To Case trim or not

[AZ Pete]

There is no reason to trim straight wall pistol brass, at least I haven't found one in the last 55 or so years of loading them.

[1hole]

Saying the Lee Trimmer is getting .888" may not be true, depending on how it's being measured.

Critical machinists consider most hobbyist grade micrometers and dial calipers (like ours) to only be accurate within +/- one mark and being one thou off has little significance in our reloading bench work, perhaps especially so for case length.

[EDG]

Just measure your chamber lengths. Make your brass work in the shortest chamber.

[d4xycrq]

The only pistol brass I’ve had to trim is rifle brass. 30 Carbine. Is 30 Carbine a PCC caliber?!

[Randy Bohannon]

Since 45ACP uses a taper crimp case length becomes slightly less important other than not to long. Like others I have never measured a 45ACP case that was to long or trimmed one. Some guns get their brass match grade or improved either by flash holes uniformed ( most important IMO) or length trimmed, 44-40 WCF benefits a bunch being uniform length as any thin necked brass and a roll crimp.

[mike4045]

I have been reloading 40 years plus, a majority of it has been pistol, and I have never case trimmed any pistol cases. Had numerous 45 acp cases with 20+ loadings and never needed trimming.

[tankgunner59]

I use my Lee trimmers to check the length before first loading, after that I have not needed to trim my straight wall pistol brass. Most of my trimming is for bottle neck rifle brass and any brass that takes a roll crimp.

[Conditor22]

I check brass that has a crimp groove like 38 spcl, 357, 44mag, ...

I'm currently trying to get Hornady to replace 71 pieces of once fired 357 brass that is .005 under SAAMI

[JoeJames]

I have never trimmed pistol brass, and have been reloading 38 years or so. It has all been straight wall and moderate loads at that: 32 S&W Long, 38 Special, 44 Special, and 44 Magnum (at around 1050 fps). I have trimmed a slew of 308 and 556 brass to get them down to at least maximum spec.

[Three44s]

I find .223 and 5.56 cases are all over the place for length.

I ran a lot of my unprocessed brass of that persuasion the two previous summers and encountered stuff from 1.778” down to 1.738” after lube and full length sizing.

Max is 1.760 and Trim to is 1.750”.

I chose 1.747”. If it was much shorter, I segregated it out.

Up on first firing in my bolt guns the treated brass settled down to 1.751” of so.

I figure that I have bought myself quite a few firings before I will need to trim again because I use the Lee Collet neck sizer for the bolt guns.

Three44s

[JoeJames]

I find .223 and 5.56 cases are all over the place for length.

I ran a lot of my unprocessed brass of that persuasion the two previous summers and encountered stuff from 1.778” down to 1.738” after lube and full length sizing.

Max is 1.760 and Trim to is 1.750”.

I chose 1.747”. If it was much shorter, I segregated it out.

Up on first firing in my bolt guns the treated brass settled down to 1.751” of so.

I figure that I have bought myself quite a few firings before I will need to trim again because I use the Lee Collet neck sizer for the bolt guns.

Three44s

I think the max I encountered was 1,781" or so. Quite a lot of it too.

[Three44s]

JoeJames,

I only had a scant few at the very upper end but more just over 1.770”. I will take my Lyman Universal with a carbide cutter to those extra long cases and finnish with a Wilson trimmer. In between runs I inside and outside debur to reduce cutter drag.

Three44s

[blackthorn]

Case length (to me) does not matter, unless they are enough over-length to cause dangerous pressure problems. The way to know is to do a chamber cast and determine where the end of the chamber/throat is. As long as cases remain below that you are good to go. That said, there are instances where cases of equal length are needed.