In doing higher-volume loading, one fear is “what if” and that refers to having made a mistake… READ MORE
Not much worse than a bunch of newly loaded rounds tainted by potentially problematic imperfections. I’ve had more of these with pistols than rifles. Not sure why…
Glen Zediker
So you’ve put, say, 500 rounds together and there’s a flaw, and this may (usually always) be constant and consistant throughout. Or, maybe something changed during, someting shifted, at some point from then at the start to now at the end.
This can happen, and you’re fortunate indeed if you have no stories to share.
Before getting far into what it was and what was the influence or effect we’re now facing, this next will suggest a few things to check beforehand to head it off.
I don’t know that I’ve ever read much on handloading that didn’t come with at least a few ideas on checks, checkpoints. One of the first I propellant dispensing. Using a meter for these loads, throwing charges, there’s a question about how often to stop and run a check on your volume progress against the consistency of each charge thrown into each case.
Advice I’ve seen varies and ranges from the way too often to the every now and again. Folks, honestly, I never check or double check once I’m underway. I am also using expensive meters with Culver inserts. These I have proven to meter more accurately than my scale can determine. The level of effort and attention that went into my being able to make that statement is another article, and, along the way, will be. But, if you’re not using a Culver, it is a wise investment in a minute to throw a charge or two, weigh each, and satisfying the self that all’s well. If you see a problem, if your meter won’t hold a setting, that is a huge red-flag that needs fixed.
A truly good meter takes worries about case to case weight consistency away. Get one!
I always start a session checking propellant dispensing weight. I do this more to satisfy that tiny tickle of paranoid uncertaintly than I do for any tangible reason, but we do a lot of things to fix those tickles (like look both ways before crossing a one-way street). Well. I do. I click-dial my meter to where my notes say it should be (and do the same to the other Culver-equipped meters that might be involved in this session), then throw charges with each and see the right weight from each (I usually through 4-5 at a time, weigh the pan, and divide by however many throws are in the pan). Sometimes I think I do this more to just satisfy myself respecting how good this system is.
Next I essentially check die “tightness” by confirming that the sized case dimentions are what they should me. And then also do the same for bullet seating depth.
A few tricks here come from a treat like a good turret-head press. After getting the dies adjusted to what you want for a load (this load), snugging them down and adding index marks means that, one, no there should be no movement between uses, and, also, it will be easily seen becaues of the marks. Index marks are no more complex than a paint-marker-line from die body, to lock ring, to press top. I index the sizing and seating adjustments at the top of the die also.
The fewer times anything is loosened, moved, tightened the radically greater chance it has to stay perfectly in place.
Next I triple check the bullet seating depth. By the way, I’ve also become convinced that the more initial checks made reduce any chance for an erroneous check. I look once, then again, and then again, and by then I sho should have seen all there is to see. I might overlook something, though, if I look only once, and I have done that before setting seating depths.
I triple check seating depth before starting long loading session.
The best trick I can tell you to keep tools lined up where they should be, when they have to be moved, is to handle a threaded die ONLY BY ITS LOCKING RING! Never, ever hold on the die body to thread the piece in and out the press top. Handled only by the ring, there’s no chance of movement (well, assuming that the ring was snugged in place as it should have been).
Use index lines to easly see if anything changed (moved). And handle dies only using the lock ring!
Next time we’ll look at a few things that might have gone wrong, and see about getting them fixed, or worked around.
The preceding is a adapted from information contained in Glen’s Top-Grade Ammo. Available at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads. Also, check out our new new lineup of eBOOKS!
A few factory “tricks” can be applied to handloads, if you feel a need. READ MORE
Handling precautions during round assembly and then good storage afterward extends the shelf life of reloads.
Glen Zediker
Last time we took a look at some of the differences between factory-loaded ammo and our own recipe handloads. That material wasn’t a total indictment on factory ammo as might have been expected coming from me and directed toward mine, and that’s because there are some times ready-made has its place.
One of the main-most good things that can be said about factory ammo is that it has a shelf life that, given decent storage conditions, will likely exceed that of handloads. Or not. “Not” depends on what steps or processes were applied to the handload.
Sealants
The main culprit in decreasing stored life of a loaded round results from corrosion. Some call it “sticktion,” and I’ve had it happen a few times. What it is, is the case neck and bullet corrode — stick — together. That will elevate pressure. I had a rash of blown primers from the batch I used.
There are a few ideas on how to reduce or eliminate stiction, and the first starts with eliminating the catalyst for the corrosion. Don’t touch the bullets with your bare fingers! Don’t touch the cases either. I know a few commercial loaders who produce precision ammunition and they’re all about surgical-style gloves.
I have run some tests using bullet sealant (applied as a liquid then UV-cured) and such a product will, indeed, virtually eliminate any worries over corrosion. Most factory, and virtually all mil-spec, ammo uses some formulation of sealant (bullets and primers). The reason I tried it, though, was because of the promise of greater accuracy. Glued bullets tend to produce from a little to a lot smaller velocity spreads. My jury is still out on the value of this additional step, and when there’s a verdict I’ll let you all know how it played out.
Here’s a simple and easy sealant that works well. One bottle will last about 1000 rounds. Check it out at Midsouth HERE.
There are a few different bullet and primer sealers available. For the most part, these are fairly easy to apply and none are what I’d call expensive.
Giving loaded rounds a good cleaning, and then storing them at the least in air-resistant boxes, keeps the shine on and the corrosion away for a good long while.
Some run their loaded rounds in a routine-type case cleaner, like a vibratory tumbler. That’s all good, but I suggest not using anything but “pure” media to ensure that no residues are left behind.
I use denatured alcohol and a bath towel: place the rounds on half the towel, pour on the alcohol, fold over the towel and roll the rounds around. Let them dry and box them up.
Handling precautions during round assembly and then good storage afterward extends the shelf life of reloads.
More about another factory trick — crimping — next time.
