GDay fellas, i'm still saving for that double but I have found something interesting along the way. A Martini Henry .577/450 carbine in very poor condition but the action is good although the barrel has been cut at the knox form, I believe to deactivate it for some reason.
Anyway, I thought why not re-finish it with a new stock (I don't like the MH stock now, too much drop) a good barrel (maybe an octagonal), a different chambering and use it on some buff.

My question is this, since it is a british rifle, I wanna go with a british cartridge and would love to use a nitro (.470NE with black powder loads) but am not too sure what the action can handle, can you guys shed some light? Also, I was thinking the .470NE may be too long to fit down the load ramp. True/false? I'm not really sure about the cartridge selection yet, maybe a 500NE or even a .375 flanged Cheers!

Good Shooting.