Five tips to reduce shot-to-shot bullet velocity deviation. READ MORE
I’ve spent the last two editions on velocity variations, and this one will offer some ideas on how to get yours as low as possible.
Consistent Propellant Charge
This comes first to mind, and probably comes first in most everyone’s mind, and that’s because it makes the most “sense.” Sure enough, given the effect on velocity from a tenth or two grain variation in propellant, eliminating that variable clearly takes a big step toward improving consistency.
Now comes the big question: Throw or weigh? That one there is another complete article, but the short course is, “it depends.” Bad answer! I know, but there’re more coming in a bit to add to either confusion or clarity, depending on experience. Overall, I’ll say “weigh.”
I say “weigh” because that goes a long way toward eliminating inconsistent amounts of propellant as a factor. I also say weigh because of the previously mentioned undeniable effect of haphazard propellant levels, and weighing each charge should eliminate that. Do, however, make sure that the scale is reliable. I still use an old-school beam scale. A good deal of trials and tests have not given me the confidence I need to have in many electronic scales. The short answer to satisfaction, again from my experience, is that you’ll likely get best, or at least better, results from a scale that ranges upward in cost from the “mid-priced” units, and decidedly better performance compared to the lower-priced models. I’ll also say the same for the scale-based dispensing devices on the market. I’ve used a couple that my meter beat, and a couple that were impressively accurate over a lengthy session.
Numbers 2 and 3 on my 5-point list involve the primer — ignition. This is a crucial point in the life of a flying bullet. If the primer is delivering a consistent flash to ignite the propellant column, then said column will ignite more consistently.
Uniforming the primer pocket can help. The main thing this trick accomplishes is a flat-bottomed primer pocket. The tool faces the bottom of the pocket to squareness and also cuts the entire bottom of the pocket to squareness. Most primer pockets are formed using a punch and that leaves a radius on the “corners,” resulting in a bowl-shape. Since primers are flat, they don’t seat correctly and as designed unless the primer pocket is flat. And, if the primer pocket is flat then the primer can be seated fully, which means that the anvil “feet” make correct, full contact.
If the primer isn’t seated flat and flush then some energy from the firing pin gets absorbed in finishing the primer seating, and that leads to a softer hit, and less (perfect) consistency in ignition. Yes. It’s tiny, but so is all of this!
Uniforming the primer flash hole is another trick that honestly “works” to improve velocity consistency. This is another usually punched process and can leave a burr visible on the inside of a case. A uniforming tool removes this burr and, depending on the tool design or its adjustment (if possible) will also create a little funneled area believed to better spread the initial flash to ignite the powder column. Some worry about losing metal in this area, but it will not weaken the case in any detrimental fashion.
Consistent Bullet Grip
Bullet “release” has to be consistent for the combustion behind it driving it forward to be consistent. First, that means the case neck walls should ideally be consistent so the case neck cylinder will be sized to a consistent dimension. The “spring back” in brass means thinner or thicker walls respond differently to the same dimension sizing apparatus. Again, this is a tiny thing, but they all add up.
Further, myself and a good many others have found that we usually see better shot-to-shot velocity consistency with a little more, not a little less, case neck grip, or bullet retention, however you prefer to call it. By “grip,” which some also often call “case neck tension,” I’m talking about the difference between the sized case neck inside diameter and the bullet diameter. This is something that my friend and associate, David Tubb, has done a good deal of experimentation with, as have I.
We both found that best results, again meaning best velocity consistency, came at more than 0.002 inches difference. I routinely use 0.004 for my competition loads.
One way to improve the consistency in grip is using a mandrel as a separate operation. A mandrel is pretty much a sizing button or expander that’s got a longer surface area, and, of course, is precisely sized. The idea is to use the mandrel on a case neck that is sized at least 0.003 inches smaller than the mandrel, run the mandrel into the case neck for a 5-count (important) and then withdraw it.
Another thing: I’ve got all the means but not yet had the time to experiment with adhesives. Right: That’s glue between the bullet and the case neck inside. Varying bond-strength glues have been used in honking big cartridges for military use for years and one of the pretty well demonstrated benefits is increased velocity consistency. This is a new area for the handloader and I hope to have some more information about it later on.
I really don’t like it when we sometimes (and honestly) say that it’s “more art than science.” We say that when there’s a predictable or at least reproducible combination of things that give great results. In handloading that’s something like very good accuracy and very small shot-to-shot velocity variations.
