Possible overpressure in 357 mag

[Sam Sackett]

I was recently at the range. A guy at the other end of the firing line was shooting and I noticed his report was quite loud. As he was leaving, he walked by me. I stopped him and I asked what he was shooting. He said it was a S&W snubbie. I asked what was the ammo. He said it was his hand loads, which were 6 grains of Bullseye behind a 148 wadcutter crimped in the crimp groove.

Please, someone give me some guidance. That sounds to me like an overpressure load. Can someone run that in Quickload and let me know?

Sam Sackett

[megasupermagnum]

My computer with QL has a broken screen right now, but that load doesn't look out of line to me. It's hard to say exactly how deep his bullet was, but with 158gr bullets there's all kinds of data up 7-7.5 grain range.

[ddixie884]

Lyman 45th gives 4.5 as max. That seems a little warm with a wadcutter with the reduced case capacity. Bullseye scares me half to death that is why after reading for a coupla years and finally buying a press I loaded only with Unique for a coupla more years and my second powder was 2400......

Ya pays yo money and ya takes yo chances.............

[Hannibal]

Don't have my books handy so I've not checked the data, but the report might have been loud because it was a snubbie.

Could be the cylinder gap was getting a bit wide, too.

Lots of possible explanations.

[Randy Bohannon]

Bullseye is a wonderful powder when used within its parameters maybe the among the useful powders for cast lead bullets in the 45 ACP . No powder has been developed that is 100% non fouling and moron proof.

[Silvercreek Farmer]

Doesn’t seem outside the realm of reality, certainly near max 357 pressures if not over but it all depends on his actual seating depth and nose profile (ie button nose) which we don’t know. The chart below is for a 38 special case.

[racepres]

Do we know,, if he knows,, difference between Wadcutter and Semi Wadcutter??? Many do Not make a distinction.

[NSB]

I’ve got several loading books, and three of them are Lyman. Given the info we have, it may be safe to shoot the load given not knowing the exact bullet he was using. The real question here is this: what the heck was the guy trying to accomplish with that load? I can’t even imagine what he thought it was good for. Target shooting? Way too much. Hunting big game? Get another bullet….and a different gun for that application. Guy sounds like he doesn’t have a clue about what he’s doing. Not the OP, the guy with the gun.

[725]

There is a school of thought that some agree with and some do not, that a full speed wad cutter is a good defensive choice. Considering that many like a big meplat for hunting performance, I can understand the thought that a wad cutter would be a good choice for a defensive bullet. My only experience comes at shooting a woodchuck with a .30 wad cutter(kinda) and the results were instantaneous. As has been said, "a lot of air in and a lot of blood out". Only "The Shadow" knows what lurks in the hearts of men, and who knows what the snubbie shooter was thinking.

Had to post this twice. #1 vanished off into the ether of cyber space.

[Larry Gibson]

The lower max 4 +/- gr loads are in deference to soft swaged lead WCs. Such max loads are based on accuracy deterioration/leading, not pressure. With harder cast WCs, especially those with a crimp groove which are seated farther out, the max loads of 7 gr +/- are correct.

[Sam Sackett]

Thanks for the replies. I didn’t ask what the gun was, but I hope it was a 357. If so, looks like he was at the upper end of the load range. Either way, I don’t think I want to stand next to him at the range.

Sam Sackett

[jdgabbard]

6grs of BE sounds pretty hot to me. I typically load the H&G 50 or 358495 with just 3gr of BE. And they're more than I could ask for in the target department, which is what they're good for. Anything hotter and I'd be looking for a different boolit.

[P Flados]

According to Quickload, a seating depth of 0.510" with a 148 gr wadcutter in a 357 and 6.0 of Bullseye puts the round just over the SAAMI limit (see table below). If I decrease the seating depth to 0.490, the predicted pressure for 6.0 gr drops to 34054 psi.



Cartridge : .357 Magnum (SAAMI)
Bullet : .358, 148, LEE 358-148-WC
Seating Depth : 0.510 inch
Cartridge O.A.L. L6: 1.370 inch = 34.80 mm
Barrel Length : 6.0 inch = 152.4 mm
Powder : Alliant BULLSEYE

Predicted data by increasing and decreasing the given charge,
incremented in steps of 3.333% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-33.3 52 4.00 962 304 16294 2999 99.1 0.805
-30.0 54 4.20 997 326 17864 3138 99.6 0.770
-26.7 57 4.40 1030 349 19516 3268 99.9 0.738
-23.3 59 4.60 1063 372 21252 3388 100.0 0.709
-20.0 62 4.80 1095 394 23074 3503 100.0 0.682
-16.7 65 5.00 1126 417 24983 3618 100.0 0.658
-13.3 67 5.20 1157 440 26982 3732 100.0 0.635
-10.0 70 5.40 1186 463 29072 3846 100.0 0.614
-06.7 72 5.60 1215 485 31257 3959 100.0 0.594 ! Near Maximum !
-03.3 75 5.80 1244 508 33538 4072 100.0 0.576 ! Near Maximum !
+00.0 77 6.00 1272 531 35918 4184 100.0 0.559 !DANGEROUS LOAD-DO NOT USE!

[Charlie Horse]

357's always sound loud. Don't buy used guns from that guy.

[rintinglen]

6 grains of Bullseye is higher than any .357 magnum load for any cast wadcutter listed in any manual that I have. The old Speer manuals did list some JHP loads that were higher, but I can tell you that today Speer says not to use any data from any manual before Speer 12. Likewise, Lyman 48 showed 7.0 grains max for a 150 grain SWC, but "Boldly going where no man has gone before" may be OK for Star Trek (unless you're wearing a Red Shirt): not here.

[super6]

I will not use more than 5 grains of Bulls eye in any 357 I own. More like 4.5. And that is a hand full.

[Sam Sackett]

Thanks, everybody!
Sam Sackett

[Kosh75287]

When I load 5.0-5.3/Red Dot/158 gr. LSWC in a .38 Special case, it RELIABLY gives me just over 1000 f/s from a 2" barrel. I think QL said it develops about 26,000 psi. Red Dot burns at either 94% or 96% the rate of Bullseye. Additionally, there is likely a lot more air space in a case topped with 158 gr. LSWC, crimped behind the driving band (in the crimp groove) than in a case with a flush-mounted 148 gr. HBWC or DEWC. If he's loading 6.0/Bullseye under a flush-mounted 148 gr. WC, he could be developing half-again to twice the pressure that MY load creates.


Don't buy used guns from that guy. Sound medical advice.

[GLynn41]

in the 70's when i started reloading-- my rule was do not use a powder that can be double charged-- for me it is still a good rule

[imashooter2]

The 2000 Alliant free manual says 5.7 grains is max. With the neutering of .357 pressures in modern manuals, he might well have found 6 listed in an older book.

[racepres]

The 2000 Alliant free manual says 5.7 grains is max. With the neutering of .357 pressures in modern manuals, he might well have found 6 listed in an older book.
Easy to find data for over 6 grains of Bullseye, for heavier SWC...even data from the '90's!!! Not, However for Wadcutters... all I have ever found stops at 5.7 with Wadcutters...
Some Loaders do Not bother to consider case volume...only Bullet Weight...