working up means increasing propellant charge until we’re happy: happy with the speed and also that the cases will still hold water. (And more about that next time…)

blown primer
Keep track of the cases in the order they were fired. This helps later on when the effects can be measured. This little outing here, though, didn’t require a gage to cipher: a tad amount hot on that last little go around (last case bottom row on the right). Thing is, I didn’t load a whole boxfull of those chamber bombs to take with me, and that’s the beauty of loading right at the range.

Very important: it is vitally necessary to have established a goal, a stopping point, prior to testing. That is one of the functions of published data. That goal is bound to be velocity, not charge weight. And that, right there, is why you’re working up at the range: you want to get “advertised” velocity and need to find the charge weight that produces it.

I work up 0.20 grains at a time. Sometimes it’s more if I’m reading an unuseably low velocity on the initial trial. Since my meter has a “Culver”-style insert, which I trust completely, I reference its number of clicks in my notes rather than the grain-weights (a Culver works like a sight knob, and reads in the number of clicks, not the weight itself). I check the weights when I get back, and I do that by clicking to the settings I found delivered, and then weighing the resultant charges. Otherwise, just throw a charge into a case and cap it with masking tape (clearly labeled).

It’s not necessary to fire many rounds per increment. “Mathematically” 3-5 rounds is a stable enough base to reckon the performance of one step. Of course, I’ll be shooting more successive proofs-per-trial once I get it close. Some folks, and especially competitive shooters, wear out a barrel testing loads. That’s not necessary.

Here are 3 things I’ve found over the years to better ensure reliable results. Learned, of course, the hard way.

1. Limit testing to no more than one variable. I test one propellant at a time, per trip. If you want to test more than one on one day, bring the bore cleaning kit and use it between propellant changes. Results are corrupt if you’re “mixing” residues. Same goes for bullets. Otherwise, though, don’t clean the barrel during the test. I fire my most important rounds after 60+ rounds have gone through it, so I want a realistic evaluation of accuracy and velocity.

2. Replace the cases back into the container in the order they were fired. This allows for accurate post-test measurements. Use masking tape and staggered rows to label and identify the steps. I use 100-round ammo boxes because they leave enough space for the tape strips.

3. Go up 0.20 grains but come off 0.50 grains! If a load EVER shows a pressure sign, even just one round, come off 0.50 grains, not 0.10 or 0.20. Believe me on this one…

Check out chronographs HERE
Take a look at suitable meters HERE

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

RELOADERS CORNER: Neck-Only Case Sizing

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Neck-only resizing is an option for the bolt-action owner. Here are some ideas on why it works, and when it works best… Keep reading!

winchester bolt action
Neck-only sizing is for bolt-actions ONLY.

Glen Zediker

Cartridge case re-sizing is one of those topics that draws lines and forms camps. I am a big believer in full-length sizing, for any action type or use, and just saying that immediately draws argument.

Before getting into the “whens” and “whys” respecting full-length or neck-only sizing, here’s one that I think is an absolute: cases for reuse in a (any) semi-automatic should be full-length sized; neck-only sizing is only for bolt-actions. Having established that, all this next really only relates to what’s possible with a bolt-gun.

Backing up a bit: a “full-length” sizing die is one that returns the cartridge case body (and shoulder, if adjusted to do so) to near-to-new dimensions. A “neck-only” sizing die doesn’t touch the case body (and may or may not be able to touch the case shoulder). A full-length sizer also sizes the case neck, and, normally, the entire height of the case neck cylinder. A neck-only die can be adjusted to contact the height of the neck cylinder in various amounts.

hornady neck sizer
A neck-only sizing die doesn’t touch the case body, so there’s no reduction in case body diameter. This die can be adjusted to contact the case shoulder, and setting back the shoulder may still be necessary. Make sure you check cartridge case headspace!

The idea behind a neck-only die is to preserve fired case dimensions: make the case a closer mirror of rifle chamber dimensions. One advantage of neck-only sizing comes to those who expect, or need, to get a good many loadings from their cases, since this approach minimizes case stretching on subsequent firings.