The preceding is a adapted from information contained in from Glen’s books Top-Grade Ammo and Handloading For Competition. AvailableHERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.
As with many technical ventures, ultimately attaining best success is all in the details. Here are a few never to overlook in the process of learning to reload rifle ammunition. READ MORE
Glen Zediker
First, I thank you all for responding as well as you have to this little series. I appreciate the kind comments. I know that there are many eager for me to get back to the fine points, the advanced measures, but I also hope reflecting on what I taught my son likewise has caused some pause for reflection in your own processes.
Although it may be back with other installments as things progress, I’ll finish this little series for now by going over a few process particulars that, in part, my son had more difficulty getting the hang of and, also, those that I think are absolutely mandatory to teach and coach to a new handloader, especially in creating ammo for a semi-automatic centerfire.
Case Lube
Learning how much is too much and how little is too little is an easier step if you’re using a high-quality, high-performance case lube. I know from past experience addressing this topic in Reloaders Corner that we have differing opinions amongst the readership as to the best formulation for this essential step. For me it’s always been one of the “rub-on” lubes, like Redding’s Imperial Sizing Die Wax or Forster Case Sizing Lube. I like the control, speed, and ease of die operation those products give me. However! I will freely and quickly also tell you that a lube applied using a roll-over type pad or spray delivery takes a lot of the “feel” out of this process, and that’s not always a bad thing.
There’s different products and ways and means to apply case lube. No matter what or which you choose, it takes some trial and error to learn how much to apply.
The rub-ons are so slick feeling that it’s tempting to use too little. I treat each case with a fresh dab. Charlie figured out that really wasn’t necessary, that he could go two or three without having to reup and reapply the lube to his fingers. These lubes continue to indicate, based on feel, that there’s an adequate coating, until he dang near almost stuck a case. He was correct, at least one more use per reload was possible, but there’s a measure of consistency in starting the same with each case prior to sizing. I pointed out that there was no harm done in a more ample coating because it was coming back off anyway. And then, of course, he asked about the pressure-induced dimples he was getting from using too much of it! Right: one extreme to the other. There’s a feel to this process, but it’s a balance pretty easily managed — as long as you’re not trying to see how little case lube you can get away with.
Sizing Die Set
The first on the list of “always” was learning to set the sizing die to accept those lubed cases. I mentioned this briefly before, but I am absolutely adamant about using a cartridge case headspace gage to adust the amount of sizing each case gets. I’m talking about case shoulder set back. I did a piece some time ago here about the challenge of loading the “same” ammo for use in different rifles, which are near about certain to have at least slight variations in chamber headspace. Compromise has to favor the gun that needs the most shoulder set back, and we hope there’s not a huge difference across the rack of rifles we’re using this ammo in.
This tool is a great investment and strongly recommended: Hornady LNL headspace gage. It’s how to set a sizing die for maximum utility and minimum case stress.
I promise it was not due to any sort of parental retaliation for misdeeds in the past, but I let Charlie start off with a brand new disassembled sizing die.
Setting set back is a tedious process that requires numerous checks. We use a Hornady LNL gage. We measured a few different spent cases from a few different rifles and, fortunately, didn’t have much variation (about 0.002). We took cases from the shortest chamber and set them back 0.004, which is what I usually recommend, and accepting that meant some were getting pushed a little more than ideal, but all were still well (well) away from the maximum the sizing die would give. That’s where the die is sitting now. I don’t recommend cutting it too close for reuse in something like an AR15. I won’t launch into a detailed look into either of those single topic-points, but following the die setup instructions that come with most sizing dies will result in what I say is excessive set back. So even a compromise still meant we were getting the least amount of brass working in sizing, and (mostly) ensuring safe and reliable function. We started with once-fired cases all from the same ammo lot, by the way.
Priming Ain’t Easy
Once again, this topic has been addressed here by me a few different times and ways in these pages, but teaching someone how to correctly, and safely, set and seat primers is best done with a “hand tool.” It doesn’t have to be a zoot-capri benchrest specialty item, but, well, to make a long story short: using the bench-mounted tools I had on hand (and trying three different ones) Charlie was retrieving and retaining essentially none of the finesse I was trying my best to explain — “Feel the primer come to a stop on the bottom of the pocket and then compress the anvil…” And it’s even harder using a press-mounted device. With anything (that I’ve used) besides a hand tool there’s too much leverage over too short a stroke to feel the progress and end of a well seated primer.
Learning to seat primers correctly is key, and something like this will teach you all you need to know about that process. This Lee-brand hand tool is not expensive but it honestly seats primers as well as anything I’ve yet used. There’s an overage of leverage in other style tools and that precludes developing the feel necessary to ensure consistent success.
We’re not nearly shooting Benchrest, but for the sake of consistent ammo performance and safety all primers should be seated well, which is to say well-seated. And, especially for a semi-auto, they all must be seated to below flush with the case head.
I handed him said hand tool and after a scant half dozen experiences, he had it down pat. A serious light went on and smile appeared: Oh! Moving then to bench-mounted tool he had learned what he needed to know, or had felt what he needed to feel, and instinctively slowed down and lightened up and got the same good results. The lesson here is that if you’ve never used a low-leverage hand-operated priming tool, try one. You might not want to stay with it, especially when faced with the small mountain of brass such as we collect for processing, but it will teach a thing or three.
One not so minor point we all have to learn, and definitely don’t want this one to be learned the hard way, is taking care when using primer feeds (trays and tubes).
Suitable Seating
The last thing on my list of “things that stood out” in this process of teaching Charlie to reload was setting up the bullet seater.
Another valuable gage is one that gives a way to know at which cartridge overall length the bullet touches the lands or rifling. Do not assume that because it fits into the magazine box that it’s good to go!
