Category Archives: Reloading Corner

RELOADERS CORNER: Understanding Ballistic Coefficient

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Math and myth both get involved in bullet Ballistic Coefficient discussions. Keep reading to separate the two and learn exactly what BC is, and what it isn’t. MORE

bc

Glen Zediker

Years ago I explained in great detail to a fellow here all about ballistic coefficient and how it was calculated and how it could be used and how it can change and so on, and he stopped me: “So you mean it’ll hit furtherer on up the hill…” That’s it.

A “ballistic coefficient,” or “BC,” is a number assigned to a bullet that suggests its aerodynamic performance.

That’s a key word, “suggests.” The main suggestion is how well this bullet will fly compared to that bullet, and the one with the higher BC ought to fly better. Fly better means less drop and drift, and those, factually, are a product of the higher-number BC. My best all-inclusive definition what a higher BC does for us: less speed lost over distance. Regardless of the muzzle velocity or the distance, one bullet with a higher BC will lose relatively less velocity over the same distance.

bullet blueprint
Here’s a blueprint. All the information needed to calculate a BC is contained here. It doesn’t have to be a real bullet because a BC model is not a real bullet either. Design factors that influence BC are virtually every design factor: length, ogive, boat-tail, meplat, weight. These factors, in this instance, calculate to a G1 BC of 0.560. By the way, there’s about a 5 point BC increase for each added 1 grain of bullet weight.

BC is calculated based on a standard bullet model. There are 7 of those. Two are normally used to determine BC for conventional rifle bullets, like what the most of us reading this use. Ballisticians and designers know which model to apply to different bullet types. The common model is a “G1” (another is G7, which is becoming the popular standard for boat-tail bullets; G1 is based on a flat-base). The flight of this G1 bullet has been calculated at varying velocities and distances. It’s “all math” because a G1 does not in fact exist. BCs are derived by comparison.

g1
The older standard for most rifle bullets was the G1. The newer, and better, standard is the G7. However! BC is never chiseled into stone regardless of the model. It’s a way to compare bullets, and a place to start figuring yours out.

g1 and g7

The standard bullet of any form-factor has a BC of 1.000. An actual bullet that’s compared to the model at points downrange will either be flying faster or slower than the model. If it’s moving faster, its BC will be greater than 1.000. If it’s going slower, it will be less than 1.000. It’s a percentage of the standard or model bullet’s performance.

Now. That is also all that it is!

BC is not an infallible factual statement about precisely what a bullet will be doing when it’s loaded and fired at that target than moment with that rifle. Not nearly, not hardly.

To me, BC gives us a place to start estimating drop (elevation) and also clues to how much it will get moved by a wind. It’s a way to compare bullets.

BC changes! Day to day, place to place, hour to hour.

Some bullet makers publish a BC for a bullet based on actual testing (chronographs) but now it’s pretty much “just math.” That’s fine. Which — math or measure — provides the best information? Some believe that a measured, tested BC is more realistic and, therefore, more valuable. But, if the point is to compare bullets, calculated BCs is more reliably accurate.

We (NRA High Power Rifle shooters) have gone to difficult and frustrating lengths to collect data to calculate “real” BCs (chronographing at 500+ yards hain’t always easy). Measured BCs are quite often lower, and they are quite often higher. Reasons follow.

The accuracy of drift and drop tables clearly revolves around what the actual, at that moment, BC performance is from the bullet you’re shooting (compared to what it’s “supposed” to be).

Anything that can influence bullet flight influences the actual, demonstrated BC performance.

BC uniformity is important. Bullets that show uniform BC performance produce less elevation dispersion. A source for variation is the meplat (bullet tip). Hollowpoint match bullets are notorious for inconsistency in this area. There’s a tool, a “meplat uniformer,” that fixes it. That’s pretty much the point to the plastic points on bullets like Hornady’s A-Max line.

Atmospherics, which add up as a list of factors, have a huge influence on BC performance. Air density is probably the most powerful influence. Any conditions that allow for easier passage of a bullet through the air don’t detract as much from its stated BC as do any conditions that serve to disrupt its headway. BCs are based on sea-level so can easily show as a higher number at a higher elevation. I can tell you that bullets fired at The Whittington Center in New Mexico have a noticeably better BC than those shot at Port Clinton, Ohio.

Range reality is that the demonstrated BC changes from morning to afternoon and day to day and place to place. The calculated BC is not changing, of course, but the mistake is assuming that a BC is a finite measure of bullet performance.

Bullet stability is even a factor. For a stated BC to be shown on a shot, the bullet has to be “asleep.” If it’s not stable, it’s encountering disruptions that will slow it down. The rotational speed of a bullet in a test can influence BC. We’ve seen differences comparing different twist-rate barrels, and the faster twists often show a little lower tested BC.

Factors that don’t matter in BC? Caliber. I’ve been argued at often over this next, but it is perfectly and absolutely true: BCs work the same regardless of caliber or bullet weight. Two bullets that each have a 0.550 BC, for instance, behave the same. That’s helpful, and at one time was more helpful than it is now. When we had to use paper tables to get drift and drop data and there was a new bullet that didn’t yet have those tables done, all you had to do was find data for another bullet with the same BC, go to the same muzzle velocity, and that data was 100-percent accurate. A .308 and .224 that both have the same BC share the same table. Remember, it’s not “real,” it’s a mathematical model.

So if you take a load to the target one day and you’re putting on more elevation than the BC-based calculation says you should, the BC isn’t wrong. The day is just different.

Finally, does it matter (really) if a bullet BC is based on a G1 or G7 model? Debates continue. But, not really, and I say that because BC is still only a suggestion. G7 is a more closely matched model to what we’re usually shooting when we think of a “high-BC” bullet, but all the same factors day to day also influence its accuracy. Given access to the data, I definitely, though, go with G7 calculations to have a place to start from. My experience has been that there is less difference in varying conditions, but, again, it’s still (plenty) enough change that you cannot dial it in and win anything…

The preceding is a specially-adapted excerpt from Glen’s book Handloading For Competition. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

RELOADERS CORNER: 4 Bullet Seating Tips

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It’s the “last thing” that happens in handloading, and here’s a few ways to make it better. READ MORE

bullet seating

Glen Zediker

Last time the topic was bullet seating, but with a focus on safety — respecting the overall cartridge length that touches the lands or rifling in a barrel — and specifically making sure your bullet isn’t touching the lands (unless that’s what you want). This time here are a few ideas on how to improve the quality and consistency of bullet seating, and mostly from a tooling perspective.

A few things matter. The ultimate goodness is a round capped by a bullet that’s straight and undamaged, ready to get launched straight into the bore and then straight on to target center.

1. Die Design
I have long and often said that the single-most important tooling upgrade to improve the accuracy of handloaded ammunition is a better seating die. “Better” is better designed, and better designed, in my mind, is one that follows the “in-line” architecture.

