trim 9mm range brass for accuracy?

[Jayhawkhuntclub]

When I say accuracy, I'm talking shooting from sandbags. Not just knocking down some steel. What do you think?

[MT Gianni]

How much does your vary? I sort by mfg and call it good for the 9.

[Love Life]

I trim all pistol brass to a uniform length.

[Shiloh]

I tried with 38 and .357 years ago. A lot of work for negligable results. I'd never do it again. 9mm is absolutely out of the question. Stick to the same brand. Try trimming some and report back.

Shiloh

[tazman]

I am not a good enough shot, even off sandbags, to see any benefit from trimming brass for any other reason than function. If it goes into the pistol and fires, it is good.

[dtknowles]

I don't trim, I hate brass prep if I am out for best accuracy and I am crimping then I sort brass by length. I always load in batches of a single headstamp. So sort by headstamp, number of reloads and if really picky case length. For 9mm I mostly use WIN brass and never have trimmed or sorted for case length. I have some lots of ammo I used nickel plated brass with other headstamps but that is for "special" ammo. Pretty much the same story for .357 Mag. WIN brass for most and Nickel for "special" ammo, no trimming, sorting by length is during bullet seating, I can tell by feel of a case is long as it will hit the crimp earlier in the stroke if I am using a single stage press, that round will get set aside, if the case was short it will show up in visual inspection and get set aside as well, if I can't feel it is long and I can't see it was short then it will shoot with a high degree of accuracy. If I am loading full power .357 loads, I measure charges and use the single stage press. Mid range .357 loads on the progressive still shoot quite accurately but there is no feel to loading on the progressive except when something is really wrong.

Tim

[GooseGestapo]

Don't bother.
I shoot several S&W PPC-9's (4509PC; 5,6" "Limited")
Sort brass by head-stamp. Use Starline, Winchester, or Federal sorted by headstamp for accuracy. Anything else is a **** shoot in more than one sense of the word.

I've got some P-D (Starline for Precision Delta) brass that's been loaded over 50 times with no measurable stretch or change in accuracy. I use the Lee 105gr SWC over 5.2gr of LongShot and get sub-2" groups from sandbags at 50yds....

[dudel]

Not sure case length has as much impact on taper crimp rounds as it does on roll crimp rounds.

[gray wolf]

When I say accuracy, I'm talking shooting from sandbags. Not just knocking down some steel. What do you think?
Don't take this personally, but if you were sitting on a stool in my cabin this is what I would ask anyone that asked the question.
Accuracy ? What are you looking to achieve ?
How good of a shot are you ?
Putting a sand bag or two on a bench doesn't necessarily mean your shooting off sand bags. ( technique )
What distance are we shooting at ?
What pistol ?
How good is the trigger ?
How good are the sights ?
How good are your RE-loads shooting now ?
Have you tested more than 3 or 4 loads ?
how about powder ? tested more than one ?
At that point someone may ask, or say, hey man I asked a simple question, why the third degree?
Why ? cause trimming a pistol case is about the last thing that will improve your accuracy ?

What it will do is give an even crimp to all the bullets and about .00001% better ignition for a 9Mill that head spaces off the case mouth. That is if your brass is all the same.
A lot would depend on just how good you were shooting now, What do your targets look like at this point ? and how good is your pistol (how good can it shoot ? )
The targets below were shot with all mixed brass, primer pockets were not cleaned or altered,
Some brass was trimmed some was not. Another words most of the effort was on the shooter and technique, and very little on case prep, powder was dispensed to .1 accuracy.
I don't think .003 or .004 difference in case length would tighten up these groups.

Short answer NO you won't see the difference But try it and let us know how it works out.

[Ed_Shot]

I use only range pick-up brass for 9MM and probably have 20K. I sort by head stamp but I do have an "OTHER/MIXED" category for the small quantity of some brands I have. The only 9MM I don't reload are S&B and CBC because of neck tension problems...for me at least. My issue with 9MM brass is the short stuff because it doesn't get expanded adequately by my M Die and leads to shaved boolits. After it's cleaned, sized and sorted I measure each case (ok...my time and my hobby) and discard any 9MM case that is shorter than .747. WIN brass is the biggest short brass offender. I used to trim all 9MM brass longer than .751 but I got to where I enjoyed all that I could stand. Anyway, my M-die is set to adequately expand brass that is .747 and the longer brass just gets a little bigger bell.

[bobthenailer]

Since range brass is so avaliable for the 9mm, i have never bought any.
What i do is sort by name brand and each different brand is used for a different load combo .
I personaly never mix brands of brass in a given load as accuracy is less as well as higher velocity spreads . i only use Federal , R&P and WW 9mm brass , almost all other brands go to the scrap bucket to be recycled

[osteodoc08]

The real reason for trimming brass, IMHO, is for a consistent taper crimp. I've measured tons of 45 acp brass and most are within a few thousandths of each other and means nothing for me in a practical aspect. I load and shoot. Trim length would be the LAST place id look for accuracy improvement. Youre better off spending that time on the range.

