The two in the photo are 45-70 cartridge. I can shoot BP in them. I shoot some BP in my Browning, but not in my Sharp's. You can get blowback in the Sharp's. I also shoot BP in my Winchester 1886. Iam looking at a couple different single shots for BP only, but I have not ponied up the bucks yet. I am looking real hard at one of the Gibb's rifles. Tom.