Of course it’s science! But it’s just not that well understood, meaning it’s not precisely predictable, or at least not by me and most who recite that mantra. There is a combination of case, propellant, primer, bullet, and barrel that appears magic compared to some of the other things we’ve tried. It’s all a system. Since we’ve got the barrel and it is what it is, propellant and primer are the main variables, and of course we can try different cases. I believe that it’s case volume as part of the system that has its influence on performance.
Back to the first point, ultimately the answer to the “throw or weigh” question comes as a combination of the precision of the meter and the choice of propellant. I don’t weigh charges, or not making up the loads I settled on for use in tournaments, and that’s because I see zero difference in on-target results, and that starts with seeing zero difference in shot-to-shot velocity readings in testing. I, however, have seen radical differences in on-target results with other combinations comparing weighed and thrown. However! Those loads still didn’t make my cut because, overall, the velocity consistency just wasn’t there in the first place. Folks I can tell you absolutely that just weighing each charge does in no way mean you’re going to get suitable spreads with any old gunpowder. The ultimate answer to attaining tiny shot-to-shot velocity variations, and tiny shot groups, comes from experience in doing your own testing. That’s a “said nothing” statement, but there has to be a willingness to experiment.
Beyond only experimentation, though, I think these few tips will help ensure you’re getting the best that combination can give you.
This article is adapted from Glen’s book, Handloading For Competition, available at Midsouth HERE. For more information on that and other books by Glen, visit ZedikerPublishing.com
There are a whopping lot of propellants on the market. How do you choose one? Well, usually it’s more than one… READ WHY
All we ever really want is a propellant that provides high consistent velocity, small groups at distance, safe pressures over a wide range of temperatures, and burns cleanly, and, of course, it should meter perfectly. Dang. I know, right?
Ultimately, propellant choice often ends up as a compromise and it may well be that the smallest compromises identify the better propellants. Getting the most good from your choice, in other words, with the fewest liabilities.
There are two tiers of basics defining centerfire rifle propellant formulas. The granule form can be either spherical (round granules) or extruded (cylindrical granules). Next, the composition can be either single- or double-base. All propellants have nitrocellulose as the base; double-base stirs in some nitroglycerol to increase energy.
There’s been a good deal of effort expended and applied over the past several years to reduce the temperature sensitivity of propellant. Coatings come first to mind, and I use nothing but these “treated” propellants.
This attribute is very (very) important! It’s more important the more rounds you fire throughout a year. A competitive shooter’s score hinges on consistent ammunition performance. Test in Mississippi and then go to Ohio and expect there to be some change in zero, but a change in accuracy or a sudden excess of pressure and that’s a long trip back home. It’s common enough for temperatures to (relatively speaking) plummet on at least one day at the National Matches, so my 95-degree load has to function when it’s 50.
Some are decidedly better than others in this. There are several propellants I’ve tried and will not use because I didn’t get reliable results when conditions changed. Some gave outstanding groups on target, on that day, at that hour, but went goofy the next month when it was +20 degrees. Heat and cold can influence pressure in a sensitive propellant.
Single-base extruded (“stick”) propellants are my first choice. A good example of one of those is Hodgdon 4895. These tend to be flexible in maintaining performance over a wider range of velocities, related to a wider range of charge weights. For instance, I’ll vary the charge weight of the same propellant for ammo for different yard lines. I’m reducing recoil or increasing velocity, depending on what matters more. Zero and velocity are different, but accuracy doesn’t change.
Spherical or “ball” propellants (these are double-base) are a good choice for high-volume production, and also tend to be a great choice for highest velocities at safe pressures. These meter with liquid precision. They, however, tend to be less flexible. That means they tend to work best at a set and fairly finite charge and don’t do as well at much less or more than that, and especially at much less than that. More in a minute.
Double-base extruded propellants (sometimes called “high-energy”) do, yes, produce higher velocities at equal pressures compared to single-base but also tend to be less flexible and exhibit performance changes along with temperature changes. Vihta-Vuori and Alliant are the best known for their formulations in these. Double-base usually burns at a hotter temperature (not faster or slower, just hotter) and can increase throat erosion rate. Some double-base spherical propellants claim to burn cooler. I’m not certain that this is a huge selling point, either way, for a serious shooter, but, there it is.
All propellants are ranked by burning rate. That’s easy. That’s just how quickly the powder will consume itself. All reloading data manuals I’ve seen list propellant data in order from faster to slower. For instance, if you’re looking at .223 Remington data and start off with tables for 40-grain bullets, you’ll see faster propellants to start the list than you will moving over to the suggestions for 75-grain bullets.