With an AR15, or any rifle with a detachable box magazine, the clear overall cartridge length limit is defined by what will fit into the box. There’s more to it than that. Different bullets have differnent profiles and ogive dimensions. This influences how far from the lands or rifling the first point of bullet major diameter (that which coincides with land diameter) will be when the round is chambered. I recently wrote about having some “sticking bullets” in a rifle. This was a factory load but the bullet profile, overall cartridge length combination exceeded clearance — the bullets were jammed into the lands. Not what you want, unless of course you know what’s what you want (and that’s another topic entirely).
A fair number of .224-caliber bullets may touch the lands if seated to an overall cartridge length that fits the magazine box, if that’s the only criteria used to determine round length. These have to be seated more deeply, resulting, of course, in a shorter overall round length.
Never (ever) assume! Mil-spec, and most other, .223 Rem. rounds, for instance, will have the ballpark 2.250 inch length (in my notes the max is 2.260) that closely but adequately clears the box walls, but some I’ve used have to be down a good 0.025 under that to avoid sticking the bullet into the lands. I’ve seen this be most prevalent in lighter weight varmint-style bullets. Check it to make sure. And, as long as there is a gap between the bullet and the lands, all is fine.
The tool to use is a Hornady LNL OAL Gage. Once again, the only measuring tool needed for use with either of the gages mentioned is a decent caliper.
The preceding is a adapted from information contained in from Glen’s books Top-Grade Ammo and Handloading For Competition. AvailableHERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.
A popular topic in these pages, and for good reason: it can make a big difference in rifle accuracy! Read more about it HERE
Pretty much all bullets respond to seating depth changes. Long or short, for maximum accuracy it’s worth the effort.
Glen Zediker
Every time I do an article here in Reloaders Corner on the topic of bullet seating, I always see at least a couple of comments from readers about their experience and preferences with bullet seating depth. Those usually involve or revolve around seating a bullet so it is touching, or is nearly touching, the lands or rifling when the round is chambered.
This is a long-standing “trick” well known in precision shooting circles, like those competing in NRA Long Range or Benchrest.
Seeing What You’ve Got
First step, absolutely, is determining what the bullet seating figure is for your particular bullet in your particular chamber. This length is most often referred to as “dead length.” That’s a pretty ominous-sounding term! It’s not really perilous, but there is a little danger involved, which, mostly, is one point to respect. That point is that when a bullet goes from just off to just on — actually touching the lands — pressure will (not may) increase. Reason is that the previous gap-valve effect closed so burning gases are effectively “plugged up” a fractional millisecond longer. My experience with the most common small- to medium-capacity cases we’re using (ranging from, say, .223 Rem. to .308 Win.) is that this is worth about a half-grain (0.50-gr.) of propellant.
Finding It
Those who have read much in these pages have seen the Hornady LNL OAL tool. This is a well-designed appliance that will show you, in your chamber with your bullet, how far forward the lands are, or, more precisely, the overall cartridge length that will touch the lands. This amount varies and is unique! Don’t transfer figures from one gun to the next. It also changes… As the chamber throat erodes it lengthens, and so too will the overall cartridge length that touches the lands. Let’s call overall cartridge overall length COAL for sake of space.
Here’s the tool to find the seating depth that touches the lands. Hornady LNL Oal Gage.
There are other means but I’ve not found one more accurate. Some smoke over a bullet that’s been seated into a “loosened” case neck and gauge contact by the marks left. This, however, is likely to be “touching, plus” length.
Once you’ve got the round ready to measure, I strongly suggest doing so using a bullet length comparator along with your caliper. This is another tool that’s been gone over and gone on about here. It measures at a point along the bullet ogive rather than on the bullet tip. It’s more accurate. Now. A comparator inside diameter is usually close to actual land diameter, but, as with chambers, these are each and both unique so don’t assume anything.
More precise reads come from using a bullet length comparator to measure overall length. This is a Hornady LNL too.
Why It Works
Setting the bullet so it touches the lands does a few things, all good. One, and I think one of the most influential, is that the bullet starts off aligned with the rifle bore. As a matter of fact, it better centers the whole cartridge because there is, not may be, at least a little gap between chamber and case. If there wasn’t the round wouldn’t enter the chamber. The bullet is, effectively, supported by the lands and that has, also effectively, taken up the “slack” by locating the cartridge more concentric with the chamber and bore. It also then effectively makes up for the affronts to concentricity created by case neck wall inconsistencies and the resultant relocation of the case neck center.
Another is that that it eliminates jump (the usual distance or gap between the first point of land diameter on the bullet nosecone and the lands). Bullet wizard Bill Davis (designer of the original “VLD” projectiles, and others of much significance) once told me that his thoughts on why especially the high-caliber-ogive high-ballistic-coefficient bullet designs worked best with no jump were for all those reasons and improvements just mentioned. Plus another: gravity. A bullet floating in space, and also moving forward in this space, has that much more opportunity to engage the lands at a little angle, if only because of gravity. Always have thought about that one.
Soft-Seating
There are degrees. When we go from just on to “in” that’s another tactic some experiment with. And it has another level that’s commonly popular with Benchrest and other precision shooters. That’s called “soft seating.” What that is, is setting the case neck inside diameter to very nearly match the bullet diameter with the idea that the bullet starts out extra-long and then chambering the round finishes the bullet seating when the bullet contacts the lands. The reason for the more generous case neck inside diameter is to reduce resistance so the bullet can more easily set back and let the lands seat it.
I don’t use this tactic, but have. It’s another level of commitment and, as is often true with such other levels, demands more attention and also limits utility. One is that it clearly is only for bolt-action use. Another is that it’s for single-shot use only; such rounds should not be loaded into a magazine or fed from a magazine. For another, once loaded the round can’t usually come back out. The bullet will stay and you’ll get an action full of propellant.
Seating Depth Experiments
Now this is a process I have used throughout. Most times I find that best accuracy comes with a seating depth that has the bullet “just” on the lands. Contact is made but it’s the same pressure level as if the bullet were sitting on the benchtop. I also often have found best group sizes come at a little less than touching, and, a few times, at a little more than touching. I’m talking about 0.002-0.003 longer than dead-length. Let’s call it “firmly touching” but also a long ways away from “jammed.” These rounds often can’t be extracted.