LE wilson bullet seater
Here’s an LE Wilson die. There’s none more precise, but there are many faster to use! The sleeve-style seaters provide a close duplication in performance and results.

One of the first that comes to mind is the LE Wilson seater (there are others similar, but it’s the most well known). This seater style is the staple of Benchrest competitors. It’s not practicable for the most of us because it’s slow and a little tedious. How it works is that there is a seating stem that’s a very close fit to the die body. The die body and stem are concentric thanks to precision machining. The die body goes over the case, which has had a bullet placed in its neck, and the die holds the case in stable alignment. The stem is pushed down, seating the bullet. There’s zero “wiggle room.”

The difference in effect between that and a “standard” seating die, which has a stem threaded into a 7/8-14 press-mounted die body, is that the case isn’t free to move. In a conventional thread-in design, there’s a lot of room for movement in the case as it’s being run up into this type die. There’s slack in the case-shellholder fit, and slack in the fit of the case inside the die body. When the bullet that’s perched in the case mouth contacts the seating stem there’s a good chance it can get tilted askew. That then means there’s a good chance the bullet won’t be seated dead straight.

redding seating die
Here’s a Redding Competition Seating Die. The case is supported fully within a spring-loaded sleeve prior to accepting the bullet. Better!

Redding and Forster both make a press-mounted die that effectively duplicates the in-line Wilson concept. These both have a spring-loaded sleeve that tightly fits the case body. The idea is that the case fully enters this sleeve and is therefore fully supported against movement before the press handle stroke elevates the ram enough for the bullet to engage the seating stem. Much better!

2. Stem Check
Make sure that the tip of the bullet you’re using doesn’t contact the inside of the seating stem! This isn’t as common to see now as it once was. Longer, higher-BC type bullet profiles are prevalent enough that most manufacturers have increased the room inside the stem.

bad seating die stem
Not as common now as it used to be, but here’s what you don’t want! The bullet tip should not contact inside the seating stem.

Certainly, if the tip is bottoming out inside the stem, a few bad things can happen. One is that it’s easily free to tilt the bullet. Two is that the seating depth is then influenced by the tip-to-tip inconsistencies that do exist. Three is that the tip might get damaged in the process. This, by the way, is not nearly exclusively a concern to users of “spikey” bullets. I’ve been running into tip contact created by bullets with more blunt/rounded nosecones, like some of the lighter-weight .308 caliber bullets we’re using in .300 Blackout.

forster custom seating stem
If you’re a Forster user, they can supply a custom-dimensioned stem. I’ve been using these a while now and think it’s a great idea.

There’s more, though. A seating stem that contacts a bullet farther down its nosecone provides more stability during seating. It’s a greater surface area and that is another hedge against the potential for unwanted tilting.

seating stems compared
Contact area is better lower than higher. Here’s a standard stem next to a custom stem.

If you’re a Forster user, they have a custom seating stem option I have been increasingly using. Send a bullet and they’ll custom-made a polished stem that exactly fits it, and in the right place.

3. Start it Right
Can bullets be damaged in seating? Yes. Absolutely. Especially some of the thinner-jacketed bullets can get scuffed during seating, and the stem can leave a ring indentation on the ogive. Some swear that the ring indentation is not hurting accuracy; I say, “I don’t know, but it can’t help.” A stem that’s a little larger inside diameter, that’s also been smoothed to a gentle radius, will make the ring disappear. A good local machinist can help.

Lyman VLD chamfer tool
A more relaxed angle on the inside case neck chamfer eases bullet entry and reduces potential for jacket damage, and is also an asset to getting the bullet started in-line. This is a Lyman VLD tool.

One simple thing that results in a marked decrease in jacket damage is to put a more relaxed inside chamfer on the case mouth. Switching from a 45-degree cutter to one with a 20-degree, for instance, tool angle results in a deeper, smoother chamfer. This also overall reduces entry and seating effort.

Be nice to the bullet!

4. Case Neck Attention
This is related to every other point made so far. The more consistent case neck walls are, the ultimate result is a better centered case mouth, and that results in less chance that seating the bullet is going to try to move the case neck, and also less chance there will be unequal contact as the bullet enters the case neck (less abrasion).

Better concentricity, as said, means the bullet can start straight into the neck and then all the precision alignment built into the tools gets to show its merit.

This is where brass segregation (for wall thickness consistency or runout), outside case neck turning to improve wall thickness consistency, and initial choice on the brand of brass all come in.

Much of that also comes from the choice of sizing die and how well it’s been set up, and that’s been talked on in these pages before (and will be again, no doubt).

And, making sure the case neck cylinders are all the same heights makes a difference too, because that means each bullet is encased in an equal amount of material.

Check out dies at MSSS HERE
Find a chamfer tool HERE
Learn more about custom stems HERE 

The preceding is a specially-adapted excerpt from Glen’s book Top-Grade Ammo. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

RELOADERS CORNER: Seating Depth Issues

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Don’t take anything for granted! Safety and suitability are both at risk if you don’t take time to analyze and act on this important topic. READ MORE

land illustration

Glen Zediker

As said often, it’s sometimes recent experience that leads to my Reloaders Corner topics. Whether it’s a question I’ve been asked, usually, or, in this case, a malfunction I’ve had, those things are fresh in my mind. I hope to believe, and have to believe, that any such topics aren’t only a question for them, or for me.

That brings us to bullet seating depths, which really means overall cartridge length, using some particular bullet.

Usually, when we’re loading for a rifle with a box magazine, either bolt-action or semi-auto, the cartridge overall length — that’s measured from the base of the case to the tip of the bullet — defines and determines the maximum length. Usually.

What ultimately determines the cartridge overall length maximum, though, is really the first point of contact that the bullet makes (will make) with the rifling or lands ahead of the chamber throat. That space, and therefore overall round length, has a whopping lot to do with the chamber reamer specs, and also the reamer operator’s judgment in some cases, but we need to know.

It also can have a whopping lot to do with the bullet! And that’s what the most of this next is all about.

So here’s the lesson to learn, and, for me, to relearn: Do not assume that if the round fits into the magazine it will be fine. I will, at the least, freely admit to my mistakes because, one, I dang sho should know better, and, two, if I know better and still don’t do better confession is my punishment. Well, not really, but it’s always a wake-up call.

Different bullets have different profiles, different ogive architectures. The ogive is the “curve” beyond the last point up the bullet that’s caliber diameter (meaning full diameter) ending at the bullet tip. My slang but descriptive term for this is “nosecone.” Tracing up this curve, some point will be equal to land diameter. So where this point is on the seated bullet and where this point is ahead of it in the chamber matters a lot.

Unless it’s done as a deliberate tactic, there needs to be some space, some distance between the land diameter point on the bullet nosecone and the lands. The amount of that distance is referred to as “jump,” because that’s descriptive. It’s the gap the bullet has to cross through to engage into the rifling. Usually the closer the better, and that “tactic” used often by precision shooters (mostly long-range and Benchrest competitors) is to purposely seat the bullet so it’s touching the lands. That’s done in the belief that if there’s no jump, then there’s no ill effects from jump. It’s very often right, and I’ve proven that to myself many a time. It’s not always right, but then if it was this all would be too easy.