It’s tough to find a perfect propellant for a wide range of same-caliber bullet weights. Faster-burning propellants tend to do better with lighter bullets and slower-burning tends to get more from heavier bullets. That’s all about pressure and volume compatibility. Again, I have found that a single-base extruded propellant will work overall better over, say, a 20-plus-grain bullet weight range than a single choice in a spherical propellant.
The idea, or at least as I’ll present my take on it, is that we want a fairly full case but not completely full. I don’t like running compressed loads (crunching a bullet down cannot be a good thing), and excessive air space is linked to inconsistent combustion. We ran tests upmteen years ago with M1As and found that out. Many details omitted, but here was the end: Settling the propellant back in the case prior to each shot absolutely reduced shot-to-shot velocity differences (the load was with a 4895, necessary for port pressure limits, and didn’t fully fill the case).
Generally, and that’s a word I’ll use a lot in this (and that’s because I know enough exceptions), spherical propellants have always performed best for me and those I share notes with when they’re running close to a max-level charge. More specifically, not much luck with reduced-level charges.
Too little spherical propellant, and I’m talking about a “light” load, can create quirky pressure issues. Workable loads are fenced into in a narrower range. This all has to do with the fill volume of propellant in the capped cartridge case, and, as suggested, that’s usually better more than less. That further means, also as suggested, there is less likely to be one spherical propellant choice that’s going to cover a wide range of bullet weights. That’s also a good reason there are so many available.
With some spherical propellants, going from a good performing load at, say 25 grains, and dropping to 23 can be too much reduction. One sign that the fill volume is insufficient is seeing a “fireball” at the muzzle. Unsettling to say the least.
Spherical propellants also seem to do their best with a “hot” primer. Imagine how many more individual coated pieces of propellant there are in a 25-grain load of spherical compared to a 25-grain charge of extruded, and it makes sense.
However! I sho don’t let that stop me from using them! I load a whopping lot of spherical for our daily range days. We’re not running a light load and we’re not running heavy bullet. We are, for what it’s worth, running H335.
So, still, how do you choose a propellant? Where do you start? I really wish I had a better answer than to only tell you what I use, or what I won’t use. There are a lot of good industry sources and one I’ve had experience with, including a recent phone session helping me sort out Benchmark, is Hodgdon. You can call and talk with someone, not just input data. Recommended.
When it’s time, though, to “get serious” and pack up for a tournament, I’m going to be packing a box full of rounds made with a single-base extruded propellant that meters well. As mentioned before in these pages, I have no choice in that, really. I’ll only run the same bullet jackets and same propellant through the same barrel on the same day. I need a propellant that works for anything between 70- and 90-grain bullets.
With time comes experience, and I know I sure tend to fall back on recollections of good experiences. I admittedly am not an eager tester of new (to me) propellants. I have some I fall back on, and those tend to be the first I try with a new combination. There are always going to be new propellants. That’s not a static industry. I may seem very much stuck in the past, but I no longer try every new propellant out there. I like to have some background with a propellant, meaning I’ve seen its results in different rifles and component combinations. Mostly, I ask one of those folks who tries every new propellant…
There is a lot of information on the internet. You’re on the internet now. However! There’s also not much if anything in the way of warranty. If you see the same propellant mentioned for the same application a lot of times, take that as a sign it might work well for you. Do not, however, short cut the very important step of working up toward a final charge. Take any loads you see and drop them a good half-grain, and make sure the other components you’re using are a close match for those in the published data.
One last: Speaking of temperature sensitivity: Watch out out there folks. It is easily possible for a round to detonate in a rifle chamber if it’s left long enough. Yes, it has to be really hot, but don’t take a risk. A rash of rapid-fire can create enough heat. Make sure you unload your rifle! Here’s an article you might find interesting.
We are celebrating our 50th birthday at Midsouth! Great deals and fantastic give-aways are part of the party. READ MORE
Dustyn Brewer – Clarksville, TN
Half a century later, and Midsouth Shooters Supply is thriving. In an industry fraught with unforeseen pitfalls Midsouth has grown, expanded, and diversified themselves into an e-retailer on the rise, all because of the stewardship of Connie and David “Dirt” King.
Midsouth celebrates their 50th Birthday this July, and with it comes a time of celebration not just for the company, but for anyone who shops with them. Throughout July, customers will have the chance to take home more great deals than ever before, plus tons of prizes! Midsouth Shooters has put together several giveaways with their favorite partners, like Hornady, Nosler, Lyman, Del-Ton, Sierra, and more!
