hi guys
ive acquired a james beattie and sons sxs hammer shotgun with jones rotary underlever
the gun has twist steel barrels with bad pitting halfway along bores
im toying with the idea of building a double rifle out of it
obviously id stick to a blackpowder calibre in keeping with style of gun
my initial idea would be to cut the barrels back and sleeve/thread a pair of rifle blanks into them
i can get a pair of .50 cal barrel blanks so maybe .500 bpe?

any advice/ideas greatly appreciated
ive done a fair bit of engineering work in the past and have built several bolt actions
so no hassles there