The reason there needs to be some space is because when a bullet goes from just off to just on the lands, pressure jumps. It’s a “spike,” not a surge, but it’s enough to put a load that’s nearing the edge over the edge. In something like a .223 Rem. it’s about a half-grain-worth of propellant.

hornady 52
Here’s one I messed up with. The ogive or nosecone profile on this bullet is much “higher” than normal for a match bullet of this weight and it encountered the lands at a much shorter overall length than any others I had used. I learned the hard way, even though I already knew better.

So. Here’s the lesson I learned again, but this one wasn’t my fault! Honest! Several years ago, however, here’s one that was my fault: new (to me) match bullet, a short 52-gr. I wanted to try for reduced-course NRA High Power Rifle events. Rifle had a Wylde .223 Rem. chamber. A Wylde has a throat length between a 5.56 NATO and a SAAMI-spec. .223 Rem. That means the throat is fairly much more generous than commercial .223 Rem. specs. The maximum cartridge overall length in an AR15 box magazine is 2.260 inches, and I go 2.255 for a margin. I checked some industry manual data for this bullet and did notice that the overall cartridge length listed in the data spec table was a good deal shorter than that. I quickly did some “math” but without numbers (so it wasn’t really math) and decided that since I had a longer chamber I’d ignore that and just seat the bullets to 2.255. Blew primers right and left.

Back home and gage in hand and, dang, they weren’t kidding! I was about 0.020 into the lands at that cartridge length. That’s a honking lot. That’s also ultimately dangerous because of the free-floating firing pin tapping off the primer when a round is loaded into an AR15. A bullet that’s getting jammed into the lands is greatly more resistant to chambering freely and fully.

I humbly learned my lesson.

Get a gage and use it! The best out there is the Hornady LNL Overall Length gage. This tool lets you very easily find the overall round length that touches the lands with your bullet in your barrel. Very valuable, that.

lnl oal gages
A Hornady LNL OAL Gage will show right quick like and in a hurry with the seating depth that touches the lands is with your bullet in your gun. Valuable!

Use it in conjunction with its companion “bullet length comparator” insert for the very best precision. That tool measures a bullet at a point on its ogive that (usually) corresponds closely with land diameter. It won’t be perfectly the same, but it doesn’t have to be. What matters is that it gives a more accurate figure. Avoiding the bullet tip in a measurement eliminates that (guaranteed, by the way) inconsistency in accurate measurement because of bullet tip variations.

LNL comparator
A “comparator,” like this one from Hornady’s LNL line, is a much more accurate way to measure seating depth because the bullet tip doesn’t get involved. I like the curved one: easier and more accurate by my experience.

Now. To the recent experience: It was with a .300 Blackout (AAC) subsonic. I did not have the means to gauge this using my tools (then, but I do now). However, that wouldn’t have mattered in this case, and why is next.

Tested a factory load. Liked it. Noticed nothing unusual. Functioned perfectly, shot well. Brought it home and filled a magazine, loaded one in the chamber, and set it aside. Folks, just so you don’t think I’m irresponsible, that gun is what I keep at the ready for home-defense. So, my son, who had gone in to unload and then dry-fire the gun, came up and said, “Dad. The bolt won’t open.” Dang. It wouldn’t. I started thinking up all reasons that might be behind that. The bolt carrier would retract a little way, which was the limit of usual “play” in the bolt travel inside it, so I didn’t think anything was broken. To remove the round I pulled off the upper, took it to the shop, and pried back the bolt carrier from the underside. A couple of careful but firm enough strokes and it opened.

The bullet had really jammed into the lands! I mean really jammed. Extracting the round and looking at it, land impressions were clear, and measuring the extracted round showed it was 0.022 longer than the new, un-chambered round. Unseating the jammed round pulled the bullet that far out from the case neck.

I manually inserted another round of the same into the chamber and gave it a nudge-in with my finger, and, sure enough, there it sat not nearly fully into the chamber. Had to tap it back out.

jammed bullet
Here’s the “stuck” round, right, talked over in the article. Land impression is pretty clear, and pretty deep. Notice also that the bullet got pulled out a might upon finally opening the action. On left is the same round out of the same box that was pushed into the chamber; land marks also, just a lot lower!

So. Since it’s a factory load, I really couldn’t have had a clue that it wasn’t compatible with my chamber throat. But now I do. And, for a clue, do that same yourself. If the round won’t drop in and out of a chamber fully and easily, that might be a problem. I still don’t know what the actual measured amount of the excessive length might have been. To find that I’d have to get a box of those bullets and gauge them using the LNL tools. I’m not going to do that. I’ve chosen another load that’s no-issues.

I say “might be” because, again these rounds functioned well, but, also, well, that can’t be good…

I suppose I will now need to start handloading for that contraption. I have also written down 100 times: “I will always check the chamber throat, even if it’s not a long-range rifle…”

Find gages at Midsouth HERE and HERE

The preceding is a specially-adapted excerpt from Glen’s book Top-Grade Ammo. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

RELOADERS CORNER: Case Trimmers

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An ideal case trimmer provides precision, speed, and affordability. Here are some ideas on avoiding compromise. READ MORE

Hornady Cam-Lok
Hornady Cam-Lock. Good trimmer at a fair price. See it HERE

Glen Zediker

At some point, or points, cases need to be trimmed to a shorter length. Brass flows. Therefore, a case trimmer is pretty much a given in the tool assortment for any handloader.

There are needs and wants, realities and ideals. That’s true with many things, and applies often to reloading equipment. Ideally, a case trimmer will go beyond just trimming the case to a shorter length. They all do that well enough. I think it’s important that a case has a square mouth — dead flat across the top. This is an asset to getting a bullet started well into the case neck during the seating operation.

A Good Trimmer
There are a variety of trimmers available from most of the popular industry tooling suppliers. And most follow a pretty similar form and formula: a little hand-cranked lathe. In these, the back end of the case is chucked into a collet-type fitting. A caliber-size pilot that’s centered in and surrounded by a cutting head goes into the case neck and supports the front of the case.

Not nearly perfect! There are a few reasons and sources for reduced precision. The tool alignment may be true at each “end” of the trimmer, but the case we’re working with probably isn’t true. Mostly, since there has to be a gap for the pilot to freely rotate, and since case neck walls aren’t all consistent in thickness, the fit isn’t close enough to prevent out-of-round rotation. Along with the inevitable case body warp there’s bound to be a tad amount of wiggle. Since the case is supported only at its head area, not by its body, there’s flex afoot.

None of that means the case neck won’t get trimmed to a shorter length, which is the general idea. It does, however, mean that it’s not liable to be perfectly squared up.

