Trimming semi-auto pistol brass

May 2011
255
0
Woodinville WA
Anybody do this? I've just started reloading 9mm ammo after a history of reloading for bolt action rifles. Bottom line is I'd reload maybe 30 bottlenecks a month on a single stage. Now with pistol, thinking of getting into IDPA I'm reloading a lot more on a progressive!

Does anybody trim their semi-auto brass? So far my brass is just from factory brass I've fired, and only from two makers (Federal and PMC). I separate them, and reset everything from scratch for each make of case each time and they are all pretty consistent from case to case. I figure if nothing else I'll really learn my machine well resetting the dies frequently. No "How do you do this again?" moments.

So do you trim things even? Or do you just set your seating to achieve a good OAL and not care about Brass height? I'm careful by nature, but if I'm going to get into competition, I'm thinking I'm going to be using less consistent brass.

Thoughts?
 
Jan 2009
151
0
Richland, WA
I was told a long time ago that since there is no shoulder, it is not nessessary to trim the case. I don't trim any of my pistol cases, just load to the correct OAL and I have not had an issue (yet).
 
Jan 2011
29
0
Spokane, WA
Always check OAL for ANY case that you reload. Brass will strech with hot loads, and the simple act of belling the case mouth will work the brass. If you do not have the proper length and the case mouth is not square, you will not get inconsistent velocity, poor groups, etc. If you not able to get a consistent crimp on the cannelure if you are loading big bore ammo, that can cause the bullet to back out of the case under recoil, and a expensive trip to the gunsmith to fix.

Bottom line, if you want accurate ammo, check your cases and put them in the trimmer should they need attention.

My 2 cents. Better to do it once correctly
 
May 2011
288
0
NW Quadrant WA State
It would help to understand the differences in cases used for pistols.

Cases used in most all revolvers have a rim. The rim holds the case in position when it is being fired thus it "headspaces" on the rim. The case length is not critical as far as headspace is concerned.

For auto-loading pistols, almost all use a rimless case with extractor groove. This type of case "headspaces", or is held in firing position, by the case mouth. At the end of the chamber there is a slight shoulder that stops the case from sliding any farther into the barrel. For these, case length can be an issue. Too long and it won't let the cartridge enter the chamber fully and might keep the slide from going fully into battery. Too short and the cartridge could go too far into the barrel and then not have the primer fully struck thus failing to fire.

These are extreme examples as it would require an extremely long or short case to cause a malfunction in most circumstances.

It's not a bad idea to check the cases to make sure that they are in an acceptable length range but trimming is rarely needed on autoloading pistol cartridges. For my 9mm loads I use a case gauge. By inserting the case into the gauge a "too long" or "too short" case is obvious.

Case trimming is often essential when roll crimping a revolver load. This is more for uniformity of crimp than for any other reason. A short case won't crimp enough and a long case can be distorted when in the crimping phase of the process. Keeping revolver cases the same length solves this issue.

Trimming of cases for autoloaders is a topic that gets lots of varying opinions. As for necessity, as long as the case fits the chamber it's fine. For accuracy? There are so many other variables involved when shooting an autoloader that I seriously doubt that a cartridge that feeds and fires properly will have case length of a few thousandths play much of a roll in accuracy.

Cases don't grow all that much in auto-loader pistols. They usually split long before growth is an issue.

Get a Case Gauge like a Dillon or L. E. Wilson and check your cases before loading. You'll find that case length, especially in 9mm isn't an issue. The Gauge is also a good tool to make sure any round, especially if used in competition, will chamber easily.

Good Luck
 
May 2011
255
0
Woodinville WA
Trimming of cases for autoloaders is a topic that gets lots of varying opinions. As for necessity, as long as the case fits the chamber it's fine. For accuracy? There are so many other variables involved when shooting an autoloader that I seriously doubt that a cartridge that feeds and fires properly will have case length of a few thousandths play much of a roll in accuracy.

Cases don't grow all that much in auto-loader pistols. They usually split long before growth is an issue.

Get a Case Gauge like a Dillon or L. E. Wilson and check your cases before loading. You'll find that case length, especially in 9mm isn't an issue. The Gauge is also a good tool to make sure any round, especially if used in competition, will chamber easily.

Good Luck

Thanks! That's the problem I'm running into... Varying opinions. Looking at the situation logically, it really seemed with an auto that as long as the case was within standard, that a solid OAL would be all I needed.