However, the primary flag waved by neck-only fans says that it produces the best accuracy, and that full-length sizing is a compromise, favoring function over accuracy. I do and don’t agree, and the rest of this article I hope will clarify what I just said…

The reason I do and don’t agree is that I know folks who cannot get a good group unless they neck-only size, and I know other folks, and I’m one of them, who get very small groups following what many would say is “over-sizing” their cases.

forster neck sizing set
Here’s a nice set for neck-only sizing. The “bump” refers to the capacity to also contact the case shoulder to control its dimension, if wanted.

I believe that the main influence in realizing the virtues of neck-only sizing has a whopping lot to do with the rifle chamber. Specifically, factory-made, off-the-shelf bolt-actions tend to have relatively more generous chamber dimensions, as will many older surplus-sourced rifles. “More generous” is in reference to the tolerances established for the SAAMI blueprint for the cartridge. This is (wisely) done to help ensure that any and all factory ammo will chamber and fire, and also to help ensure general and all-around feeding reliability. Additionally, it’s common to find some (slightly) oval chambers in factory guns; that has a lot to do with the freshness of the tooling when that chamber was cut. It’s even more common to find them that are off-center.

Purpose-built bolt-action competition rifles, such as those constructed for use in NRA High Power Rifle competition, are custom-chambered* and, while few will use what we might call a “tight” chamber, it’s not likely to encounter one on the larger end of acceptable dimensions.
*”Custom,” here, doesn’t mean they are each unique, it just means that they are done by hand employing a precision-made reamer and therefore are what they ought to be, or we sure hope so. And they don’t tend to be overly generous in (any) dimensions.

neck sizing bushings
If you’re going to go, go all in: dies with interchangeable bushings let you control case neck diameter, adding another measure of control, and even less working and re-working of the brass.

So, in the circumstance where we have a chamber that’s a tad amount big and a cartridge case that’s been manufactured to (usually) the smaller end of SAAMI-set standards, that case will endure more expansion, in all directions, than if it had been in a tighter chamber. Sizing only the case neck to accept and retain another bullet, as said, reduces the subsequent expansion that will occur the next firing, but also, and this is likely if there is an accuracy improvement, the otherwise un-sized case might then be sitting more centered in the chamber. And one reason for that is, if the rifle is equipped with a plunger-style ejector (Remington 700 style) that will bear against one edge of the head of the chambered round, pushing the cartridge off-center, askew. (This ultimately creates another undesirable condition, a warp in the case, and we’ll talk about that another time.)

So, a little bigger case returning to a little bigger chamber likely has a little better chance of getting centered, and I truly believe that is why neck-only sizing can be a help to accuracy for a bolt-action. However! A dimensionally-correct case returning to a dimensionally-correct chamber will perform just as well on target. Full-length sizing a case for reuse in a rifle with what I call a “standard” chamber (which is really running a little closer to the minimums established by SAAMI) also makes for good groups. We prove that every High Power Rifle tournament.

Advice: If you notice your bolt-action doesn’t shoot too well with factory loads, neck-only sizing should pay off and is well worth a try. Do, however, make sure to gauge the cases as is often discussed in Reloaders Corner, and, specifically, cartridge case headspace. If the bolt isn’t closing easily, that’s liable to be the culprit right there: shoulder has gotten too tall.

If you’re running a factory bolt-action, by all means try neck-only sizing. If you want to compare results to full-length sizing, just make sure you’re doing that operation right.

david tubb
Now. Don’t go getting the idea that full-length sizing can’t shoot well. Here’s a 1000-yard prone group at the hands of David Tubb, originator of the 6XC cartridge. Tubb sets case shoulders back 0.002 inches, runs 0.004 case neck tension, and full-length resizes using what amounts to a “small-base” die (additional 0.0005-inch reduction at the case head). He’s also not shooting a factory chamber. (Photo note: the yellow pasters were sighters; red pasters indicate record shots).

Check HERE and HERE to get started…

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

RELOADERS CORNER: What Matters…

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Don’t lose sight of the basics when making tool, dimensional, or load choices. Here are four unchanging “musts” to make your results the best they can be. READ ON!

moly coated bullets
Bandwagon! I jumped on this one as did a whopping lot of others. Moly coating got a huge amount of attention and, indeed drastically improves bullet performance. The furf died down, though, after we discovered it had its share of problems (some were and some weren’t willing to accommodate or work around them). I still use coated bullets but now it’s Boron Nitride.

