Goex Cowboy was designed for black powder cartridge,45 colt,44-40,38-40,specifically for CAS.It is a mixture 3fg and 2fg goex,this was suppose to make it burn cleaner,and to reduce felt recoil.Personally I never noticed any difference between Cowboy and regular 2fg goex,other than price,cowboy being more expensive.I think I would stick with 3fg Goex for cap-n-ball pistols,use the correct lube,and have fun.With black powder clean up is a breeze,I hope this helps...Respectfully Montanadan