LE Wilson
LE Wilson. See it HERE at Midsouth.

A Better Trimmer
I rarely just overtly recommend one tool over all the others, but after a good many years working with case trimmers, I can and will tell you that the LE Wilson design is the best I’ve yet tried. I guess, yes, that is just opinion, but it’s really not.

The difference in this trimmer design is that the case is supported within a sleeve by its body. There’s no polarized suspension front and back. Mostly, there’s no pilot. The cutter on an LE Wilson faces off the front of the case squarely. The sleeve holding the case sit atop a pair of rails and the whole arrangement excludes case condition from the process.

le wilson sleeve
Tap it in… Then tap it out…

le wilson sleeve

So why doesn’t everyone use one? Honestly, I’m not entirely sure. It is a different arrangement, and it’s not cheap, especially not if you accessorize the fool out of it with a stand, a clamping device, and a micrometer. It’s not more than the other higher-end manual trimmers though.

It’s also fast! There’s no clamp-twisting to get the next case in place, and back out again. The sleeves are slightly tapered inside so the case is tapped in and then tapped out. With a little experience it’s amazingly quick to get through your block full of brass.

Flexibility
Virtually all case trimmers can provide additional utility, do different jobs. The cutter can be replaced with a reamer, and some can get reworked into outside case neck turners.

My choice is usually a stand-alone station, and that’s mostly because it’s pretty tedious refitting the appliances. I am, or at least have become, lazy.

forster case trimmer
Forster. This is a good choice especially for those who want to make a multi-purpose tool out of their base unit. There’s a big collection of add-ons that let work over primer pockets, turn case necks, ream case necks, and even hollow-point bullets. Its precision is better than most.
forster accessories
A a few of the things that can go on a Forster. Very versatile tool!

As with all said about alignment for case length trimming, that is also all the same for using a trimmer for other chores. And, yes, I still think the LE Wilson works best as a reamer, for instance, and that is because all the alignment precision is built into the tool itself; the case doesn’t play a role.

About options, by all means fit up a “combo-head” if it’s available that will finish the trim with a nice inside/outside chamfer/deburr. Big time saver. These can be a trick to get set just right, but it sure saves time.

Power
It sure is nice to get a break from the crank! There are, though, as I see it, two kinds of power case trimmers. Those that replace the hand crank with an electric motor and those that are designed from the start to be powered.

Some trimmers offer a means to add your own power source, like an electric screwdriver or drill.

Gracey Match Prep
Gracey Match Prep. Pretty much a big motor! It’s intimidating on first use, but just push the case in and it gets trimmed (and chamfered). It’s way quick in use and produces precise results.

My favorite proprietary power trimmer is a Gracey “Match Prep.” Designed by the late Doyle Gracey as a fast and easy way to trim huge quantities of Lake City brass for NRA High Power Rilfe shooters, it’s a serious machine. It works like a gigantic electric pencil sharpener, at least in spirit. Pick up a case and push it forward into a collar and it’s trimmed and squarely faced. No clamps or sleeves. The case shoulder stops against the inside of the collar, so it’s imperative that all cases are resized prior to use. As said last time, though, that’s really the only time you’ll get consistent results with any trimmer.

gracey holder
A key to a Gracey’s speed is that the cases stop on the case shoulder: just push it it!

I don’t know how many cases I can trim in an hour because I’ve never spent an hour using a Gracey. I can easily do 100 in under 5 minutes.

Another very good power trimmer is the Giraud. Its essential means for and in operation are about the same as Gracey but it is a nicer package with more features. Gracey is pretty daggone simple. That’s not all bad. I’d say Giraud is the best, and its price does reflect that.

One Last
Again, it’s important to evaluate the overall condition of a batch of cases, related to how many uses they’ve had. Having grown a little longer isn’t likely to be the only thing that’s changed in a case that exceeds whatever limit you set for it.

And, speaking of, the “trim-to” length is usually 0.010 inches shorter than the maximum SAAMI-stated overall case dimension.

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

Check out some more options at Midsouth HERE

Gracey
Giraud

The preceding is a specially-adapted excerpt from Glen’s book Top-Grade Ammo. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

RELOADERS CORNER: Case Trimming

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We all have to trim bottleneck cases sometime. Question is when and how much, and then “how,” and here’s a place to start. KEEP READING

case trimmer

Glen Zediker

After going through that last series on keeping up with changes in cases resulting from their use and reuse, “flow” was a culprit behind the majority of detrimental changes. That is: Brass flows during firing. It moves from where it was to somewhere else. Since there’s a finite amount of material in a case, one place is getting thinner and another is getting thicker. The sources of the material, where the flow starts and where it stops, are primarily case necks and case heads.

To completely finish up on all this, the most obvious indication that there’s flow is measuring case lengths from base to mouth.

case trimming
The primary reason to trim is to keep overly-long cases from overrunning their space in the chamber. If the case mouth encounters the end of its allotted space, it can pinch in on the bullet, elevating pressure. Now, there’s usually a good deal of leeway before safety can be a question, but don’t push it…
measure case length
A caliper is the only tool needed to measure case length. It’s not really necessary to measure each and every case each and every time. It’s a whopping lot faster to set the trimmer so it just touches the shortest case you have (revealed through the process itself in setting up the trimmer) and trim all the cases using that setting locked in place.

First, and very (very) important: The ONLY time to check case length, or to trim cases, is after they have been sized! A fired, unsized case will be shorter than it was going in. The reason is because of the expansion in the case that resulted from firing. When the expanded areas are squeezed back to spec by a sizing die the case gets longer as it gets smaller in diameter, same as rolling a ball of modeling clay out on a table. After sizing is also the only time we can we know that the case shoulder area is consistent in dimension.

You’ll see two length figures published for your cartridge of choice: maximum length and trim-to length. Published trim-to length is usually 0.010-inches under what’s listed as maximum.

I got a gage umpteen years ago that could indicate the maximum case length a chamber could accommodate — technically, a “chamber length gage.” Man. I checked the chambers in my main rifles and found that they were all well more generous than the SAAMI-maximum. That didn’t really mean a lot, in fact, to how I proceeded. And it also didn’t mean I can advise ignoring the potential for danger in exceeding SAAMI-maximum. It just pointed out that there are differences in chambers, gun to gun, and at least showed me that not exceeding max stated length should easily keep you safe.

chamber length gage

If a case got too long, exceeded the amount of room given to it in the chamber, that would be a safety problem! The bolt may not close fully. And, if it did, the extra length would create a pinching-in constriction, and that would spike pressure.

We can easily imagine that there’s an influence from relatively longer or shorter case necks in their influence in consistently encasing the bullet. And I’m sure we’d be right. Trimming cases all the same should mean that all the case neck cylinders are the same height. Someone looking to maximize accuracy is liable to get worked up about that enough to trim each firing. I trimmed my tournament cases each use. And, no, none were remotely approaching maximum length. It’s reasonable to further suppose that more or less retention will influence velocity consistency.