There’s an easy way to run seating depth experiments. Here’s how I do it: I load however-many rounds at dead-length plus 0.003 COAL. I load them all that way. I then take a small press I can clamp on to a benchtop or tailgate at the range, and install a micrometer-top seating die. For max accuracy, I already seated all these test rounds using this exact setup. Take along a caliper and comparator and a fresh notebook page. I’ve adjusted the propellant charge as said earlier by dropping it a tad. Now. I also know that there’s going to be a little difference in perfected results because of this because lengths that aren’t touching the lands are running 35-40 feet per second slower, but it still shows me what’s going to work best. If it ends up being a COAL with a little gap, I’ll bump it back up.
Last
As said, the COAL that works best is going to change because the throat is going to change. Check using the OAL gage and adjust. That means the load is also changing, a little bit, each time the bullet moves forward (more case volume), and that can affect zero and velocity.
It’s a lot to keep up with.
Another note: If you’re feeding these rounds from a magazine, and running them through a semi-auto match-rifle, make sure there is adequate bullet retention (difference between bullet diameter and case neck inside diameter, go good 0.003 inches). Don’t want the bullets jumping forward (inertia-induced). If, for example, you’re giving 0.002 hold-off, that little bit can get taken up easily and then, if the bullet gets on the lands, there’s a pressure spike.
The preceding is a specially-adapted excerpt from Glen’s book Handloading For Competition. AvailableHERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.
Knowing, and controlling, this dimension is a crucially important step in the case sizing operation, especially for semi-autos. Here’s what it is and why it matters. Read all about it!
Glen Zediker
Last time, and to start the new year off, I hit a few highlights on the first of what I think are some of the most important things to understand in reloading for bolt-action and semi-automatic rifles. A majority of those differences is in what’s allowable and possible in cartridge case sizing.
The reason I’m running these articles is to clearly define the differences in, essentially, what you can get away with (and can’t get away without) depending on the action type. Don’t confuse some of the tactics, tools, and techniques used for bolt-actions and (mis)apply them to semis. That can range from frustrating (function issues) to disastrous (blowed-up guns). I hope that these focused articles will clarify the basics before moving on to the finer points respecting each.
Here’s headspace: it’s a height based on a diameter. A .223 Rem. uses a 0.330-inch-diameter datum; the height to the diameter on the case shoulder that equals 0.330 inches is the headspace dimension, measured from the case base (this is measured from the bolt face to determine headspace in a rifle chamber). There are only 5 datums that apply to all standard bottleneck cartridges; the correct number for your cartridge will be referenced in the cartridge specifications. (Belted magnums and rimmed cartridges are different stories, for a different story.)
Following on that, here’s one: cartridge case headspace. A rifle chamber has a headspace; a cartridge case has a headspace. The second cannot exceed the first. Here’s how it goes:
The area in point is the case shoulder, the area between the bottom of the case neck cylinder and the case body. There are two dimensions associated with case headspace: the diameter of the “datum” line, and the height (measured from the case base) to that line. So, headspace is determined by the location of the datum line. There are only 5 datum diameters in use over the range of bottleneck rifle cartridges. Datum diameter will be indicated in the cartridge description in any good loading manual. (Belted magnums, which headspace off the belt, are the exception, and different stories, and so are rimmed cases.)
Chamber headspace is determined by the chamber reamer and also the one operating the reamer. There are SAAMI standards for all standard cartridges (which are coincidentally those having SAAMI specs). Ammo manufacturers set their cartridge case dimensions to work within those same specs, and almost always with (literally) some room for variations. That means that, usually (and, again, I’m talking about factory-chambered rifles) the cartridge case headspace will be a little shorter than the rifle chamber will accommodate.
When a round fires, as is by now well-known, the case expands in all directions under pressure, swelling and conforming to the chamber, then retracts immediately afterward when pressure dissipates. Since brass has a plastic property, dimensions are not going to return to exactly what they were prior to firing, and that’s what all the sizing tools and operations seek to rectify. So, among other changes, the case shoulder will have “blown forward,” after having snugged up into that area of the rifle chamber. That will have moved the datum line upward. As hit upon last article, semi-automatics are notorious for exhibiting a little more than they “should have” in expanding, and that’s because there’s a little (to a lot) of pressure latent in the case when the bolt starts to unlock and move rearward. This can effectively create additional space for case expansion within the chamber. The case shoulder measurement after firing in a semi-auto might actually exceed that of the actual chamber headspace, or, at the least, be a little taller than it would have been in a bolt-gun having the exact same chamber dimensions. The hotter the load, the more gas system pressure, the more this might show.
Get a few de-primed once-fired cases and a gage and get to work. Here’s a Forster Datum Dial gage. Works well and works for all standard-architecture bottleneck cartridges, as does the Hornady LNL. Each or either gives a “real” headspace number (although it’s not perfectly congruent, without mathematical manipulation, to the figure from a headspace gage used for chambering; that doesn’t matter though: as long as the gage is zeroed it shows the difference, and that’s what matters). By the way, the old standard “drop-in” style case gages might keep ammo safe, but won’t provide this sort of detail in information. The numbers we need to get from our gage are these: new, unfired case shoulder height (where we started); fired, unslzed case shoulder height (where we went to); sized case shoulder height (where we need to get back to).
To be rechambered, this case has to have its case shoulder “set back,” which means that the sizing die has to contact the shoulder area enough to budge it, bump it, down to a tolerable height. Here next is how to find out what that “tolerable” height is.
The process of adjusting a sizing die to produce correct cartridge case headspace is plenty simple and easy, and requires a specialty tool (and you knew that was coming): a gage to determine datum line height.
First, and important: this has to be done on the first firing of a new case, either a factory-loaded round or your own creation. For more conclusive accuracy, measure 4-6 cases, and, very important: de-prime a case before taking a read (the primer might interfere).
