Trimming Cracked Case Mouth on 357MAG

[jonp]

I was wondering about how far I could trim the case down on a piece of 357Mag brass that I have. I know the min specs in the book but could I trim it shorter and seat a 148gr lwc out farther to make up for it? I'm running target loads of this only with 3.5gr Promo.

How far down has someone tried this? I'm shooting these out of a Ruger BH

[Uncle Jimbo]

For a short time a long time ago, I was trimming 357 down to 38 spl and using them that way. If the crack went down further than the length of a 38 I would just discard them. But unless you have a power trimmer, it is a lot of work and in my opinion not worth it, that is why I stop doing it.

[w5pv]

I seat them as if the brass wasn't trimed down and keep th OAL for the round the same.This for low powered rounds that I use for practice.They feed the same as a full length case so far no problems.

[scattershot]

A lot of work for a cracked case. Pitch it.

[Scharfschuetze]

A lot of work for a cracked case. Pitch it.

That and anneal the rest of your cases so that they don't crack.

[kweidner]

I would pitch it too. not worth it. I mean if I only had six cases that would be different but not worth the trouble.

[GP100man]

If ya got the time/tools , go for it ,I used to trim cases down for my cuz`s S&W28 so he could crimp 357429s in the crimp groove , I can`t remember the length now but it was more trimming than he wanted to do by hand.

lightly annealin the rest will save em from splittin, ya don`t have to discolor the brass to get it to relieve the work hardening, if you do heat it to the point of discolorin you`ll lose the cases ability to hold boolits under recoil.

[ruizhernandeztrust]

For a short time a long time ago, I was trimming 357 down to 38 spl and using them that way. If the crack went down further than the length of a 38 I would just discard them. But unless you have a power trimmer, it is a lot of work and in my opinion not worth it, that is why I stop doing it.

+1
I do the same when I'm bored, I start to trim cases, listen to the radio and drinking coffee. [smilie=1:

[xrider472]

If ya got the time/tools , go for it ,I used to trim cases down for my cuz`s S&W28 so he could crimp 357429s in the crimp groove , I can`t remember the length now but it was more trimming than he wanted to do by hand.

lightly annealin the rest will save em from splittin, ya don`t have to discolor the brass to get it to relieve the work hardening, if you do heat it to the point of discolorin you`ll lose the cases ability to hold boolits under recoil.
I believe it's about 1.20" to 1.22" trim length for the 357429

[Lonegun1894]

I have not tried this in a revolver yet, but was trying to work up mouse fart loads for my .357 Mag Contender, and in the interest of a small case and load density (I was bored and curious, ok?), I trimmed some .38Spl brass down to .380 ACP specs and loaded it with a Lee 158gr RNFP and a Lee 100gr RN. I never got it as quiet as I was hoping, and accuracy wasn't up to par either, but I didn't spend much time with my .380 ACP-Rimmed project either. Going to have to try it in a rifle and a revolver next. How's that for "short"?

[bedbugbilly]

Lonegun1894 - basically your are trimming to 39 Colt Short - I don't shoot much 357 - but I do shoot 38 Colt Short, Long and Special lengths. That's a lot of trimming to get down to a short casing - if you like that length - you'd saw a lot of work by just buying some Starline 38 Colt Short brass. I like using the Lyman 358242 121 gr RN and the Lee 358105 SWC in the Colt Short Brass - makes a nice round out of a J frame for plinking.

About the only thing I load in 357 cases is rounds for my Handi-Rifle - so far, it's new enough that I haven't had any split casings - but when I do start getting them - I'll toss 'em. On my 38 spl. casings that split - by the time I'd trim 'em back, they'd be 38 Colt Long or shorter - isn't worth the effort.For the OP's plinking load, it seems like it would be just as easy to use 38 spl, casings and seat the WC to the 357 COAL since it's a mild powder charge. But . . . if a person has the time and wants to do the trimming and annealing - I can't think of a better endeavor to keep a person occupied!

[GoodOlBoy]

I trim them down, sometimes shorter than 38 special brass. If they get tooo short then they become the next candidates for snake shot shells using speer capsules. I don't like throwing stuff away just because it's a little extra work. But then again I'm just old school that way.

GoodOlBoy

[mac266]

For a short time a long time ago, I was trimming 357 down to 38 spl and using them that way. If the crack went down further than the length of a 38 I would just discard them. But unless you have a power trimmer, it is a lot of work and in my opinion not worth it, that is why I stop doing it.

What he said.

[GP100man]

We`re scroungers , plain & simple !!!

[Lonegun1894]

Bedbugbilly, trimming them down that far isn't something I make a habit out of, but it was something I tried both to develop a new load (to me) and to see how long I could keep shooting the same handful of cases, even if it took modifying them as time went on.

[trapper9260]

I trim them down, sometimes shorter than 38 special brass. If they get tooo short then they become the next candidates for snake shot shells using speer capsules. I don't like throwing stuff away just because it's a little extra work. But then again I'm just old school that way.

GoodOlBoy

I feel the same way also,I just will reduce the load if need be and just keep load them and go from there Also do not like to have something go to waste when it can be used for some thing else of a different load.

[Mohillbilly]

Poor boy Got poor boy ways, Seat your boolits to same oal , or use a .38 special loads , or long or short Colt according to how much trimming you do . .460 can be trimmed to .454 Casull which can be trimmed to .45 Colt can be trimmed to Schofield to .45 cowboy .44 super mag to Mag to .44 Special or Russhin , .327 Fed to .32 H&R to .32 long or short . I get a new load of brass when I cut down .45 Winmag to .460 Rowland and Deutonics and could trim /load that to ACP . Besides that some have thicker/better heads when cut down to a lesser chambering , and some have smaller/ stronger primer pockets too . Cut down neck splits on a longer chamberings to a lower pressure chambering can allow you to do +p loadings in appropriate guns .