Another performance asset may or may not happen, depending on the trimming tool chosen. But. A good trimmer will square the case mouth. I’ve seen a many new cases with a “half-moon” cut after trimming. A square case mouth helps a bullet start and finish straight when it’s seated.

case trimmer
Not all case trimmers are equal. We’ll talk more about some I like next time, and I’ll tell you why.

My routine for this sort of “accuracy-oriented” case trimming is simple — tedious, but simple. I don’t measure each case. I just run them all through a trimmer set to “some” length. Some are trimmed more or less, some just show a bright scuff on one little bit of the case mouth, but they are then all the same length. If I can’t prove it in group sizes, it sho does set my mind at ease that all the cases are holding all the bullets more nearly the same.

For those rifles that aren’t tournament guns, the only concern is that none, indeed, become too long. Those I will check at that “4-firings-in” point. Some may have reached SAAMI-maximum, most won’t have, but all will be longer than when started. I start them at a figure close to suggested “trim-to.” Stop and think about it, and if there’s been overall a 0.010-inch length increase, that’s significant.

As with all things associated with use and reuse in semi-autos compared to bolt-actions, cases are going to grow more and faster in a gas-gun.

Another instance where it’s important to keep up with case lengths, and that, again, really has to do with making them all the same, is for those who crimp (with a conventional cannelure method).

Now, there’s zero harm in using a longer “trim-to” length, and that may be more popular than my method. These lengths are stated in reloading manuals. Keeping up with it over years, I’ve seen no difference in the rate of lengthening trimming longer or shorter; I trim “shorter” solely as a matter of consistency over the (short) life of my semi-auto cases.

Next time more about the tools.

Get started shopping HERE

The preceding is a specially-adapted excerpt from Glen Zediker’s book Top-Grade Ammo.

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

Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE

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RELOADERS CORNER: 4 Firings In, Part Two

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Cartridge cases always fail on the “next firing.” Question is which one that might be. Need to know! KEEP READING

beat case
I apologize for the image quality, but these were taken a while ago. Fortunately, for me, I didn’t have anything on hand that shows even close to the beating this one took. Cracked neck, head crack. Rare to see one case with both of the most common failures. It was attacked by an M14.

Glen Zediker

I’d always rather say it all at once, but the realities of tolerance, and space, sometimes mean I have to split a bigger topic into smaller installments. The “tolerance” part is how many pages you all are willing to scroll through!

This multi-part topic is when, and then how, to check after the progress of changes commencing with the firing on a new case. It’s the “progress of degeneration,” in a way of looking at it because the concern is getting a handle on when enough change in the brass has come about to require attention. Or abandonment. As said then, for me that’s 4 firings. That, as said last time, is when I might see changes that need attention. Also as said, that figure didn’t come out of a hat, but from my own notes in running my competition NRA High Power Rifle loads.

The areas most affected are the case neck and case head area. Case neck walls get thicker, and that was the focus last time. Well, the case head area body walls get thinner. Primer pockets get shallower and larger diameter.

As started on: Brass flows during firing. It expands, then contracts, and when we resize the case, it contracts, then expands (a little). This expansion and contraction makes the alloy harder over the entire case, but with more effect in areas of more expansion, and flow. Replace “hard” with its effect, “brittle,” and that’s a clearer picture. This increasing hardness influences its reaction to being sized or otherwise stretched. As with many metals, bend it back and forth enough times and it will break. It will also fail if it loses enough resilience, or thickness, to withstand the pressures of firing.

Case Head
When a case is under pressure during firing, the brass, like water, flows where it can, where it’s more free to move. Of course, the chamber steel limits the amount it can expand. The case shoulder blows fully forward and the case base is slammed back against the bolt face. There is, therefore and in effect, a tug on both ends — it gets stretched. The shoulder area is relatively free to expand to conform to the chamber, but the other end, the case head area, is not. Since that’s the area of the case with the thickest walls, it doesn’t expand “out” much at all. What it does is stretch.

The “case head area,” as I refer to it here, is the portion of the case above the web, which is just above the taper that leads in to the extractor groove. The “area” extends approximately an eighth-inch up the case body.

case pressure ring
Here’s a “pressure ring.” You’ll see this after firing, if you see it. And, if you see it, that case is done. The bright ring indicates excessive stretching, which indicates excessive thinning.
head separation pic
Closer view of another sectioned case. This one here was fixin to pop. 

That portion of the case does not fully expand and grip the chamber, but the area immediately ahead of it does. So the case body expands and grips the chamber, and that last little bit back to the base can and does move. It stretches. If you see a ring circling the case, noticeable because it’s lighter color than the case body, and it’s in this area, I’d say that case is done. The ring will be evident after firing, not after; don’t confuse a shiny ring around the case in this area with what can be normal from sizing, especially if it’s been a hotter load. That is pretty much a scuff from the sizing die squeezing down this expanded area.

And that’s right where a “head separation” occurs. It can crack and also blow slap in two, and that’s the “separation” part of case head separation.

This is a spot to keep close watch on as cases age. It is also the area that is more “protected” by sizing with less case shoulder set-back. That is, pretty much, where the freedom for the stretching movement in this area comes from (the case shoulder creates a gap). However! As said many a time, semi-autos need some shoulder set back for function, and it’s the reason to use an accurate gage to determine the amount of set-back needed.

case head separation
Ultra-high-precision gage, made by me. Not really. It’s a selectively bent paper clip, and running this down inside the case and and then back up the case wall can signal a dip-in in the head area, which signals thinned walls. Feel it? Case is done.

Some folks unbend a paper clip and run it down inside a case and drag it up against the inside case wall as a sort of antenna to see if they detect a dip-in near the head area, which would indicate that the wall in this area has been stretched thinner. If there’s enough to feel it, that case is done.

Since I’m working off this “4 Firings In” checklist, if you’re seeing a sign that a head separation might be nigh in that few uses, chances are the shoulder set-back is excessive, and also too may be the load pressure level.

Primer Pocket
Another case-head-area and pressure-related check is the primer pocket. As said, the primer pocket will get larger in diameter and shallower in depth each firing. As with many such things, the questions are “when” and “how much,” and the main thing, “how much?”

If the pocket gets excessively shallow, and that’s judged by a primer that seats fully but isn’t at least a tick below flush with the case base, there could be function issues. There’s a risk of a “slam-fire” with a semi-auto that uses a floating firing pin, and, if there is actual protrusion, that has the same effect as insufficient headspace.

primer pocket uniformer
A primer pocket uniformer can reset the depth of a shallowed primer pocket to what it should be, but the real test for me is how easily the next primer seats into it. If it’s significantly less resistance, I’ll say that case is done.

