Not sure about 200yds, but I shot 8 different slug configurations through my 12 USH. The Remington Buckhammer 3", Breinneke KO's 3", and Brenneke Black Magics were the ticket for mine. The Remington Copper Solids were very respectable, as were the old stand-by Winchester BRI's. It has been awhile, but if my memory serves me well......my gun DID NOT like Hornady SST's or Barnes Expanders. Seems the higher velocity loads overall were not quite as accurate out of this 1/35 twist barrel. Good Luck to You!