Measure a new case. Write that down. Measure your fired case. Write that down.
Again, in a semi-auto the chamber might not actually be as long as the fired case reading says it is. In a bolt-gun, the post-firing case headspace dimension is going to be a closely-accurate indicator of the chamber headspace (but always subtract 0.001 inches from any reading to account for the predictable “spring back” in brass).
To set the die, take the fired case reading and reduce it. How much set back? I recommend 0.003-0.004 inches for something like an AR15 or M1A. That’s playing it safe, considering, again (and again) that there may likely have been additional expansion beyond chamber dimensions. I’d like to see folks set back their bolt-guns at least 0.001, but I’m not going to argue! I don’t like running sticky bolts.
Thread the sizing die down to touch the shellholder when the press ram is at its highest point of travel (whether it “cams” or not). Then back the die up (off) one full turn. Lightly seat the die body lock ring against the press top, and repeat the following process: lube and size the case, check the headspace; adjust the die downward, check the headspace. Rinse and repeat. For a 7/8-14 thread, which is virtually all presses, a full turn equals 0.0714 inches. That little nod of knowledge helps keep from going too far too soon, and also shows just how fine the adjustments get right at the end. When you think you got it, size a few more cases and read them. When you know you got it, lock the die ring. Note: the expander/decapping assembly was removed from this die, for one, because t doesn’t factor in establishing headspace, and because I set it all up separately on a new die. Headspace is the first thing I set.)
A little extra space ahead of the case shoulder helps ensure safe and reliable functioning in a semi-auto, and also, importantly, reduces the chance that the case might bottom out on the shoulder area in the chamber before the bolt is fully locked down. Firing residue in a semi-auto chamber is also effectively reducing chamber headspace, and that’s another reason for the little extra shoulder set-back. Keep the chamber clean!
Don’t just set the die bottom flush against the shellholder and commence to shucking cases! Most die makers provide that as instruction, and some say drop it down another quarter turn or so beyond that. That’s excessive. Here’s the read I got from flush die-shellholder contact on a new Forster.
Why not just set the shoulder back, for either action type, to what the factory set for the new case? Doing that really wouldn’t affect load performance, but, in my belief, deliberately creating what amounts to excessive headspace is not wise. It’s just that much more expansion, that much more “working” that the brass has to endure, that much shorter serviceable brass life. However! That’s not nearly as bad as leaving the shoulder too high! That’s dangerous.
NOTE: Bolt-Gun Only! Do you have to do this with a bolt-gun? I say yes, but freely admit that, at the least, from zero to “just a tic” is safe enough. What you do need to do is know what you’re getting! For a bolt-action it is possible, and some think wise, to determine the necessary case shoulder set-back based on what is needed to close the bolt on the resized case: adjust the die down a tad at a time until the bolt closes. Depending on how stout the load is, it might be 2-4, or more, firings before the shoulder needs to be set back for a bolt-gun. But, rest assured, it eventually will. Just keep up with it. I think the bolt should close easily (and if you’re having issues with that in your handloads, there’s the first place to look for a cure). It’s really not possible to follow this plan with a semi-auto because the bolt will close with much greater force during actual firing.
The information in this article is from Glen’s newest book, Top-Grade Ammo, available HEREat Midsouth. Also check HEREfor more information about this and other publications from Zediker Publishing.
There are essential differences in loading for these action-types. It might not matter if you know all about the one, but it is critically important to know about the other. Find out which is which… Keep reading!
Any rifle with a gas operation system has to, well, have gas to operate! When it gets excessive is when the problems start. That’s another article, but the effects of the operating system is the basis for both the cautions in this article.
By Glen Zediker
Over the time I’ve been producing Reloaders Corner here at Midsouth, my focus has been exclusively on reloading for rifles, and, within that, primarily for semi-automatics. The reasons for that are based on two things, one is an assumption and the other is plain old fact. First, semi-autos are popular and represent the interest of a great number of new reloaders out there, and that’s my assumption. It doesn’t take long to come to the conclusion that high-capacity magazines and long days at the range combine to get expensive in a hurry! But the biggest reason I focus most of my material toward the needs of the semi-automatic rifle is because there are decidedly important differences in some decisions the handloader makes when tooling up for one. That’s the fact. Not knowing or respecting these differences can be disastrous.
I set out to be a sticker for clarity, but sometimes I overlook making more pointed references to these differences, when there are options associated with any one topic. I judge that based on the feedback I get from you all respecting tooling and component options. I want to start the New Year with this article, which I think contains some basic and important information to always (always) keep in mind. Hopefully it will also reduce questions, and I sure hope confusions. It also seemed to be, judging on feedback, the topic that created the most questions and comments.
Essential: When a round fires, the case expands, in all directions, as much as it can to fit the chamber. Since brass is elastic (can expand and contract) and plastic (can expand and retain that expansion) that last attribute, plasticity, results in a spent case that’s closer to rifle chamber dimensions than it was to its factory-new figures. Since many factory barrels have relatively generous chambers compared to most custom-done barrels, that’s either good or bad, depending on whether it’s a semi- or bolt-gun, and also depending (a lot) on what anyone buys into.
So, for reuse in a semi, that now overly-dimensioned case has to be brought back closer to nearer-to-new condition than it does for a bolt-gun. Has to be. Otherwise it might not chamber smoothly or fully.
Due to the greater amount of case expasion, and also due to the need for smooth, easy feeding, any and every case used for a semi-auto should be full-length resized.
It’s important to understand that any semi-auto (at least any I’ve yet had experience with) has the cartridge case in a different condition right at the start of the extraction cycle. In a semi, the case is still holding pressure when the bolt starts to unlock. Bolt-gun, it’s all long gone by the time the knob gets lifted. That’s why a freshly spent case from a semi will raise a blister and one from a bolt-gun is cool to the touch. This pressure creates what amounts to greater case expansion in a semi-auto. Depending on the particular rifle and other factors that will get addressed in other articles, this varies from a little to a lot. The spent case measurements from one fired in a semi may not accurately reflect chamber dimensions, as they will with a bolt-gun.
