An educatory question more than anything. I was wondering what the proof loads were for particular calibres. I am not sure how true this information is, but for a .577 BP muzzle loading rifle the proof load is 192grn of BP pushing a 724grn bullet. I am more than happy with a 70grn load with a lighter bullet.
The real question is there any verifiable data for proof loads? I'm talking mainly for metallic cartridges rather than BP muzzle loaders. It is purely for personal interest as to what kind of charge my firearms have been subjected to in the proof house.