Shallower can be refurbished. That’s a primary function of a primer pocket uniformer. Larger diameter, though, can’t be fixed. I’ve mentioned in another article or two that, any more at least, my main gauge of load pressure has become how much primer pocket expansion there’s been. I judge that without using the first gage, well, unless my primer seater is a gage. If a primer seats noticeably easier, that’s the clear clue that the pocket is too big. Another is seeing a dark ring around a fired primer, indicating a little gas leakage.

Measuring primer pockets is a waste of time, say my notes at least. First, it’s not easy to accurately (truly accurately) measure a pocket, especially its diameter, but, that’s not really what matters. It’s how much grip there is to maintain the primer in place during firing.

I pay close attention to resistance in primer seating and won’t reuse a case that’s too easy.

Good deal on what I think is good brass, especially if you’re an AR15 loader — HERE

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

Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE

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RELOADERS CORNER: 4 Firings In

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Along with all the other operations we do to them, cartridge cases also need maintenance. A good question is “when”? That’s next… KEEP READING

old case

Glen Zediker

I tend to write much of what I do for those who reload for production. Those are folks expecting good utility in exchange for the expense and effort: a reliably-performing round of ammunition, over and over again. They’re loading and reloading because they like to shoot. It’s a big bonus to most, and I include myself in this group most of the time, if that good performance comes with a minimum of effort. Clean, size, prime, fill, seat, shoot. Five steps to get to the one thing that matters most: shoot! I am also in another group some of the time, not as often now as I once was, and those folks may add a few more steps before getting to the “shoot” part (case prep mostly).

It would be wonderful if that simple cycle endured without end. But it won’t.

Overall case condition after X-many firings varies A LOT because of a lot of factors, variables. What matters is getting a handle on it. I look over each case each time I load it, but I don’t break out the measuring tools. That’s not neglect. There is never (ever) any excuse for neglect. That’s not what this is about. It’s about working out a responsible, reasonable, and realistic schedule for when to take a close look at the progress in condition that new batch of cartridges cases has followed after some time.

In my experience, which is what’s in my notes, I say that’s 4 firings.

I went through the per-use checks enough times to know the schedule one brand and lot of brass, used with the same loads in the same barrel, follows with respect to changes. And by that I mean when changes require attention. I’m also starting with prepped cases, including trimming, before their first firing.

Let me make clear that I’m not suggesting that 4 firings is maximum case life! What I am suggesting is that this is the point where it’s likely to see measurable influences from use and reuse, and, as such, that it can be measured. That’s what we’re after now: take a check to see what’s happening, and that also is a big help toward getting clues about where and when these changes might get noticeably influential.

So, to be clear: the case has been fired four times, reused three times. Next loading, if there will be one, will be for the fifth use.

chamber reamer
We, or more correctly, our cases, are at the mercy of this thing: a chamber reamer. It sets the amount of space the case can expand into.

Changes
Continuing to use and reuse cases, we’re not really using the same cases each time. The cases change, and much of the change comes from material flow, which is brass.

Here’s how it goes, which is to say here’s how it flows: Case neck walls get thicker. The case head area body walls get thinner, over a short span of the body. Primer pockets get shallower and larger diameter. Overall, the alloy hardens over the whole case.

As gone on about a few times in this spot, there’s going to be more change in cases run through a semi-auto than those used in a bolt-action. That’s because of the necessarily additional (comparatively speaking) sizing and also the additional stress resulting from the firing cycle. There’s more flow because the cases are free to expand more.

drop bullet
A simple, and important, test to check if case necks walls have thickened excessively is to take a fired case and drop a bullet in it. If it won’t drop without resistance, stop! That’s way too much.

The Neck
All case necks expand to whatever the chamber allows. There’s no relationship between that and sized dimension because, clearly, there has to be a small enough neck inside diameter to retain the bullet. It is, though, one of the reasons case necks tend to give up quickest (plus it’s the thinnest-walled area on a case).

The case neck is my primary concern, and the first thing I check. If the walls get too thick it’s possible to cut the space too close between the case neck and the case neck area in the rifle chamber. There might be interference upon bullet release, and that creates excessive pressure, or sure can. All that depends on what the chamber allows for expansion room.

The most simple check is to see if a bullet will freely drop into a fired case neck. If it won’t, stop! Do not reuse that case as-is. A case that won’t pass this no-tool test has excessively thickened.

Somewhere in your notes should be a figure indicating loaded outside case neck diameter, on new brass. This dimension is exclusive of the sized neck diameter, because when the bullet is seated the neck is going to expand to accommodate the bullet. Another check of loaded outside neck diameter will show if there’s been thickening. If an inside neck sizing appliance is used (a sizing button), then that will tell you also, comparing it to what you also recorded for the new case after sizing it. (And it’s a good reason to always run new brass through your sizing die, even if it’s “ready to go” out of the box.)

I hope it’s clear enough why it’s important to “write everything down.” References, standards are big helps.

Direct checks of the neck walls themselves using a suitable tool will show thickening. However! Case necks don’t necessarily thicken the same over the entire height of the case neck cylinder. Remember, the brass is flowing so moves in a direction, and that part of the case has a wave going forward, toward the muzzle. There can and likely will be a tapering from thicker to thinner. Measure at more than one point.

Safety is one thing, and the most important thing, and then the other thing is accuracy. Case neck “tension” needs to be consistent from loading to loading to get reliable accuracy.

Fixing it? An inside case neck reamer is the easiest and most direct means. However! Make double-dang sure you know the numbers and therefore how and at what point to use it! Many are intended for use on fired (not yet resized) necks. Others are a specific dimension that you may or may not be able to specify. Thinning the case neck walls using an outside case neck turner is another direct remedy. A little tedious.

forster reamer
The best way I know to remove material to refurbish overly-thickened case neck walls is an inside case neck reamer. This is a Forster, designed to work with their case trimming base. Trick is knowing the case condition it was designed to be used with. This one is dimensioned for use on fired, unsized case necks (it’s 0.003 under bullet diameter). Run it on a sized neck and way too much brass comes off. Various sizes are available.

Reamer or turner, though, this job hasn’t finished until the refurbished case has been run through your usual sizing die, and checked again for diameter.

Well, so much for this here and now. Out of room! More next time…

See REAMERS HERE

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

Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE

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RELOADERS CORNER: Choosing Your Brass

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It’s not all the same! Depending on needs and application, there are three decisions that can have an impact on your satisfaction. READ MORE

norma brass

Glen Zediker

Last time I offered a few ideas on loading the same cartridge for use in different rifles. Essential message in that was, in one word, “compromise.” There’s some give and take when we’re trying to please more than one at time, as such is life…

Choosing cartridge cases is a little, to a lot, the same. Different rifles, different action types, different uses, different budgets, all suggest input that helps determine what works best, all around.

There are three things to consider, maybe four.

One is the action type. Semi-autos need “tougher” brass. That, overall, means “harder,” not necessarily thicker. Due to the resizing requirements for good function, which means a little “more” in all areas, there’s likewise more expansion in each subsequent firing. Brass made of harder alloy is less, not more, susceptible to failures — by my experience. Considering the elastic and plastic properties of brass, harder exhibits a little less effect from each.

