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Surfersami
02-10-2019, 09:00 PM
Hi All,
This may be in the wrong place, I am new here and looking for some possible help on a load that I have.
The back story:
My Grandfather was a police officer in the Panama Canal Zone. I inherited his S&W M28-2 6" Highway Patrolman. Along with it I received some factory 38 special and 357 magnum ammo. I also received some hand-loaded 357 Mag bullets. They seem to shoot a little hot, but I don't have a chronograph to test them. Here is what is written on the box:
155 gr alloy w/gas check (Kieth style bullet but no clue what that actual alloy is). 14.5 gr H-240, Magnum primer, nickle shell case.
These were loaded by my great uncle. Grandpa told me he was a ballistic engineer for the army. He had been tasked with creating a round for sentries that would disable a vehicle. This load, is what he told grandpa, is what he presented to the army. He had told my grandpa to only shoot it out of his N-frame revolver.
Here is what I have observed:
The report is quite loud and the blast is substantial. It is extremely accurate out of my M28-2. Fired at an 8" oak tree that was to be cut down on my property the round went completely through the center of the tree and was not recovered. Fired at an old inline six truck engine, the bullet broke the outer case but did not penetrate further. The round seems to burn pretty clean and with the gas check there is no detectable fouling in the barrel. Cases do not show any of the typical signs of over pressure, easy to extract, no bulging of the primer etc.
I have no access to loading manuals that have the H-240 powder in it, so I have no idea of what the velocities may be, or what the pressures would be. Any help with what these loads might be doing would be greatly appreciated.

dragon813gt
02-10-2019, 10:10 PM
Here’s an old thread about the powder: http://castboolits.gunloads.com/showthread.php?76871-H-240-powder&

Surfersami
02-11-2019, 04:55 PM
Thanks for the reply, maybe I need to find a chrono and shoot some more. I am wanting to start reloading for this 28-2, I have saved all the brass I have fired in the past. this has sparked my interest again.