The reason there’s still some pressure within the case when the bolt starts to unlock is because that’s how a gas-operation system functions. If all the pressure was gone the action wouldn’t even open.
A bolt-gun can be neck-only sized. I honestly don’t think this is a worthwhile practice, and I’ll talk more about that in another article, but as long as you’re willing to get a handle on case dimensions (so you know it’s still within specs to fit your chamber) it’s perfectly safe, and usually results in good group sizes.
Which brings us to the second essential difference in bolt- and semi-: Most semi-automatics, especially what is probably the most common (AR15 family) is very sensitive to gas port pressure. Gas port pressure is an actual measurement, but that’s not important to know, not really. What matters is understanding the effect of too much port pressure, and that is too much gas getting into the operating system, and getting in too quickly. That creates what most call an “over-function.” The action tries to operate, and the extraction cycle starts too early. There’s a lot of gas still binding the inflated case against the chamber walls. Many ills: excessive case expansion, excessive bolt carrier velocity, extraction failures (extractor either slips off or yanks the case rim, which can come off in a chunk).
Semi-autos are way on more sensitive about propellants, and, specifically, the propellant burning rate. Here is the set I use for my .223 Rem. competition loads (aside from a propellent that’s running in the range of the H4895, tough cases and thicker-skinned primers are part of the picture too).
From a reloading perspective, regulating gas port pressure is all in propellant selection. The burning rate range that’s suitable for semi-autos varies with the cartridge, but for both .308 Win. and .223 Rem. I cut it off at the Hodgdon Varget, Alliant RE-15 range: those are fine, but don’t go slower! Bolt guns don’t care about any of that.
Some will (certainly) disagree, but this is about the slowest-burning propellant I would suggest for .223 Rem. As a bonus, it’s also one of the highest-performing.
THE SHORT COURSE: Think “smaller” and “faster” when tooling up for sizing and choosing propellants for use (really, re-use) in a semi-auto. Smaller case sizing, faster-burning propellants.
This will all be hit on in upcoming articles in far greater detail but…
SEMI-AUTO: full-length case sizing, case shoulder set back at least 0.002 (from what a gage indicates as the fired case dimension), case neck “tension” at least 0.003 (difference between sized case neck outside dimension and loaded case neck outside dimension). Propellant selection: not too slow! Contrary to what logic might suggest, slower-burning propellants produce higher gas port pressures because they “peak” farther down the barrel.
BOLT-GUN: neck-only case sizing is (usually) okay (that means no case body sizing). Case shoulder set back: can be fine-tuned based on what’s necessary to easily close the bolt (ranges from none to “just a tad”). Propellant: doesn’t matter! As long, of course, as it’s suitable for use in that cartridge.
Check out some tools HERE at Midsouth
The information in this article is from Glen’s newest book, Top-Grade Ammo, available HEREat Midsouth. Also check HEREfor more information about this and other publications from Zediker Publishing.
Don’t lose sight of the basics when making tool, dimensional, or load choices. Here are four unchanging “musts” to make your results the best they can be. READ ON!
Bandwagon! I jumped on this one as did a whopping lot of others. Moly coating got a huge amount of attention and, indeed drastically improves bullet performance. The furf died down, though, after we discovered it had its share of problems (some were and some weren’t willing to accommodate or work around them). I still use coated bullets but now it’s Boron Nitride.
Glen Zediker
I have been basing some of my topics for this department on correspondence, and here’s another. Someone wrote asking me for a compare/contrast on the two handloading-specific books I’ve written, and the essential question revolved around whether or not the older of the two had been “updated.” Concerns were over inclusion or exclusion of new tools and propellants, and other components, and reloading techniques: essentially whether the newer book was better just because it was newer. Hmm… I thought long and hard about all that.
My answer, strongly self-paraphrased, was that there were always going to be new tools and propellants and bullets and cartridges and primers, but “what matters” in learning how to make ammo gin (accurately and safely) hasn’t really changed. Those who know my work over the past twenty-something years know I’ve never been eager to step up on a soapbox and proclaim coronation of the latest-greatest propellant, bullet, or even cartridge king. Instead, I’ve done my best to help folks learn how to judge merits and values of new things, based on a thorough understanding of all the old things. But this isn’t about me and it’s not just shameless self-promotion. It’s an overview of what I really think matters: it’s an effort to put into perspective the potential merits of all the new things.
Choosing the appropriate case and neck sizing die, and then learning how to correctly adjust it, for the needs at hand, which really means for the rifle the ammo will be used in, is another essential element in good loading.
For me, the four most important things to achieve with a handload are, one, that the case has been sized correctly and appropriately for the rifle; two, that care has been taken to ensure that the round is concentric (more in a bit); three, exercising some discretion in bullet velocity (also more in a bit); and, four, taking steps from reloading to reloading to maintain consistent performance.
Then there is an almost never-ending slew of finer points within all these points. And one ton of tools.
What I “know” about a load combination hasn’t come from one afternoon at the range. It’s often come from years. I have seen a whopping lot of bandwagons competitive shooters have jumped onto and off of. Newly hitched wagons are still rolling strong, departing continually. It is very important to have a set of components and processes and load structures to fall back on, which really then means a set that you can move forward from.
One of the “big four” goals I set for handloads is concentricity, run-out. Most of the tool and die upgrades I ever suggest making, as well as many case-preparation steps, seek to improve the straightness and centeredness of a loaded round. “Start in the center, finish in the center.”
I look at new things from a perspective of how and how well I can apply one of them to satisfy the same old needs. These needs are a filter, more or less, that helps determine if the new things are indeed improvements, or just new.