I prefer harder composition brass for a bolt-gun too. Most NRA High Power shooters do. Reason? It runs better! There’s less “stickiness” in running the bolt for rapid-fire events.

Two: case capacity. They are not nearly all the same! My experience has shown me that more capacity is better, and that’s especially if we’re wanting to edge toward max-pressure loads. Even though the pressure generated inside the case using more (larger case volume) or less (smaller volume) may get to the same level, there is usually more net velocity (at the same pressure) when there’s more room in the case. If it didn’t matter then other things done to expand case capacity (like shoulder angle changes) wouldn’t matter either.

cartridge case capacities
Case capacities vary, and, as you can see, a good deal. These .223 Rem. are each filled with an equal amount of spherical propellant.

Three: Precision standards. What do you expect, what are you willing to do to get it? After enough experience with enough different brands, that is a legit question. Some brass is “better” out of the box. Cost usually reflects on initial quality. Paying a premium for premium quality, which is three things: consistency, consistency, and consistency. That consistency will primarily, or at least measurably, be in wall thicknesses. The choice there is to buy it or make it. That choice is a balance between effort, value of time, and proven results.

lapua brass
Consider first-use or re-use? Good stuff! And you’ll pay for it! Lapua cuts case prep down to sizing: the case heads are milled, the primer pockets and flash hole are reamed. It’s also a little thick and a little soft. Single-shot-style use in a bolt-action, can’t really beat it, but my AR15 Service Rifle beats it to death.

After using enough different brands with varying levels of costs and claims, I think the most honest thing I can tell you is that you’ll likely end up with the overall “best” brass case you can have shopping in the middle, plus a little, and then getting to work on it. A good commercial “name” brand can be made at least effectively close to the dimensional equivalent of a premium brand, like Norma, but it’s not without effort.

Before spending any time weighing or otherwise sorting cases, do all the prep work you plan beforehand. If any prep involves material removal, even trimming, that influences weight accuracy and, therefore, the viability of segregation by same.

Recommendations?
Yes. And no.

About the time you decide there’s some certain way some certain thing is, they up and change it. I avoid making too many lumped-together, generalized statements about particular brands because of that. However! I can tell you that some of the “better” brands of brass also tend not to hold up as well, or won’t if there’s much working load to load (expansion, sizing). I’m thinking here of the better-known European brands, like Norma and Laupua. Those are near about dimensionally flawless out of the box, but they tend to be a little on the thick and soft side. I use Norma in my .22 PPC because the cost is worth it. If I drive from Mississippi to New Mexico to shoot a match, that’s the least of my expense.

nosler brass
This isn’t cheap either, but I have had good results with it. Nosler is, or can be, ready to go out of the box, including case mouth chamfer. It’s held up well for me in semi-autos.

This is also the reason that every serious competitive shooter I know says to buy up as much of one lot as you can, if you know it’s good stuff. That’s for all components.

Sometimes brass chooses you!

As said last time on the “Multiple Gun” loads, if you’re mixing brass things like case volume do factor. As also suggested then, the best solution is to pick a load that’s in around the 80- to 90-percent range of max. I mix brass all the time. I shoot quite a lot of factory ammo and, yes, I save each case we can retrieve. I clean them all, size them all, and fill them with a “compromise” load I worked up for can blasting. The need for those excursions is not quarter-minute precision.

If you’re looking to save as much as you reasonably can and still get “good” cases there’s honestly nothing wrong with Lake City. The more recent production 5.56 measures pretty well, and it’s tough, and relatively high-capacity. I sho can’t vouch for any other headstamp on mil-spec ammo beyond “LC.” However! I suggest purchasing it prepped. Avoid “range dump.” A big issue with once-fired is which chamber it was first-fired in. Avoid .308 Win. (7.62 NATO)! You DO NOT want to deal with M60 or Minigun leftovers.

lc nm brass
This is LC Match 7.62. No primer crimp! For reuse in a semi-auto, it has the right stuff, which means made of the right stuff: it’s hard, tough.

Start HERE on Midsouth. Great deals! Great brass!

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

Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE

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RELOADERS CORNER: Multi-Rifle Loading

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If you shoot the “same” load for different rifles, here’s a few ideas on getting the most out of it for all of them. READ MORE

multigunj reloading

Glen Zediker

I have a few rifles…

Every time I do a new book I have more. This last time around, in writing America’s Gun: The Practical AR15, I built 10 AR15s, and half of those have the “same” chambering (5.56 NATO). My choices that I can case and then uncase any afternoon for some range time might all have the “same” chamber but they’re each and all, in some measured amount, different.

That’s literally in measured amounts, and more in a minute.

If you (like me) really don’t want to load separately, store separately, and use separately, then the only real choice is to employ a “lowest common denominator” tactic. With only one exception, I don’t load uniquely for any of these guns. I pretty much just want a sack-full of ammo at the ready. The one I load uniquely for has a tuned gas system (it’s a practical competition “race gun”).

old and new AR15
Both straight up NATO chambers, but the little one won’t run what the big one will. It’s a gas system architecture difference, and a little more challenge to find a “universal” load. Rifle-length gas systems like on my retro “602” M16 (left) are, by the way, more tolerant of load variations than tricked out short guns like the brand-new USASOC URG-I (right).

Variables
Assuming all the rifles have the “same” chamber, meaning only that the barrel stamp is the same, there still exist differences. There are differences reamer to reamer, and, depending on the operator, there might (will) be differences in headspace, and leade. They’re likely to be tiny, but tiny can matter. Some manifestations of pressure have some to do with the barrel bore (land diameter for instance).

I measure spent cases for all the different rifles. They don’t measure nearly all the same! Of all the set-by-sizing dimensions, cartridge headspace has shown the most variation in my samples.

That, also, is a very important dimension to set. As gone on (and on and on) in RELOADERS CORNER, the idea is to get adequate case shoulder set-back to ensure function, and also to keep it to the minimum necessary to prolong case life. The minimum necessary runs from 0.003 for a semi-auto to 0.001 for a bolt-action.

To set this dimension for multiple rifles that use the same batch of ammo, the means is pretty easy to anticipate: find the gun with the shortest headspace, set the die to set back the case shoulder where it needs to be for that one, and live with it.

If you don’t want to give in thataway, but rather prefer (or at least don’t mind, two technically different outlooks) running multiple dies with multiple adjustments, and keeping the ammo segregated, then here’s more.

I’ve had really good experiences using a turret press. For most rifle needs, one with, say, four spots will allow the use of two sizing dies, maybe three (depending on what occupies the other locations). These dies can be uniquely adjusted for cartridge case headspace. Of course, it’s easily possible to just swap dies in and out but the turret keeps them put and saves a step.

redding t7
A turret press is a sano solution to maintaining differently adjusted dies. Redding and Lyman both make good ones. This is a Redding T7.

