357 load in 38 cases

[PotatoJudge]

I recently (accidentally) put a couple of 38 cases through the press while loading 357. The case of course is uncrimped and the OAL is the same as all the 357 loads. My question is, since the internal volume for combustion is the same in both cases will pressures be increased in the 38 case? I understand the danger of shooting these in a 38, but how about an L frame or 357 Max Contender? The load is 15.5 grains (max is 16.2) of Vectan SP3, WSP, and a Speer 160 grain half jacket SWC.

I understand why 357 load data used in 38 cases with 38 OAL is unsafe, but what if the OAL of the 357 is used?

 

[ArchAngelCD]

It's my understanding .38 Special brass is not as heavy as .357 Magnum brass.

Why not error on the safe side and pull the bullets from the .38 Special cases especially since there are only a few. Always error on the safe side, there's no reason to take chances with your health.

 

[PotatoJudge]

I've heard that 357 cases are thicker, but haven't measured to verify and don't know if it's a safety concern with a single medium range 357 load. I'm not set up to trim 357 cases here, but I wonder if one trimmed a 357 case down to 38 spl length how it'd compare weight-wise with 38 spl, 38+p, and 38 +P+ cases.

I'm still curious about the actual safety of the loads.

 

[evan price]

Sinc we're only talking a couple of cases here, I am going to say disgression is the better part of valour: Pull 'em down and fix 'em.

 

[ArchAngelCD]

BTW, .38 Special and .38 Special +P brass cases are exactly the same except for the +P marking. As far as I know there are no .38 Special +P+ cases since there is no SAAMI standard for +P+.

Like I said in my first post, just pull the bullets on the .38 Special cases and call it good...

 

[JDGray]

Shoot them, and report back. Brass has no strength anyhow, and the case is 100% supported in a revolver- TC. The only reason 357 cases are longer is so they wont chamber in a 38.

 

[easyrider604]

I understand why 357 load data used in 38 cases with 38 OAL is unsafe, but what if the OAL of the 357 is used?

Following the logic, it would seem that the answer to your question is yes, pressures would be similar if you kept overall length equal.

The difference may be the 38 spl loaded with the shallow bullet seat depth may have erratic pressure due to less bullet to casewall friction. A heavier crimp may help but it may be interesting to do some chrono readings to see how consistent velocities will be.

 

[mkl]

You are safe as long as you keep them out of a 38 Special revolver.

 

[Wiljen]

I weighed several 38 special cases tonight just to get an idea of the differences in them. These are all nickel cases - once fired without primers.

Headstamp Weight (Avg of 20)
FC 88 65.3gr
Federal 38 Special 65.7gr
Federal 38 SPL +P 65.1gr
FC 38 SPL +P+ 65.7gr

R-P 38 SPL 63.4gr
R-P 38 SPL +P 64.7gr

(AVG of 5)
R-P 357 Mag trimmed to 38 length 65.9gr
FC 357 Mag trimmed to 38 length 66.2gr

From a rough sample it would appear that the only difference among 38, +P, and +P+ is the headstamp on the case. It also appears that 357 Magnum brass is not significantly stronger than 38 brass based on weight comparisons.

 

[PotatoJudge]

Wiljen, thanks for doing the legwork on this one. Looks like 357 cases aren't any "heavier."

I'm thinking these loads are safe and, while I don't have plans to do this sort of thing on purpose, should be safe in my 357s. I'll let you guys know if I lose any fingers over this.

Easyrider, I may save the loads until I get a chronograph (got a birthday coming up soon) and see if they perform any different. Unfortunately, a sample size of 2 is pretty weak and I don't have plans to load more.

 

[joneb]

When resizing .38spl vs .357 Mag. brass I notice the difference, as for why I'm not sure. Alloy or maybe wall thickness ? The Mag. brass is noticeably harder to resize.

 

[Clark]

38 special registered with SAAMI for max average pressure of 17,000 psi.
38 special brass will have long life with max average pressure of 80,000 psi.

270 Win registered with SAAMI for max average pressure of 65,000 psi.
270 Win brass will have long life with max average pressure of 62,000 psi.

What gives?
The 270 rifles are built better than the 38 special revolvers.