I am a competitive person. Our club CRO, Col. Floyd, once announced to the crowd at a local High Power Rifle tournament that I could smell gold-plated plastic through four feet of reinforced concrete… I admit to the truth in that. So, I am in no way suggesting that new things aren’t good, that we should all stay only with what we know. I’m always looking for ways to do better; but for me it’s not been so much trying something new, but rather taking another step using what’s been working pretty well for me thus far. That usually involves more focus on consistency.
I have a lot of stories about ultimate failures eventually resulting from initially wild successes, including lost championships, but the only value telling any of them would have is to make me sound way too old school. They are, again, never (ever) taken to mean that new things aren’t worth pursuit. Just shoot a lot of it under varied circumstances before packing it up along with the suitcase to attend a big event.
Back to setting down some tangible point to all this: most tool choices and case preparation steps I take have a goal of improving loaded round concentricity, which is to say centeredness or straightness. No doubt about it, a bullet looking dead center into a rifle bore is going to shoot better than one that’s cockeyed.
Cases with more consistent neck wall thicknesses, sizing die designs, and bullet seater designs can either enhance or detract from concentricity. Likewise, operations like outside case neck turning are done ultimately to improve concentricity. It matters!
The comment earlier about not getting too greedy for speed gets preached a lot by a good many, and the reason is avoiding anything that’s edgy. “Edgy,” to me, means something that’s going to take a turn for the worse on a day that’s 20-degrees warmer, or (in the case of the lost event mentioned earlier) 20-degrees colder.
Don’t get greedy on speed! An essential component in handloading success is consistency, predictability. Find a “tolerant” propellant, which means it demonstrates flexibility: shoots well at a little lower-than-maximum velocity, and shoots the same at different temperatures. No matter how small the groups were in testing, if pressure starts spiking due to some unaccounted for change those great test groups are likely to open up.
The best advice I can offer on this is, first and most obvious, use a little discretion working up a load to a ceiling higher than what equivalent-spec factory ammo can produce. It can take more than a few case and primer inspections to know if a “max” load is truly safe. Next is to get to work on finding a propellant/primer combination (mostly propellant) that’s showing good accuracy at less-than-max velocities. By that I mean I will not trust anything that seems to shoot well only when it’s running “hot.” Accuracy is, after all and always, what ultimately defines success.
(Since this piece is kind of a “year-end” thing, I plan to start the new year up fresh with a whopping lot more about specific new (and old) things that will help ensure you’re getting the most you can from your time spent at the loading bench.)
The information in this article is from Glen’s newest book, Top-Grade Ammo, available HEREat Midsouth. Also check HEREfor more information about this and other publications from Zediker Publishing.
Some confuse these operations. Don’t! Here’s what each is, and isn’t…
Glen Zediker
I get a lot of questions. I always answer each one, and in doing so that experience reminds me of the wide span of topic knowledge needed to be a successful, and safe, handloader. I make an effort not to assume any level or depth of anyone’s understanding of any topic I might address. At the risk of “offending” all the experts out there by wasting their time with fundamental starts to technical pieces, I’d dang sho rather bore them than shortchange a newcomer out of elemental information.
I told folks in my last book that “grains” refers to a propellant weight, not a kernel-count. Right. But I’ve fielded that question more than once. That’s not, in my mind, a “stupid” question. Truth: The only stupid question is one that’s not asked, when there’s a need to know.
So, that was leading into this: Here’s a question I got just yesterday that sourced via someone who wasn’t even a little bit uneducated in the need for finer points of case prep. This fellow was confused about the relationship between inside case neck reaming and outside case neck turning. Here’s a longer version of the answer I returned to him —
First, there is no relationship between inside neck reaming and outside neck turning, and by that I mean they are not a combined process. As a matter of fact, these should not be combined!
They can be confused because they both ultimately accomplish the same thing, the same basic thing: each process removes material from a cartridge case neck cylinder, and that makes the case neck wall thinner. These two ops, however, are done for two different reasons.
Inside neck reaming is a treatment to thin excessively thickened case necks after several firings. If the neck walls get too thick, the outside diameter of the case neck might not have adequate room in the chamber to expand to release the bullet. Excess pressure! Shown is a Forster-brand accessory for its case trimmer. IMPORTANT: “Standard” case neck reamers are for use only on fired but not resized cases! Exceptions are custom-size reamers, and I own a few of those that get use from time to time, but, as was said for tight-necked rifles, if you know about that then you already know about this…
An inside case neck reamer is intended to relieve excess material from case necks that have thickened excessively through use and reuse. Brass flows, and it flows forward.
Important! Most “standard” case neck reamers are intended to be used on fired, but not yet resized, cases! In other words: Use the reamer on the fired cases as-are. Do not use one on a case that’s had its neck resized because that will cut away way too much brass.
Another application where inside reaming is frequently recommended is in forming operations that require a reduction in case neck diameter. When a case is “necked down,” which means run through a sizing op that creates a .243 caliber from a previously .308 caliber, for instance, the neck walls thicken. An appropriately-sized reamer makes the shortest work of this tedious but necessary job. Most forming die packages either include or make mention of the specific-size reamer to use.
Outside case neck turning is done to improve the consistency of case neck wall thickness around the cylinder. It’s a step taken to improve accuracy. Outside case neck turning should be done only on brand new (unfired) brass. It’s more precisely effective and easier because that’s when the alloy is at its softest.
Outside neck turning is a “precision” case prep step that improves consistency of the case neck wall thicknesses. It can be done a little bit to clean up “high spots” and make the cases better, or full-area to make them nearly perfect. That, of course, also makes them universally thinner so your sizing apparatus might need to be dimensioned differently to maintain desired case neck inside diameter to retain adequate grip on the bullet.
