Just did my BC a couple of weeks ago...took a 3/4 inch piece of copper pipe about 9" long and filled it with lead....It must be about 3 or 4 pounds. It was so heavy it stripped out one of the wood screws holding the metal butt plate on. So I took the stock off my muzzle loader and put that on..but made sure the lead tube was snug insiden the bolt hole channel this time. Works great, but I won't be carrying it around much... Also tried a 405 grain slug at 2000 fps.....ouch....I mean OUCH...
Now I'm back down to 1750 fps and I think I'll stay there, but the extra weight off the shooting bench still helps.....Norm