Glen Zediker

I have been basing some of my topics for this department on correspondence, and here’s another. Someone wrote asking me for a compare/contrast on the two handloading-specific books I’ve written, and the essential question revolved around whether or not the older of the two had been “updated.” Concerns were over inclusion or exclusion of new tools and propellants, and other components, and reloading techniques: essentially whether the newer book was better just because it was newer. Hmm… I thought long and hard about all that.

My answer, strongly self-paraphrased, was that there were always going to be new tools and propellants and bullets and cartridges and primers, but “what matters” in learning how to make ammo gin (accurately and safely) hasn’t really changed. Those who know my work over the past twenty-something years know I’ve never been eager to step up on a soapbox and proclaim coronation of the latest-greatest propellant, bullet, or even cartridge king. Instead, I’ve done my best to help folks learn how to judge merits and values of new things, based on a thorough understanding of all the old things. But this isn’t about me and it’s not just shameless self-promotion. It’s an overview of what I really think matters: it’s an effort to put into perspective the potential merits of all the new things.

full length sizing die

case neck sizing
Choosing the appropriate case and neck sizing die, and then learning how to correctly adjust it, for the needs at hand, which really means for the rifle the ammo will be used in, is another essential element in good loading.

For me, the four most important things to achieve with a handload are, one, that the case has been sized correctly and appropriately for the rifle; two, that care has been taken to ensure that the round is concentric (more in a bit); three, exercising some discretion in bullet velocity (also more in a bit); and, four, taking steps from reloading to reloading to maintain consistent performance.

Then there is an almost never-ending slew of finer points within all these points. And one ton of tools.

What I “know” about a load combination hasn’t come from one afternoon at the range. It’s often come from years. I have seen a whopping lot of bandwagons competitive shooters have jumped onto and off of. Newly hitched wagons are still rolling strong, departing continually. It is very important to have a set of components and processes and load structures to fall back on, which really then means a set that you can move forward from.

concentricity fixture
One of the “big four” goals I set for handloads is concentricity, run-out. Most of the tool and die upgrades I ever suggest making, as well as many case-preparation steps, seek to improve the straightness and centeredness of a loaded round. “Start in the center, finish in the center.”

I look at new things from a perspective of how and how well I can apply one of them to satisfy the same old needs. These needs are a filter, more or less, that helps determine if the new things are indeed improvements, or just new.

I am a competitive person. Our club CRO, Col. Floyd, once announced to the crowd at a local High Power Rifle tournament that I could smell gold-plated plastic through four feet of reinforced concrete… I admit to the truth in that. So, I am in no way suggesting that new things aren’t good, that we should all stay only with what we know. I’m always looking for ways to do better; but for me it’s not been so much trying something new, but rather taking another step using what’s been working pretty well for me thus far. That usually involves more focus on consistency.

I have a lot of stories about ultimate failures eventually resulting from initially wild successes, including lost championships, but the only value telling any of them would have is to make me sound way too old school. They are, again, never (ever) taken to mean that new things aren’t worth pursuit. Just shoot a lot of it under varied circumstances before packing it up along with the suitcase to attend a big event.

Back to setting down some tangible point to all this: most tool choices and case preparation steps I take have a goal of improving loaded round concentricity, which is to say centeredness or straightness. No doubt about it, a bullet looking dead center into a rifle bore is going to shoot better than one that’s cockeyed.

Cases with more consistent neck wall thicknesses, sizing die designs, and bullet seater designs can either enhance or detract from concentricity. Likewise, operations like outside case neck turning are done ultimately to improve concentricity. It matters!

The comment earlier about not getting too greedy for speed gets preached a lot by a good many, and the reason is avoiding anything that’s edgy. “Edgy,” to me, means something that’s going to take a turn for the worse on a day that’s 20-degrees warmer, or (in the case of the lost event mentioned earlier) 20-degrees colder.

pressure check carrtidge cases
Don’t get greedy on speed! An essential component in handloading success is consistency, predictability. Find a “tolerant” propellant, which means it demonstrates flexibility: shoots well at a little lower-than-maximum velocity, and shoots the same at different temperatures. No matter how small the groups were in testing, if pressure starts spiking due to some unaccounted for change those great test groups are likely to open up.

