The Firing Line Forums - View Single Post - shooting black powder cartridge loads in modern guns.

B.L.E. · February 18, 2011, 08:05 PM

Black powder works great in .38 special/.357 magnum ammo. You can not possibly put enough black powder in a .357 magnum case to come even close to blowing up a modern gun.
Black powder should be slightly compressed in the case, no air space. You can determine the load by putting some powder in a unresized empty case and seeing how far you can push the bullet in before it compresses the powder. When you have enough powder so that you have to compress the powder a sixteenth of an inch or so in order to seat the bullet, that should be a good starting point for your powder charge.
I suggest using fffg but ffg will work if that's what you have on hand.

The bad news is that black powder is really dirty and the fouling is corrosive, the gun must be cleaned after you are through shooting, in fact, you may have to wipe the bore between every or every other cylinder of bullets.
The good news is that black powder fouling practically rinses off with good old water and the patches come out clean and white after only a couple of patches.

I think the .38 special was originally loaded with black powder when it was invented and thus the size of the case is just about right for black powder to duplicate standard .38 special velocities with a slightly compressed load.

February 18, 2011, 08:05 PM	#10
B.L.E. Senior Member Join Date: December 20, 2008 Location: Somewhere on the Southern shore of Lake Travis, TX Posts: 2,603	Black powder works great in .38 special/.357 magnum ammo. You can not possibly put enough black powder in a .357 magnum case to come even close to blowing up a modern gun. Black powder should be slightly compressed in the case, no air space. You can determine the load by putting some powder in a unresized empty case and seeing how far you can push the bullet in before it compresses the powder. When you have enough powder so that you have to compress the powder a sixteenth of an inch or so in order to seat the bullet, that should be a good starting point for your powder charge. I suggest using fffg but ffg will work if that's what you have on hand. The bad news is that black powder is really dirty and the fouling is corrosive, the gun must be cleaned after you are through shooting, in fact, you may have to wipe the bore between every or every other cylinder of bullets. The good news is that black powder fouling practically rinses off with good old water and the patches come out clean and white after only a couple of patches. I think the .38 special was originally loaded with black powder when it was invented and thus the size of the case is just about right for black powder to duplicate standard .38 special velocities with a slightly compressed load.