But then of course you run across the reputable source (like a reloading manual) that says trim them to identical for the first load/reload. And yeah. That would be ideal! But damn. I'll baby my 308 and 30-06 brass because I have a max of 50 of each. But I'm looking at thousands of rounds here:hmmmm2:
 
May 2011
288
0
NW Quadrant WA State
But I'm looking at thousands of rounds here:hmmmm2:

Try a method I use to sort in to a "trim" of "no trim" batch with my rifle brass.

Take your caliper and set it to the max case length for the caliber you are working with and lock it tight. Most calipers have a set screw that will hold the jaws in position, with the gap between being the setting on the dial or digital readout.

Using the now "locked" caliper, attempt to place each and every case between the jaws. If it fits it goes in the No Trim batch. If it won't fit, then it goes into the "Trim" batch. With the 9mm cases you won't get many, if any at all that exceed .754" which is case length max for the caliber. A quick check of several cases I have fired "many times" showed them to be almost .010" less than max. and I think you'll find the same with this quick check. I'd do this when checking for splits, leaking primers (indicating large primer holes), and bulges at the case head (warning of impending case failure).
 
Nov 2009
53
0
Bothell, WA
Most autoloading brass will actually shorten with use. This is typically due to resizing. The case is reformed on the upstroke and "pushes" the brass back towards the base. Not to mention the base bulge in certain calibers taking its toll. I shoot a lot of 45 and virutally none of my brass will make SAAMI spec in terms of length. Now, before all of the "headspaces on the mouth" folks get up in arms, you need to remember that the base of the brass is fed into the extractor from the magazine and the extractor holds the base of the cartridge against the bolt face. The rim of the case never gets close to the end of the chamber; even at spec length. I know at least one very good competitive shooter who roll crimps his 45 ACP cartridges. He shoots low power loads and likes the way they feed and can live with the modest increase in pressure.
 
Jul 2011
124
0
Seattle
Case length can effect the accuracy of a 9mm, sometimes quite a bit. That "quite a bit" being very relative. To a bullseye guy, a 2.5" vs 1.5" group at 25 yards is significant. Percentage wise, it's significant. To someone shooting IDPA? No way.

IDPA is largely 10-25 feet

USPSA is largely 1-40 feet

Both have "A" or "-0" zones that are plenty big.

Some serious guys are shooting 40-60k rounds per year. Can you imagine sorting, trimming, etc. that much brass?
 
Nov 2009
53
0
Bothell, WA
Case length can effect the accuracy of a 9mm, sometimes quite a bit. That "quite a bit" being very relative. To a bullseye guy, a 2.5" vs 1.5" group at 25 yards is significant. Percentage wise, it's significant. To someone shooting IDPA? No way.

IDPA is largely 10-25 feet

USPSA is largely 1-40 feet

Both have "A" or "-0" zones that are plenty big.

Some serious guys are shooting 40-60k rounds per year. Can you imagine sorting, trimming, etc. that much brass?

On a 1911, brass makes virtually no difference in accuracy. Not my observation; Masaki, Keefer, Rodgers, Salyer, etc. all say the same thing. Masaki tested split brass once and found no difference in accuracy (or function) over new brass. COAL makes a difference as does powder, charge and bullet - and while there are rules of thumb, each pistol is different and needs its own load. Nice thing about loading for a 1911 is that it is relatively forgiving in terms of brass. As long as it will reliably function the gun, that's all it really needs to do. BTW, a competitive bullseye gun is accurate to 1.5" at 50 yards. You get to pay for those.

I don't know much about 9 mm, so I will defer to those that do.
 
Jul 2011
124
0
Seattle
On a 1911, brass makes virtually no difference in accuracy. Not my observation; Masaki, Keefer, Rodgers, Salyer, etc. all say the same thing. Masaki tested split brass once and found no difference in accuracy (or function) over new brass. COAL makes a difference as does powder, charge and bullet - and while there are rules of thumb, each pistol is different and needs its own load. Nice thing about loading for a 1911 is that it is relatively forgiving in terms of brass. As long as it will reliably function the gun, that's all it really needs to do. BTW, a competitive bullseye gun is accurate to 1.5" at 50 yards. You get to pay for those.

I don't know much about 9 mm, so I will defer to those that do.

I think how the round ultimately headspaces can be dependent on how you have your extractor setup, and how much the case length varies. In theory, you could get something that will chamber, but is long enough to change how it sits in the extractor. I know that in a 1911 extractor setup on a 9mm/.38 super/.38 supercomp is quite a bit different, and more work, than on a .45acp gun.

Here'a good article on how case length can effect 9mm accuracy. The tests here were done with a Colt Commander.
9mm reloading

My point about bullseye is it's a different game with different requirements. You can spend plenty on equipment whatever you choose to play.

Real lesson here is like anything else : go slow, be creative, don't ignore any variable until you establish it doesn't matter in _your_ gun, and change one thing at a time.

