Accidentally Loaded .357 A Little Short w/H110

[GunAdmirer]

I assembled some book max .357 Magnum loads with H110 and 180 grain XTP-HP bullets. I've loaded them before and used them with great success. I roll crimped into the cannelure. When I measured the rounds (25), they were .030" shorter than the book's recommended minimum OAL. The brass is new Remington. I'm not sure how this happened. I guess I roll crimped too high in the cannelure. I know, I know. I should have measured them when I was seating the bullets. I don't load .357 very often. Because I was roll crimping into the cannelure, I didn't think they would be too short. My Ruger GP100's cylinder isn't picky on length.

I think they are probably safe to shoot in my 6" Ruger GP100. What say you???

 

[Shoney]

The easiest thing to do is rap it gently a few times in a kinetic puller, then reseat and crimp.

You did not give the load of H110 you used.

If it is close to or at max then the pressure will be higher than may be safe. If you are using a moderate load, they should be ok.

Always better safe than sorry!

 

[Steve C]

I doubt if you can seat a bullet too short using H110 as its a powder that requires high load density to burn properly.

IMO too much fuss is made of OAL. Speer manuals stated warning that high pressure can result in the 9mm with shorter OAL but they didn't specify which powder(s) they observed the phenomenon with. Now every time someone repeats this regardless of cartridge or load others act like a bobble head dolls nodding their agreement or at least acquiescence to the idea.

It should be noted that the high pressure with shorter OAL warning is found only for the 9mm and I have never seen it repeated in any other manual than the Speer.

 

[Bullet]

I believe what William C. Davis, Jr. says –

“In revolvers, the free run through the cylinder is always relatively great, and increased seating depth always increases the chamber pressures.”

GunAdmirer
I think they are probably safe to shoot in my 6" Ruger GP100. What say you???

You could try loading some more rounds (using the same reduced OAL) but work up your powder charge and see if you see any signs of high pressure.

 

[pinkymingeo]

Loading short raises pressures. If you use the same powder charge at different OALs and run them through the chrono, you'll see velocities increase as the round gets shorter. It's only 25rds. If I were you, I'd pull them.

 

[Mike Kerr]

Was the load of H110 at max ?
Slightly under Max
Slightly over max:

As a practical matter ,the seating depth situation does not sound too bad, in and of itself. However, if you were over max powder load by very much it could be a problem.

Perplexing isn't it.:banghead::banghead:

regards,

 

[Mal H]

If the crimp is indeed somewhere in the cannelure and the powder load is at or below a maximum safe load, fire away. You won't harm your GP-100.

Out of curiosity, what "book" are you using and which bullet do they use giving the OAL that you are measuring against?

 

[The Bushmaster]

I agree with Mal H...If you are within book specs for that bullet except for the OAL, but are crimped in the cannelure...Shoot'em... OAL in revolver is relative. I don't even measure my revolver or any other round that crimps in a cannelure. Waste of time...

 

[Clark]

I would shoot that load in a GP100.

All the H110 that will fit in a 357 mag with 180 gr XTP is maybe 13.5 gr, which Quickload thinks is 31,500 psi.

Change the OAL by .030" to 1.56" and @Quickload thinks you have 36,700 psi.

Because H110 has such a high bulk modulus [hard to compress] you can't get that much to fit. I would bet money you can't get enough pressure to make the cases sticky and hard to extract with H110 and 180 gr in a chamber with the steel in the chamber walls that thick.

 

[Walkalong]

Yep, If it is crimped in the cannelure you are OK. I log the O.A.L. for revolver rounds that I crimp into the cannelure, or crimp groove for lead, just because I log it for all loads. I am not looking for a certain O.A.L. with those rounds. The crimp groove determines the O.A.L..

Clark has been known to run some high pressure loads so I would listen to him.

 

[GunAdmirer]

Update

Update: I carefully shot both loads this past Saturday. The hotter (above book max 14.0 gr.) load showed only the beginning signs of pressure. The milder (book max load 13.5 gr.) showed no signs of pressure.

The hotter load is a published load but above Hodgdon's and Hornady's maximums. I had previously worked up to these loads. I was willing to take the chance because I was shooting the loads in a strong revolver and the .357 case has lots of capacity compared to a pistol round.

I will be even more careful next time to load to the recommended OAL. I believe my problem was that I assumed that if you seated the bullet to the cannelure for proper crimping, you would be at the right OAL. The XTP bullets I was using have a wide cannelure. I should have measured.

 

[Walkalong]

The hotter (above book max 14.0 gr.) load showed only the beginning signs of pressure.

I would shoot the 13.5 Gr. load and not worry about the O.A.L. so much. Worry about how much powder you are putting in the case.

.020 shorter O.A.L. in the .357 won't blow you up, but too much powder can. I realize the GP-100 is brute strong, but the brass is not. Be carefull. A few more FPS is not worth it. My 2cents.

 

[Mal H]

I agree with Walkalong. I'm not sure if it's possible to be too careful when reloading, but you might be approaching that level.

As I and a few others said, if the crimp is in the cannelure, don't get too upset if the OAL doesn't fit the book value for the OAL exactly. Pay closer attention to the load than the OAL when the crimp is in the prescribed groove - anywhere in the groove.

 

[ArchAngelCD]

I have to add my voice to being careful with the charge you are using. The old SAAMI limit for the .357 Magnum used to be 40,000 PSI. Since they lowered the limits a while back the new SAAMI limit for the .357 Magnum is 35,000 PSI. A charge of 13.5 H110 under a 180 gr bullet will give you 39,100 CUP. I don't know what that is in PSI but going from 13 gr to 13.5 gr increases the pressure from 36,800 CUP to 39,100 CUP. I'm sure 14 gr of H110 will not only exceed the new limits but bump up against the older limits too. You only get an increase of 40 fps going from 13 gr to 13.5 gr. If that translates into another 40 fps from 13.5 gr to 14 gr I really don't think that small an increase in velocity is worth possible trashing your gun or worse, hurting yourself.

If it's velocity you are looking for switch over to Lil'Gun for the heavier bullets. The Hodgdon site lists 15 gr Lil'Gun, 1422 fps @ 34,500 CUP. That's 25 more fps with pressures dropping from 39,100 CUP using H110 to 34,500 CPU using Lil'Gun. Lil'Gun leaves you a lot more room to play with without being dangerous, well, at least not as dangerous as pushing H110 any higher.

 

[Regolith]