There are specific, custom combinations that require a smaller than standard case neck outside diameter. The “tight-necked” rifle, which is just about exclusively encountered in Benchrest competition, has to have its brass modified to chamber in the rifle. The neck area of the rifle chamber is cut extra-small to provide a means to attain a “perfect” fit and minimal case neck expansion. If you’re into this, then you already knew that…
So, the primary role and use of an inside neck reamer is as a safety precaution; its secondary use is as a prep step in case forming. The primary role and use of an outside neck turner is to improve the consistency, quality, of a case neck cylinder. The idea is that more consistent wall thickness leads to a more centered case neck. And it does. Reaming does zero to improve consistency. Reaming just makes a bigger hole of the hole that’s already there; it doesn’t relocate its center.
The way (or one way) to tell if your cases need a ream is to take a fired case and see if a bullet will freely drop through the neck. If it won’t, they’re too thick. Thrown them away or refurbish them with a reamer. Resizing won’t change a thing.
Combining these ops might create a safety issue because the necks might get too thin, and that could mean there wouldn’t be enough grip on the bullet. Point is, ultimately, that reaming and turning are not equivalent even though they might seem to be doing the same thing. One is not a substitute for the other. It certainly would be possible to remove metal from the outside of the neck cylinder to overcome the effects of thickened necks, if (and only if) the neck is sized again using the usual die apparatus. When that’s the goal, though, a reamer is lower effort, faster, and less expensive to buy into.
Very important! Always (always) culminate either operation by running the cases a trip through the sizing die you normally use.
Here’s a few ideas on how to proceed in load testing to find the safe maximum velocity, and keep it safe…
We’ve chosen the sometimes twisting path to becoming handloaders because we want to improve on-target results. The difference between a handloader and a reloader? My wise-crack answer, which is honest, is that handloaders start off with new brass… We’re not about to shoot factory ammo.
Part of the process of developing the load we’re seeking is learning how to safely set a cap on its pressure. Most of us don’t have pressure-testing equipment, so we rely on measurements and observation to know when we’re at the limit. The goal often, all other things being the same, is to find the highest velocity we can get. Less drift and drop, shorter time of flight, all good. However! Knowing that the maximum tested velocity is also going to be safe over the long haul is a much narrower line to walk.
There’s not room here to cover every pressure check, all the symptoms that can point out over-pressure ammo, but I’ll share my two leading indicators: primer pockets and velocities.
Always start load development with new brass! There are a few reasons, but the leading one related to this material is that the primer pockets will be at their smallest. So. Fire the cases, size the cases, and seat new primers. It takes a little experience, which means a few times through this process, but my leading indicator of pressure is how easily the primers seat. They’ll go in easier than on the first use, but if there is much less to very little resistance felt the second time around, that load is over-pressure. Period. The case head has expanded (I put a max of 0.0005 on expansion, when it’s measured with a micrometer). The more you use the same cases and repeat this process, the sooner you’ll get a handle on the feel to know when the primer pocket has overly expanded.
My primary gauge for pressure is primer seating — how easily a new primer seats into a once-fired case. This is an indication of case head expansion. It won’t be as tight as new, but it should still be snug. A low-leverage tool, like this Forster Co-Ax, increases the feel and feedback of this operation.
Jump back, don’t step back. If you encounter a pressure symptom, come off a “whole” half-grain. Not a tenth or two. And if you see it again, come off another half-grain. Folks, if anyone thinks the difference between over-pressure and safe-pressure is 0.10-grain, that same little bit exists in the difference in 20-degrees ambient temperature with many propellants. Don’t cut it that close. Keep the long-haul in mind.
Select a temperature-insensitive propellant (related to the above). There will be one out there you’ll like. I use a single-base extruded (stick) propellant when loading for the season. The propellants I choose are coated to help reduce temperature-induced changes. That season is going to span a 50+-degree range, and I don’t want August (or October) to force me back to the loading room… Temperature sensitivity works “both” ways, by the way… Hot or cold can induce pressure increases.
Read the speed on each and every round tested. Beforehand, I have to assume you’ve gotten an idea in mind of what you’re looking to get for a muzzle velocity. If not, do that… A journey of this nature has to have a destination. If not you won’t know when you get there. If you are reading velocities more than 40-50 feet per second over a published maximum, that’s a flag. That 40-50 fps is usually about a half-grain of most propellants in most small- to medium-capacity cases. Certainly, there are all manner of reasons some combinations can vary, but, despite what your mother might have told you, you are really not THAT special…
Don’t assume anything. If you have one round out of many that “suddenly” exhibits pressure symptoms, don’t guess that it’s just a fluke. It’s not a fluke. You finally saw it. Overwhelming chances are that the load is over-pressure and has been over pressure, and the question is how much for how long? Back it off. (The way you know it might have been a fluke, and that happens, is again based on how close to a velocity ceiling it is: if it’s a real mid-range velocity load, it might have been a fluke.)
Some over-pressure indications are pretty clear. Left to right: new, nice and safe (notice there’s still a radius on the primer edge), cratered and flat, yikes! It’s another article, but not all piercings are caused solely by high-pressure ammo; an overly large firing pin hole size in an AR15 bolt contributes.
One last about primer appearances. Usually the first thing a handloader will do after firing a round is look at the primer. I do. No doubt, if the primer is flattened, cratered, pitted, or pierced that’s a honking red flag, and the immediate response is, you guessed it, come off a “whole” half-grain. However. Small rifle primers (especially some primers in some cartridges) do not exhibit the common over-pressure appearances. They can look just fine and shiny until they blow slap out. If you ever see anything that looks like a pressure symptom, back it off; however, don’t assume a load can’t be running hot if the primers don’t show it.
Here’s what I mean about primer surface indications not always revealing high pressure. The middle one is an incredibly over-pressure load fired through one of my AR15 race-guns with an extra-heavy bolt carrier. Primer looks just fine. Right hand case is what happened without the extra weight. Neither case would hold a primer after this one firing.
Back to the start: primer seating and velocity are the leading indicators.
The preceding contains specially-adapted excerpts from the new book “Top-Grade Ammo” by Glen Zediker and Zediker Publishing. See it by visiting ZedikerPublishing.com.
The reloading blog where you can find articles, tips, industry news, gear reviews, and more!