If you’re a bolt-gun shooter and have a couple or more rifles that run the same cartridge, and if you’re wanting to get the most from your efforts in loading for each, you might consider this next. Redding has long-made a set of five shellholders with varying heights. They allow a shellholder swap on the same die to alter case headspace, for example. There are also shims available that go under the die lock ring to provide for die body height variance. This sort of setup lets the handloader alter-adjust headspace without readjusting the die.

redding shellholders
Redding Competition Shellholder set. Five shellholders, each 0.002-inches different heights. This allows, for one, different case shoulder set-back using the same die as set.

Levels
Now. As far as lighting on a load that they’ll all shoot their absolute best with. Sorry to say, but “not likely.” There sometimes seems like there is more mystery than there is known in “why some shoot better” with one load. And when I say “load” I’m talking about the dose, the amount of propellant. What that ends up being mandates at least some effort in evaluating more than one rifle when working up to a point you’ll call it “good.”

NATO-spec ammo is hot and getting hotter! I’m talking about true NATO-spec, not just lower-cost ammo sold in a “plain box.” This isn’t about NATO ammo, but it was for me. The difference between pressure levels of NATO and, say, a commercial-made .223 Rem. “match” load are enough that two of the guns won’t even run with that. I set up these guns from the workbench respecting NATO pressures, and that, in most cases, meant firming up the “back end”: heavier buffers and springs.

My good old “do it all” load no longer exists in my current notes. Amazingly, to me at least, it’s up the velocity equivalent of about a grain and a half from what I used to bust up clods and cans with. It’s also a different propellant (now H335).

No question: pressure symptoms must also define the “lowest common denominator” when loading the same for multiple guns. Since I also have to consider reliable function in my own example, and as just suggested, I’m loading up a little nearer the edge. I carefully evaluate spent case condition from each rifle and anything that reads or appears remotely as an excessive pressure sign means I’ll knock a universal half grain off the group load.

The preceding is a specially-adapted excerpt from Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE

par15

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

LINKS
TURRET PRESSES

COMPETITION SHELLHOLDER SET

RELOADERS CORNER: Progressive Press Tips

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Progressive reloading presses are speedy and efficient ammo-creating machines, and here’s a few tips on getting the most from yours. READ MORE

Hornady AP

Glen Zediker

A “progressive” reloading press is a stellar invention. Originally conceived for use in commercial loading, the consumer segment latched onto them for the simple reason that those who consume mass quantities of ammo needed to take some of the time and tedium away from the necessary process of handloading. They were no doubt popularized with a lot of help from those involved in the (then) new sport of practical pistol shooting.

Clearly, if you think 1000 rounds is a reasonable expenditure in a day, you’ll probably be loading for your handgun on a progressive. However! They work for rifles too.

A question most have, or have had, is whether rifle ammo loaded on a progressive will shoot as well as that loaded up on a single-stage. If you have had that question, this article will help you answer “yes.” Some concerns using progressives revolve around overcoming some of the lack of control we can have using single-stage, stand-alone tools.

Hornady progressive press
Progressive presses are not just for straight-wall pistol cases. High-quality ammo can be produced on a progressive. Just need the right tooling and the right approaches. A “big” progressive, like this Hornady, can handle virtually any cartridge. I like Hornady, by the way, because of the tooling option flexibility.

The name “progressive” comes from the machine’s rotating shell plate that progressively moves a cartridge case from one step in the process to the next, from start to finish. Each pull of the press handle advances one case, another is added, and so on. A loaded round emerges at the end of the ride. Along the way each routine step in the reloading process gets done: decapping, sizing, priming, propellant dispensing, bullet seating. There are varying levels of automation, corresponding with varying levels of complexity, corresponding with varying levels of cost. Some require more or less user-supplied input (manual shell plate indexing, and so on) while others are near about hands-free, with case and bullet feeders and the like.

It’s a bench-mounted ammo assembly line.

As started on, each essential op is supplied by a toolhead that has four or more tool stations to correspond with the openings on the shell plate.

Most progressives I’ve seen arrive complete and ready to set up: all you need, all it needs. Take a look at what they’ve given you.

Get “good” dies. Most progressives will accept any 7/8-14 threaded die. Feel free, and encouraged, to use the “better” sizing and seating dies, just as you might for a single-stage press.

Hornady AP press
This’ll getcha done in a hurry! Hornady AP (“ammo plant”) with auto bullet and case feeding.

If it’s possible, upgrade the powder meter. This can often be done using a “conversion kit” if the press isn’t already outfitted with linkage that will cycle another powder meter operating handle. A good propellant dispenser always makes a difference!

Address primer pockets. The priming operation inherent in a progressive doesn’t provide the feel of a stand-alone tool. That’s not a problem at all if all primers are all seated fully. To help ensure that, I say it’s wise to run a primer pocket uniformer. That way, the pocket will be what it should be, so the priming operation should “automatically” result in a properly-seated primer. Sometimes adjustments to the mechanism are necessary, by the way.

Keep the press pieces clean and lubed. Most function issues come from neglect here. Remember that all ops revolve around the revolution of the shell plate so keep it clean and lubed appropriately. Pay attention especially to the priming mechanism.

And mount a progressive securely. There is a huge amount of pressure and stress involved especially on a “big” one. Think again about how many tasks are being processed each stroke, and consider those processes, and it’s clear that this big bad boy best be fastened down. It’s also noticeably easier to operate a progressive when it’s rigidly mounted. Press op feel greatly improves.

Reasons not to use a progressive? Not really, or none that really affect ammo quality. For me it’s primarily stepping up to the level of trust necessary. Single-stage? It’s all and each done one at a time. Chance for a mis-seated primer or short-charged case are more remote. Keep a close eye on results using a progressive. Don’t get either in too big a hurry or complacent. I check each round after the fact, looking mostly for high primers.

The more pre-progressive case prep you do (maybe) the better. Much of that depends on what you routinely do to or for cases. Trimming, for instance, primer pocket cleaning, primer pocket uniforming, and on down the list. The main reason I don’t use progressives more than I do is because I radically slow them down! All those ops are stand-alone station processes.

decapping die
Prior decapping is wise. I recommend this op prior to case cleaning (gets the primer pockets). But decapping prior to putting the cases on a progressive eliminates a huge amount of grit that otherwise will get onto and into the mechanism. Pay close attention to progressive priming parts: look out for any debris, which could conceivably detonate a primer; that can and has been catastrophic. And take care filling primer tubes! Know when to stop, know when they’re full.

The closer your starting point (sizing a clean case) is to your ending point (seating a bullet) the better a progressive will reward you.

Last: Keep a close watch on supply levels! The efficiency of a good progressive creates a time warp for me. I am always surprised how quickly primer and propellant supply empty. Warning buzzers are most welcome!

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Glen’s books, Handloading For Competition and Top-Grade Ammo, are available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com and check out more articles and a brand new book on AR15s! HERE.