[knobster]

I never really noticed that pistol brass was different lengths until I started using my Lyman M die. I then began to notice that some of the brass cases didn't flare as much (some barely at all) while running them through the die. Contemplated trimming them all but since I have 4-5K cases sitting on my shelves I'll probably just sort by head stamp. So much to do...

[MT Gianni]

For an easy test take 25 cartridges of any head stamp other than American Merc. Pick a brand you have little confidence in. Sort by weight culling to 1.5 gr of norm, don't clean primer pockets or uniform flash holes. Trim 12 of them leave the others as is. Pick mixed head stamped brass and load 12 untrimmed but with clean primer pockets, and uniformed flash holes if you have the right size bit. Load 12 mixed, prepped and trimmed to length. Shoot the same loads, call your fliers. I predict the best loads will be same head stamp and weight sorted with the trimmed being the winners by a small fractional amount. Next will come the mixed cases prepped and then the mixed overall. The differences will surprise you, and now you have to keep your brass sorted.

[gray wolf]

For an easy test take 25 cartridges of any head stamp other than American Merc. Pick a brand you have little confidence in. Sort by weight culling to 1.5 gr of norm, don't clean primer pockets or uniform flash holes. Trim 12 of them leave the others as is. Pick mixed head stamped brass and load 12 untrimmed but with clean primer pockets, and uniformed flash holes if you have the right size bit. Load 12 mixed, prepped and trimmed to length. Shoot the same loads, call your fliers. I predict the best loads will be same head stamp and weight sorted with the trimmed being the winners by a small fractional amount. Next will come the mixed cases prepped and then the mixed overall. The differences will surprise you, and now you have to keep your brass sorted.
I have the utmost respect for the man that posted the above post. Saying that, I have a hard time disagreeing with his advise, So let me please say that I kinda disagree.
If I were shooting rifle, and I do,-- my case prep is very extensive and I do see a difference in how my rifles shoot. Seems the more work put into case prep, the better the outcome. So for a rifle off a bench for max accuracy I agree.
But for a handgun, I have not seen the the outcome for the effort, + the OP was talking about just trimming the brass.

[MaryB]

I trim range pickups just to make sure I start with stuff that is all the same length. Once trimmed I check it now and then but have yet to retrim. Also gives me a very good time to check each unknown range pickup over for defects. I sit and watch TV and trim, kills time in winter.

[oldfart1956]

I trim range pickups just to make sure I start with stuff that is all the same length. Once trimmed I check it now and then but have yet to retrim. Also gives me a very good time to check each unknown range pickup over for defects. I sit and watch TV and trim, kills time in winter. What she said. I buy in bulk...sometimes 2K at a time. It's all mixed up though Federal and Blazer seems to make up the bulk of it. I go through every piece, check for flaws/damage and to see if anyone fiddled with it. Most of it is 1 time fired (local indoor range) but now and agin I find one with a primer overflowing into the headstamp. I chuck that one. I tumble, de-prime/size and check/clean primer pockets, trim to length and knock the sharp edges off the mouth and run a finger around the edge to see if it got gammahooched with the extractor. I'm not saying it actually improves accuracy (especially with me shooting) but I need to know all the hours I spent casting/sizing/lubing those boolits and carefully dropping powder charges aren't a waste. It certainly can't hurt the accuracy and powder&primers are too dear to waste. Just my take on it. Audie...the Oldfart..

[MT Gianni]

I read a tip from Jim Taylor years ago. My Rem 9mm weigh 3-5 gr heavier than Fed which are 4 gr more than Win. PMC's are different from any of the others. I find that most of my 9 brass does not grow when fired. 223 otoh acts like a 12 yr old kid and needs trimming every other firing.

[Garyshome]

I have too many to mess with that part of case prep.

[Recluse]

I've never considered 9mm or 9mm firearms accurate enough to mess with refining accuracy for my reloads all that much. From the Berettas to the HK to the Browning Hi-Power, they all shoot close to the same with the nod in consistent accuracy going to the P7, but not by much. I primarily load jacketed projectiles in most of my 9mm reloads and so long as I can score a 295 or better, out of a notional 300, on my old USMS qualifying runs, then I'm happy.

Trim 9mm brass? I don't even sort it by headstamp.

:coffee:

[Whitespider]

I don't have a 9... but I do have a Firestar in .40 caliber. It ain't built for shooting bottle caps at 50 yards, it's built to deliver lethal impacts in defensive situations... it shoots something close to 2½-3 inches at 25 yards. I've experimented with sorting head stamps, trimming to consistent length, weighing cases, cleaning/uniforming primer pockets, etc... it still shoots something close to 2½-3 inches at 25 yards. I don't bother with any of it... I just load mixed cases and straighten the flare out with a taper crimp die. If your 9 ain't capable of reasonable target accuracy (like something under 2 inches) I wouldn't bother... it ain't possible to make a silk purse from a sow's ear.

But I do trim (most) revolver cases... according to my chronograph a consistent roll crimp does make a difference in shot-to-shot velocity variance. I only trim them once, after they've been fired a couple times, and I've never noticed they "stretch" after that trimming.