Forums.NitroExpress.com

There are many variables.
The curve is not the problem in most cases. The problem is over pressure or excessively fast pressure rise. Over pressure is serious but generally not catastrophic unless in a weak action like a the toggle link Winchester design or a vintage barrel/cylinder.
I know that it is virtually impossible to blow a 45-3 1/4" American made Sharps copy with 500 gr jacketed bullets and all the IMR 4198 that will fit. It will not even stick the cases according to the tester.
I also know that a reduced charge, 50 grains or so, of 3031 is very dangerous with a lead bullet in this cartridge (hang fires and smoke from the breech before the powder finally fully lights) and will blow a 50 3 1/4" to fragments. My warnings did not "take" and he tried 3031 anyway and *really* broke the rifle. I could not "control" his ignorance. Had he used 90-100 grains he and the rifle would have likely been unhurt, well the gun anyway. He might have learned a lesson in recoil.
I know that, at least in the old Winchester I had, 7gr of Unique in a 38-40 produces large variations in velocity. The warning sign of an impending "event". Magnum primers cured this.
I know that 6.5 gr of Red Dot is OK with a 250 gr in 45 Colt but using a 200 gr will likely blow up the revolver. 13 grains will not stick a case so it was not a double load.

I am confidant that a full case of Bullseye will not burst a 357 mag revolver, at least a good quality one, but a light load of +- 3 gr. will break it. Its been proven repeatedly.
This reduced charge "phenomenon" is not limited to small arms but will blow up field pieces as well.

A friend and the lab owner once fired a box of *factory* 38 Specials through a pressure gun. By tipping the cartridges at different angles to "index" the powder before loading they achieved pressures from 16000 (normal) to 32000 (proof level or more) all from the same box of ammo.

This and some blown guns I have examined makes me very uneasy about reduced loads of smokeless. I am also very uneasy about smokeless is traditional MLs due to soft ignition and usually POOR BARREL STEEL. Percussion revolvers have a better ignition path and might be safer.

Your cylinder adaption gets around one worry, poor ignition and is a elegant work around. Setting it up to hold just the proper charge is also a plus.

I have a friend who found a relic on his ranch years ago. Someone had apparently pulled apart some revolver ammo to load a 1858 Remington. He found the gun parts, most of them anyway and searching produced evidence of the ammo being disassembled. This was done long before he found it. But a vintage Remington is not in the same class as a modern reproduction *if* they use suitable steels.

Dan