The best advice I can offer on this is, first and most obvious, use a little discretion working up a load to a ceiling higher than what equivalent-spec factory ammo can produce. It can take more than a few case and primer inspections to know if a “max” load is truly safe. Next is to get to work on finding a propellant/primer combination (mostly propellant) that’s showing good accuracy at less-than-max velocities. By that I mean I will not trust anything that seems to shoot well only when it’s running “hot.” Accuracy is, after all and always, what ultimately defines success.

(Since this piece is kind of a “year-end” thing, I plan to start the new year up fresh with a whopping lot more about specific new (and old) things that will help ensure you’re getting the most you can from your time spent at the loading bench.)

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

RELOADERS CORNER: 4 Steps To Improve Standard Die Performance

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It’s easily possible to improve the alignment and concentricity of a die set, and the result is getting closer to perfection in your ammo. Here’s how…

Glen Zediker

Last time I wrote about some problems some dies can have. A couple of those things mentioned had a thing or two to do with preparation and setup, and I said then that “next time” I’d address a few ways to improve the results from the dies you already have. So here it is, sizing die first:

Many of the parts that make up a die, including the die body itself, have threaded couplings to allow for adjustment. Well, threads have gaps and that means there’s some amount of free movement afoot, or “afloat” more correctly. If there were no gaps between threaded surfaces then there would be no threading possible. To see it, loosen a locking or jam nut from a die part, the seating die or decapping stem for instance, and wiggle the part. It wiggles… Taking steps to, at the same time, take out that play and improve parts alignment pays off.

ONE: Let the shellholder float. One of the easiest mods to make to improve all die ops is to remove the apparatus that secures the shellholder into the press ram. It’s usually a wire spring clip. Pliers get it gone. Now the shellholder is free to slip in and out, mostly out, of its slot in the press ram, and an appropriately-sized O-ring banded around the slot area keeps it secure. Head to a real hardware store and find one easy enough. This mod has done two things: one is that the spring clip usually cocks the shellholder so it’s not sitting flat and flush with the ram top, which means neither is the case it’s holding, so now it is; and, two, there is now a self-centering action since the shellholder is free to move a tad. Always keep in mind that we’re dealing with small “tads” (0.001s of inches) and even though it might not be visibly noticeable, this floating setup will result in better alignment.

shellholder clip
Here’s an easy trick that will, not may, improve alignment in die ops. The ultimate result from all these steps is a more concentric round of ammunition, and most seem to think that’s worthwhile… It is.

TWO: Flatten the die lock ring. The next little help is to get the die body and press ram as closely aligned as we can. There’s a lot of gap resultant from the helix of 14-pitch threads. After adjusting the die body downward to produce the amount of case shoulder set-back you want, run a case fully into the die and, holding pressure (lightly, not forcibly) down against the press handle, secure the locking ring. This will ensure that the die is sitting “flat” atop the press. Then ONLY install and remove the die using the locking ring itself! Never the die body. By the way, and this actually is important: I don’t like lock rings that secure via a set screw; I prefer those that offer a clamping-style effect. The little set screw will lever against the angled threads on the die body and that, alone, can tilt the lock ring.

handling die by lockring
Once you get the dies secured as outlined here, handle them ONLY by their lock rings. That ensures all the careful prep stays intact. It also means no change of altering the die height, an asset toward maintaining correct case shoulder set back and also consistent bullet seating depths.

If you’re using a standard-form full-length sizing die, it will have an expander ball or sizing button (either term applies the same, just varies with who’s literature you’re reading). This part is mounted to the decapping stem and functions to open up the inside case neck after the case neck has been outside-sized by the die interior area. Depending on the difference in diameters between the newly-sized case neck inside diameter and the sizing button diameter, that’s more or less stress and friction the neck endures.

clamp-style lock rings
I use clamping-style die body lock rings, like these from Forster. Those with a set screw can tilt the lock ring when the screw tightens in against the angled threads.