I'm working on a subsonic IDPA/USPSA legal 9mm load for my 5.25 XDm. I'll report back when I find something that works for me. For initial development, I'm using once-fired PMC brass, and will migrate the load to other head stamps until I establish weather or not it will work acceptably with mixed brass.
 
Nov 2009
53
0
Bothell, WA
No doubt about it, too long a case will not work in any firearm that headspaces off of the case mouth. The 1911 is indeed a different animal than anything else and brass does matter for other platforms. What parameter is important varies, but you have to look after brass.

One of the things I've started doing is using a Redding dual ring sizing die. Technically, the chamber on .45 ACP is tapered. However, sizing dies tend to size the bulk of the case to the min size at the mouth of the case. I think this is done to prevent bullet set back (and it's way easier to make carbide dies that size for a straight wall). So, althought the extractor holds the case back against the bolt face, it only does it on one side. This means unless you have brand new brass formed to the tapered spec, you could have the case canted in the chamber. Sizing a few thou larger at the base should relpicate the shape of the chamber a little better than full length straight sizing. I don't really know if it makes a difference, but it makes me feel better.

I wholeheartedly agree on the go slow, one thing at a time idea. You have to think things through before going forward - no bad mistakes with sorts of things we're working with.

Keep us up to date on the 9 mm experience. I admit to not knowing spit about IDPA/USPSA stuff, but isn't there a power factor thing in one of those to level the playing field? Is there a break point around sonic/subsonic that would affect the power factor calc? I do know one thing, whatever side you get on the sound barrier, don't let the bullet cross the barrier before it gets to the target. The shock wave will induce some instability in bullet and that can be the difference in points.

My current education on brass/loading is 223. I'm building up an AR for service rifle competition I'm in the middle of a steep learning curve. Fun stuff.
 
Jul 2011
124
0
Seattle
Interesting thought on the dual resizing dies. If I'm not mistaken the 9mm has a similar chamber. Right now, like I said, I'm using brass that was fired in my pistol, so the 1/4" or so of fire formed case left after resizing is likely okay. Once I start playing with "mixed brass" I might look into a tapered resizer.

You're 100% right on with the power factor. For "minor" it's bullet weight in grains X muzzle fps >= 125.000. If you've ever looked at muzzle energy or taken a physics class, this is bizzare, but it is what it is. Since it favors heavy bullets so much, I'm trying to get a 147 to work.

So far I'm at a 1.14 COL over 4 grains of Unique with cci primers. That's producing 1.5" groups at 15 yards (supported, no ransom rest), vs .5" with winchester white box. Not so clever, but it's an improvement over the 2" groups I was getting with a 1.13 COL. My measurements say I still have a safe .01" to play with, and tomorrow I'm testing some 1.145s. If that doesn't produce, I'll bump up the charge slightly. Still should have plenty of room before hitting supersonic, which for me increases perceived recoil. I have some Universal Clays I've been using in my .45s to try before giving up an going to 124s like everyone else...

These are some really soft-shooting subsonic rounds, great for competition if I can get some more accuracy out of them.

I'd love to know more about your .223 experience. I've got a 14" T/C barrel in .223 that will eventually become a project..... Right after I straighten out my 6.5 TCU loads for all that silhouette shooting I never do :lol:
 
Nov 2009
53
0
Bothell, WA
Hmmm.... You should be able to replicate WWB accuracy pretty easily. The whole thing is related to barrel harmonics and it sounds like WWB is pretty close. Should be able to get some idea of what powder (or analog) and weight Winchester is using for a starting spot. I've seen this kind of information around, but can't remember where. Google is your friend. I've got a Springfield Range Officer (lower end Springer 1911) that went from 6" groups to less than 1.25" groups at 25 yards from a ransom rest in less than a half grain of powder. Hit the right harmonic on a really low power load and the groups tightened right up. Really fun to do that. Makes an average shooter into a little bit better than average when you get the ammo right.

Geez, this 223 thing is an experience. This thread is about case prep. With a 45 ACP, case prep is checking to see if it isn't cracked and cleaning. Now I have to learn about things like bumping the shoulder for headspace, and trimming to length. Life used to be so simple. To change over for a pistol caliber on my Dillon 650, you can generally get it done for a couple of hundred bucks. I'm somewhere north of $500 on this 223 thing right now. Granted, much of that is self imposed, but I'm lazy. Things like a power case trimmer, dedicated competition uniflow powder measure (w/case activator) and Redding competition seating dies tend to run the cost up more than a bit and gets me away from the bench as much as possible. Out of all of this, I'm worried about the Uniflow. I'm planning on loading Varget, which being a stick powder won't meter well in a Dillon powder measure but apparently will in a Uniflow; however, it might give me some bridging issues. We'll see. If we need to change, or fix something, it will get done. I'm really enjoying the journey, just hating the expense.
 