What makes this 50th anniversary even more special? This June marks the 50th anniversary of their owners. The Mayor of Clarksville, TN, Joe Pitts, has even declared a proclamation designating June 22nd as David and Connie Day! Together, they’ve forged 100 years of commitment to each other, and Midsouth’s wonderful customers. Without their guidance and steadfast values, Midsouth wouldn’t be the premier online reloading and shooting supplier it is today.
Dirt and Connie, both TN natives, celebrated their longevity in love and business with their family and friends this past weekend.
Be sure to check MIDSOUTH SHOOTERS SUPPLY daily for deals, giveaways, coupons, and more details about Midsouth’s story!
About Midsouth Shooters Supply:
What started as a modest, catalog-driven reloading supply company in remote New Market, TN, has grown into a technology driven, customer-focused powerhouse in Clarksville, TN. “It’s our 50th anniversary, and we’re growing faster than ever before,” Michael Ryan, VP of Marketing at Midsouth, recently stated, “We’re focused on keeping up with the customer, and not necessarily the competition. We buy in bulk, break down the inventory ourselves to avoid packaging fees, and pass the savings along to the customer. This has given us the opportunity to offer things like our new Flat Shipping, overpacking for hazmat items where our customer can get the most out of each order, and exciting bulk offerings like our Varmint Nightmare, Match Monster, and OEM Blemished bullet deals.”
The giveaway starts 6/26/19 and will last through their birthday on 7/24/19. Among the multitude of prizes being given away, Midsouth is pleased to offer one lucky winner a full BARREL of Hornady Frontier Rifle Ammunition! Another customer will have the chance to take home a New Nosler Liberty Rifle! Midsouth Shooters will pick several giveaway winners during their birthday week.
Witness the creation of the ultimate low-drag, high performance match bullet!
After weeks of teasers, we’re finally able to talk about the new projectile from the folks at Hornady. We actually got to visit Grand Island, Nebraska to tour the facility, and get a first-hand look at the new milled aluminum tipped bullets. This thing is beautiful!
“New to Midsouth Shooters and Hornady, the A-Tip MATCH bullets are the latest and greatest from the Hornady Ballistic Development Group! After years of research, testing, and a new advanced manufacturing process with state-of-the-art quality control measures, Hornady has created an all new Aluminum Tipped projectile. This precision machined tip is longer than polymer tips which moves the center of gravity, thus enhancing inflight stability. The aeroballistically advanced tip design results in tighter groups, and reduced drag variability.”
By using some of the most sophisticated tools in projectile development, Hornady created a bullet with a milled tip, 99% repeatable, and a Doppler Radar verified low-drag coefficient (super-high Ballistic Coefficient) with a winning blend of ogive, tip length, bearing surface, and optimized boat-tail within each caliber.
“We wanted to incorporate aluminum tips in a full line of match bullets for years because we can make longer tips than we can with polymer materials,” said Joe Thielen, Assistant Director of Engineering. “This longer tip is a key component that helps move the center of gravity of the bullet rearward, thus enhancing in-flight stability and reducing dispersion. The problem has always been the cost to produce a tip like this, but we’ve developed a cost-effective process for manufacturing these aluminum tips while staying affordable for serious match shooters. The longer aluminum tips are machined to be caliber-specific, and when coupled with highly refined AMP® bullet jackets, aggressive profiles and optimized boattails, the result is enhanced drag efficiency (high BC) across the board. Each bullet design is carefully crafted for minimal drag variability for the utmost in shot-to-shot consistent downrange accuracy.The materials, design and manufacturing techniques combine for the most consistent and accurate match bullets available.”
Right off the press, the projectiles are sequentially packed, for ultimate consistent performance, from lot to lot, ensuring your projectiles are truly YOURS every step of the way. Think of it like shooting clones of your load every time (100 in each box)! Minimal handling throughout the process means there’s less of a chance of YOUR bullet being marred, scuffed, or altered, which is why each box is packaged with a Polishing Bag for you to give the final buff to your beautiful new projectiles!
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
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.
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.
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.
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…
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
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.
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.
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.
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.
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
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”).
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.
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.
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.
We also have a link to the Shooters World site here, just in case they update the link before we have a chance to. There’s even a link for European data!
“One of Shooters Worlds biggest goals is to support competitive shooters and reloaders. Shooters World works hard to develop our own load data based on what the competition shooters and reloaders are asking for . Shooters World will always do its best to keep our prices low and Powder available. So once you change to our product there is no need to look anywhere else.” – Shooters World Powders