I’ve talked more than a few times about the value of polishing the expander to reduce friction, but you still need then to make sure it’s sitting dead center within the die. So…

THREE: Align the expander ball. There’s a little bit of “feel” involved in this step, but it’s not hard to develop. The idea is to tighten the locking screw that secures the decapping stem against movement while the expander ball is captive in the sized case neck. After adjusting stem height (and, by the way, noticing the relatively huge amount of free movement the stem has) run a case up fully into the die and then retract it until you feel the expander engage within the case neck. Stop there. Now apply a little pressure against the press handle going the other direction (as if running the case back up) as you tighten the lock ring on the expander stem. That just set the expander in the center. If you have the tooling to determine this, select a case that represents your better examples of case neck wall thickness consistency for ultimate results.

 

expander ball adjustment
When it’s possible, and it usually is, secure locks for the pieces-parts when they’re doing their jobs. For instance, tightening the lock on a decapping stem when the expander is holding inside the case neck helps bring the stem into centered alignment, and the expander along with it.

Moving to the “other” die, the seater, the first step is the same as for the sizing die: flatten its seat atop the press, and that’s done pretty much in the same as for the sizing die. Instead of running a case into the die, though, I set an adequate number of flat washers atop the shellholder to bear some pressure against the die bottom. Then…

FOUR: Center the seater stem. Just like with the decapping stem, there’s thread play in the seating stem. Move the stem more toward an aligned center by simply securing its lock nut when there’s a bullet bearing up against the seating plug. As said, select a case with consistent neck walls to get best results. Now. The only foible with this is when you change seating depths by threading the stem up or down. It’s easy enough to repeat this op-step, but remember to do it. The BEST defense against alignment issues is purchase and use of a “competition”- or “benchrest”-style seating die. I’m talking about those having a spring-loaded sleeve that accepts the case fully before being run up to engage the seating plug. But, those still need to have their seating plug centered following the same sort of process used in these other “tricks”: snug the lock over a little pressure. That only has to be done once, though, for this die type.

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

Reloaders Corner: Case Trimming: finishing the job

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So you have a sack full of trimmed cases. Now what? Here’s what! A few tips on final preparation that may even promote better accuracy. Keep reading…


Glen Zediker


The most basic and necessary tool or tools we’ll need to get the freshly-trimmed case into shape to take on a new bullet is an “outside” and “inside” chamerfing appliance. These are most popularly housed in one hand-held tool: one end does the outside and the other does the inside. Of course (of course) there are options, and some are right dandy.

LE Wilson chamfer tool
Here’s a basic and common LE Wilson inside/outside chamfering too. One end does the outside, the other does the inside. Shown is a 45-degree tool.

After trimming the case mouths will be square, flat, and appear wider-walled than before. That’s normal.

There will usually be a little edge-ring of brass on the exterior surface of the case neck, and that’s the reason for the wider appearance. That’s easily remedied. It takes only a light skiff using the “outside” function of the tool.

trimming burr
That little ring of brass around the top outside edge of the case neck: just get it gone. Doesn’t require a cut, just a skiff with an outside deburring tool.

Don’t cut into the outside, just remove the ring. No bevel is necessary; that only thins the case mouth. If the ring is left standing, the case might not want to feed, and then there will be little shards of brass here and there.

Next, the inside. The inside edge of the case mouth needs to be broken and also beveled to more easily accept a bullet. Now we’ve got options in depth of the bevel and angle of the bevel.

The long-time “standard” is a 45-degree chamfer. That functions okay to allow most bullets to sit unsupported in the case neck prior to seating. I believe, and I’m not nearly alone, that a steeper angle is better. For anyone loading bullets that are of a longer, “spikier” form, I strongly recommend something closer to 30 degrees, or less. These are often called “VLD” cutters or chamfer tools, and that is because these tools followed the “low-drag” style bullets that, among other attributes, featured relatively longer, more steeply angled boat-tails. They also have relatively thinner jackets (“J4”). Essentially, a 45-degree pathway and the geometry on the bullet didn’t mate up.

Lyman VLD chamfer tool
Here’s a Lyman “VLD” chamfer tool. It’s got a 22-degree angle. I’ve used other brands that were 19 and 20, and I honestly don’t know that a couple degrees makes much difference. However! There’s a world of difference between this and a 45-degree tool.