May 2011
288
0
NW Quadrant WA State
I'm planning on loading Varget, which being a stick powder won't meter well in a Dillon powder measure but apparently will in a Uniflow; however, it might give me some bridging issues. We'll see. If we need to change, or fix something, it will get done. I'm really enjoying the journey, just hating the expense.

The issue with Varget isn't bridging and there are NO powder measures that dispense Varget with any level of consistency and accuracy. About the best of any, even the so called "Bench Rest Quality" measures don't do well with varget due to the size of the granules. It's an extruded powder with a high density. It only takes one or two granules to vary the weight significantly. There have been numerous tests on various "Precision Shooting" forums and even the highly rated Harrell Powder measure doesn't do well with Varget.

I load Varget on my Dillon 650 and get +/- .2 grain spreads using the Dillon powder measure. For my "Match Grade" .308 ammo, loaded on my 650 I just replace the powder measure with a Lee Rifle Powder die and put a funnel in it. All charges are then dispensed from a RCBS Chargemaster which doesn't vary more than the "round off factor" for a given charge. If a charge is .06 gr more than the desired charge it then shows a .1 grain higher amount and you can "adjust" if you wish. In short, this means all my loads have powder weights within +/- .05 gr. Just pour the powder in the case while the handle is down and don't get distracted. This method allows me to load 100 rounds per hour but could be at least doubled if I got a second Chargemaster.

Just a question. Why Varget in .223? More common powders are AA2230, H-335, or BL-C(2) which were designed for the round. Those powders meter real well through just about every powder measure.
 
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Nov 2009
53
0
Bothell, WA
Varget is acually a pretty common powder used by service rifle shooters. I'm using in on recommendation from a pretty good shooter. The load he gave me was kind of funny: 24 gr. Varget, any bullet. For service rifle 24 gr. Varget and a 69 gr. Matchking is kind of a goto load out to 300 yds. or so. At 600 yards 78 gr. bullets come out to play. Given the accuracy potential of the platform and the accuracy needs of the sport, I understand the load advice. At first blush, it's ridiculous because you might get into dangerous pressure variations if you don't adjust powder charge with bullet weight. But, think this through a bit. Go to load is 24 gr. with 69 gr bullet with an OAL to fit into a magazine. Lighten the bullet, more room in the case at same OAL, lower pressure - still GTG. When you go over 69 gr. you are not setting OAL for the magazine now, you're setting it on chamber length. Bullet's too long now and you would be taking up way too much case volume setting to mag length - bad for pressure. But knowing that you're using the heavier bullet for long range shooting, slow fire, single round at a time with a need for good accuracy, you set it for about .010" or so jump to the lands. Leaves more room in the case and you wind up keeping your pressure under control. Accuracy available in the platform may not make load development to the 0.1 grain, 0.5 grain, or even 1 gr. accuracy necessary.

If I don't like it. I'll move to something else and start again. That's why this is so much fun.
 
May 2011
288
0
NW Quadrant WA State
You'll also find a lot of Service Rifle shooters using RL-15. It's similar to Varget in performance but sure meters better in a powder measure.

Ditto for N135 and N140 but the Finnish powders are often harder to find on the shelf.

As the the One Load for All Bullets, all he gave you was a light load for the light bullet and a "right load" for the heavy bullet. Take these "recipes" that other competitors hand out with a grain of salt. Remember, they are supposedly good loads for THEIR rifles. May be a real bad load for YOUR rifle.
 
Nov 2009
53
0
Bothell, WA
You'll also find a lot of Service Rifle shooters using RL-15. It's similar to Varget in performance but sure meters better in a powder measure.

Ditto for N135 and N140 but the Finnish powders are often harder to find on the shelf.

As the the One Load for All Bullets, all he gave you was a light load for the light bullet and a "right load" for the heavy bullet. Take these "recipes" that other competitors hand out with a grain of salt. Remember, they are supposedly good loads for THEIR rifles. May be a real bad load for YOUR rifle.

Yes. All true. I've got to start somewhere and this is where I'm at. I know adjustments will come. I also need to learn to shoot before I worry about optimal ammunition preformance. As I get to be a better shooter, I will work much harder on developing good ammunition. Right now, if I can get to the range with reliable ammunition that will hold a 10 ring, I will be happy. The trigger guy needs to get some practice before worrying about squeezing the last little bit from the gun.
 
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