This is a .450 3 1/4" Black Powder Express. Under no circumstances is it safe to shoot with .450 Nitro Express ammo. The fact that this gun was proved for the Nitro for Black equivalent and is therefore marked with semi-smokeless proof is meaningless - it is black powder proof ONLY. Nitro for Black ammunition was specifically designed as smokeless ammunition that could safely be used in black powder rifles. Pressures were limited to the same standard as standard ammunition loaded with black.

Nitro for Black is black powder, period, and is not the same as Light Nitro.
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