The result of a greater angle mismatch is that the bullet gets a pretty hard start into the case neck, and it can also get a crooked start, and that’s because it’s not sitting “into” the neck very far. It’s in a precarious position and easily tilted. These long bullets create what amounts to more leverage in less-than-perfect case necks, which is going to be the most of our case necks unless we’re neck turning. (It’s also why I’m a big believer in a bullet-seating stem that engages farther down the bullet nosecone; this also helps reduce the angular deflection in seating.) I’ve seated and then pulled bullets from cases with 45- and 20-degree chamfers, for instance, and those from the shallower angle show noticeably less scuffing. (Plus, many of the custom-made low-drags feature a “pressure ring,” which is a tiny elevated ring right at the boat-tail/shank junction, usually about 0.0005 diameter, which helps obturation. That ring can get deformed by a 45-degree chamfer.)

It’s not the depth into the case neck cylinder that improves the transition into the case neck, so a “bigger” cut with a 45 won’t do a thing. A steeper cutter is going to make a deeper extension into the case neck simply because the angle is steeper.

Cutting the inside, do not go for a knife edge! For a yardstick, I suggest going about halfway on a 45-degree cut and 2/3 on a VLD-style chamfer tool. By that I mean that the appearance of the wall thickness at the case mouth is roughly half after chamfering that it was before.

Forster 3-way trimming head
There are also “all-in-one” cutter/chamfer/deburr heads for some case trimmers. These are one bugger to set up, but they work well and save a ton of time and extra steps, and since it’s incorporated into the length-trimming operation, the chamfer consistency will be spot-on. Trick is finding one that cuts a shallower angle on the inside… If not, it’s going to produce better results overall to do this operation separately.

It is important, at least in logical thought, to have the same chamfer depth on each case to ensure perfectly consistent engagement with the bullet shank. Honestly, I don’t know if that shows up on a target, but it’s easily attained using either an LE Wilson or Forster case trimming base, as well as some others, with the addition of a chamfering tool in the apparatus to replace the length trim cutter. It’s an extra step in retooling and adjustment, but then if the cases are all the same length and the stops are set, each case mouth will have an identical chamfer.

LE Wilson neck reamer
Here’s a trick and half for seating flat-base bullets. These are difficult to get started straight since there’s no boat-tail to ease transition into the case neck. I use an LE Wilson inside neck reamer set to engage a feature built into that tool. LE Wilson added a short tapered area that can be run into a sized case neck, about 1/16 inch, that machines something close to a “shelf” that provides a nest for the flat bullet base. There’s a noticeable improvement in runout on the flat-base bullets I have seated with and without this cut. [Note: This is the “standard” inside neck reamer intended to remove excessive thickness in the case neck cylinder on fired cases, not sized cases; the feature just described is an accessory benefit and, again, is engineered for use on sized case necks.]

The preceding is a specially-adapted excerpt from Glen Zediker’s newest book Top-Grade Ammo. Available right’chere at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, as well as others.

RELOADERS CORNER: Case Trimming Tools

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Choosing the right case trimmer has to do with the quest for precision, the need for speed, and the budget bottom line… Here’s how to make the fewest compromises.


Glen Zediker


Last time we talked about the needs and reasons for trimming bottleneck rifle cartridges. It’s a necessary step in the case preparation process, at least at some point or three before the brass hits the trash can bottom.

MANUAL
Case trimmers are available from most all industry tooling manufacturers. Most replicate a miniature lathe: the case is held in place at its back end, usually by a collet-type appliance, and suspended from its front end via a pilot, surrounded by a cutting head, that fits inside the case neck. They have a crank-handle.

case trimmer pilot
Here’s the source of imprecision in most trimmers. The case is held securely only at its base. The cutter pilot has to be smaller than the case neck, and can’t have a close fit. There’s a lot of wiggle room and that translates to non-square case mouths and even length inconsistencies.

This essential architectural arrangement carries potential contributors to imprecision. The case body is not supported, only the case head is held firmly in place. The pilot goes in the case neck and, so it can go into the case neck, has some gap. Inconsistencies in case neck wall thickness and the inevitable case body warpage, plus plain old flex, can result in what some, me included, might call wobble.

