trimming problems 357 mag

[Shadow9mm]

so I have a redding 2400 match precision trimmer. I have had issues with it several times with the casings binding on the pilots of 223, 308, 30-06 and now 357 mag. the problem is it is binding to the point where it is hard to turn and it is enough the break loose from the set screw and lose my length setting.

I am using mixed once fired brass and have had problems with lengths being inconsistent and being able to properly line the crimp groove up.

So I started with 357. federal cases trim fine. Every other brand is binding on pilot due to brass shaving buildup. I am trying to find a solution so I can process this brass.

I though maybe there was a burr in the case mouth from the crimps. I deburred the case mouths, same problem.

I just tried doing light case mouth flare prior to trimming. it helped, but only on about 50% of the casings. they slid over the pilot easily. but again began binding up after the first couple turns.

Should the pilot be a tight fit to keep shavings out. should be a looser fit to let shavings pass. is it an issue with sizing the body and some brass is thicker making the inside smaller on the pilot. how tight does the pilot need to be to properly square the case over the cutter?

the pilot measures .0354

I'm struggling here...

 

[44 AMP]

You might consider a dry lubricant (like graphite) and a small brush to sweep away the shavings.

I've never trimmed flared cases,

Alternately you could check the diameter of your pilot against the inside diameter of your brass, and possibly have the pilot turned down a tiny bit.

Also, there's no reason I can think of why you can't trim fired brass before sizing, PROVIDED you do some checking and know how much to trim to compensate for any growth during the sizing process.

The point of trimming a case like the .357 isn't to get an exact specific length (any length below max can work fine), the point is to make all the cases a uniform length, so that once the die is adjusted, your crimp will be in the right place, and the right amount for all your brass.

A few thousandths above or below the recommended trim to length won't matter any, as long as all the brass is the same length.

 

[Shadow9mm]

I was always told, generally, handgun cases don't grow much, only bottlenecked rifle due to the way they push the brass up when resized.

I decided to try flared to see if the little extra space helped. It was a little better, but not a lot.

I may try trimming before sizing next time. consistency in length for lining up the crimp groove is, like you said, my goal. but I have 250pcs to get trimmed and fired before I can try that...

I had length varying from 1.278, to 1.292... with it being mixed brass I want to trim it all to get it consistentand and hopefully it will stay that way.

 

[RC20]

I don't think it makes any difference, shoot as is.

 

[NoSecondBest]

I’ve shot .357mag by the countless thousands for almost fifty years. I’ve never trimmed any of it and never found a need to. It shoots very good untrimmed. It just doesn’t grow from shooting and even very minor case length differences still fit in the crimp groove.

 

[Steve in PA]

30+ years of reloading both rifle and pistol. In all those years, I’ve never trimmed a single piece of pistol brass.

 

[zplinker]

It is very easy to show the inconsistencies that result from pistol brass of different lengths, mainly those requiring a fairly heavy roll crimp. I've trimmed thousands of .357 and .44 Mag brass, after sizing, and the resulting crimp is very precise. And so are the velocities, when chronographed. A Wilson trimmer will solve the pilot problem, as it works like a lathe, and no pilot. Most shooters may say that consistent velocity isn't that critical at the ranges handguns are fired at, but try longer steel targets, 200-300 yds., and it is a whole different ball game.

 

[NoSecondBest]

I don’t know anyone shooting steel at 300 yards with a .357mag, but I suppose there’s some that do. I do know that I shot IHMSA silhouette for many years and I’ve owned four custom built .357mag handguns that were real tack drivers…..two Bill Davis revolvers and two Coonan custom built semi-autos. All were superbly accurate guns and somehow I managed to qualify as AAA my first time out at IHMSA silhouette standing shooting a TC Contender in .357mag. My first score was a 25x40 shooting out to 200 meters. Both Davis guns would shoot ten shots into 1” at fifty yards. One was a SW 27 extensively modified and the other was a Ruger Security Six also extensively modified. It would shoot just as well. None of the brass I shot in .357 was trimmed. Not one single piece. I’m shooting brass today that I bought in the 1980’s (bought in 1,000 piece lots a several of times) and it still shoots great. I’ll stand by my remarks that it doesn’t need to be trimmed and it would be a rare individual indeed who could measure any difference in accuracy at any distance.

 

[44 AMP]

I won't dispute the fact that you don't need to trim to a uniform length for accuracy. I still have brass I got in the 70s, and its never been trimmed.

I do think they should be checked for length, and seriously short or long cases separated out. Often in you buy in large lots, new brass things are pretty consistent and stay that way. But if your case stash is range pick up, or gun show bulk you might have 16 boxes of brass with 12 different headstamps and lengths can vary considerably. Those need to be checked, separated into batches and possibly trimmed for uniformity, not for accuracy but so you don't get under or over crimped rounds when loading them.