Originally posted by Maverick
Laz,
That's correct, you must stay inside of black powder power levels. Using a smokeless powder would create a situation where it would be very easy to over pressure the load since the powder is so much less bulky. Just because the cylinder is converted to a cartridge it's still a weaker system than one designed for smokeless. I would never trust any of the imported repros with a full pressure smokeless load. I like my hands and eyes in the condition they are in and don't want to rearrange them.
I have a replica Sharps 50-70 carbine made by Garrett Arms in Virginia. The cartridge is straight walled and lofts a 517 grain bullet when loaded with smokeless powder. This rifle will also shoot black powder and a .50 cal lead ball thumb pushed into the end of the case. I prefer the smokeless loads because it doesn't foul the barrel and the ball loaded bp cartridge sometimes becomes unassembled upon extraction when unfired, leaving the ball in the barrel and a cartridge spilling powder.
I mentioned this to a Sharps dealer at the Shot Show in Dallas a few years back, and he told me I would blow up my rifle using smokeless powder. Now the shop I bought this rifle from said smokeless could be used safely, and Lyman's reloading manual does have specs for loading this cartridge with smokeless. My loads are about mid level and this heavy rifle kicks about as much as a .22 and is not much louder. Basically it is a very large .22 rifle. So I'm fairly confident it's not going to blow up, considering it is closed breach and has a falling block action which is very strong.
Black powder is a class A explosive and can detonate by percussion. If you drop your loaded bp weapon on the ground it may fire by accident so be careful. Revolvers will ring fire sometimes because of this as well. I suspect any magazine fed firearm loaded with bp cartridges could do this under the right circumstances.
I have fired smokeless buckshot shells from an old original Remington double barrel 12 gauge with the exposed hammers. That shotgun has Damascus barrels and it's a lucky thing it didn't blow up because it was designed for black powder. After I learned the error of my ways I started using bp shells. Miraculously the shotgun was undamaged and this attests to the craftsmanship and strength of the early Remington shotguns.
Never use smokeless powder in any open breach firearm designed for black powder.
Les