If the case isn’t being rotated along a flat axis, then the cutter isn’t going to engage the case mouth squarely.

I think a better arrangement is taking the case head out of the equation and focusing on supporting the case body. To this end, I’m not bashful about saying something good about something I use, especially not when post-recommendation feedback continues to thank me profusely. Put it this way: if you asked me face-to-face which bench-top case trimmer to get, I’d say “LE Wilson.” Just like that. Check it out at Midsouth Shooters Supply HERE.

LE Wilson Case Trimmer
Here’s an LE Wilson. I bought my first one in 1985 and I’m still using it (just needs a new cutter head every so often). This tool produces square, precisely trimmed cases, and it does so quickly. This one shown is the latest-greatest version. The addition of the micrometer makes it the zoot-capri benchtop trimmer. That’s a real asset to precision for some operations, like case mouth chamfering, that you can use your LE Wilson for. Recommended.
LE Wilson Trimmer
The cases tap in and then tap out. There’s enough taper in the sleeve to secure the case against movement. It’s way on faster than locking and unlocking a collet. Plus, one LE Wilson base serves for virtually all cartridges, just change the sleeves.

I like this design because it uses a sleeve that holds the case and sits atop rails on the trimmer base. The case can’t move, and it doesn’t move. The cutter, which is the only thing that moves, engages the case mouth. All the alignment is in the parts of the trimmer itself; the case is taken completely out of the equation.

Forster Trimmer accessories
Another trimmer I like, and I do use, is the Forster. It’s what I recommend for those who want to get more of a “multi-purpose tool” out of their base unit. There’s a wide ranging array of add-ons, or add-ins, that make it serve to work over primer pockets, turn case necks, ream case necks, and even hollow-point bullets. I’m not exactly sure why, but my Forster does a superior job compared to others I’ve tried built along the same lines. The Brown & Sharpe collet is touted as providing higher precision than others out there.
case trimming accessories
There are a myriad of accessory add-ins for a Forster trimmer: shown is a neck reamer, outside case neck turning parts, centering pilot for primer pocket tools, primer pocket cleaner, crimp remover, power-drill adaptor, and the list goes on beyond these. Versatile!

POWER
Yeah boy. If you’re up for it, a truly specialty power case trimmer is the bomb.com. I really don’t think that adding power to a “lathe-type” trimmer is all that impressive or worthwhile. It helps ease the effort but it’s not necessarily speeding up the process.

There are two power trimmers that are more than impressive. One is a Gracey Match-Prep and the other is the Giraud. Both are expensive ($300+) but after processing a sack full of Lake City Match brass in a scant few minutes, the cost might get forgotten. Might. It really depends on the volume you do. I can tell you that, much to the contrary using a conventional tool, case trimming is the single fastest step in my case prep routine using a Gracey. I have not used a Giraud but have it on very good advice that it’s as good as all.

Gracey trimmer
Here’s a Gracey. It’s a powerful machine that’s a tad-amount intimidating the first time you use one. But just push the case in and bring it out. That’s it. It’s extremely fast and, according to my notebook entries, produces perfectly precise lengths as long as all the cases are full-length resized (the case stops on its shoulder in the holder). (Shown separately.)

Both work pretty much like giant overly-powerful electric pencil sharpeners. Push the case in and the spinning cutting head zips it flat in a heartbeat. Case length is determined by cartridge case headspace, which is to say that the case stops within the trimmer holder on the case shoulder. Clearly: trim only full-length sized cases to get consistent lengths. If the case shoulders haven’t been set back or at least all set the same, lengths will vary.

Take a look-see: Gracey, Giraud

Gracey holders work off the case shoulder, so all the shoulders have to be the same for best accuracy.
Gracey holders work off the case shoulder, so all the shoulders have to be the same for best accuracy.

Click here to see all the Midsouth Shooters Supply case trimming options.


Next time we’ll look at tools used to treat the trimmed case necks and finish this task in fine style.


The preceding is a specially-adapted excerpt from Glen Zediker’s newest book Top-Grade Ammo. Available right’chere at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, as well as others.