Ace if you realy want a short range bench gun try a 250-3000. I put one together and 100gr. smk's shoot like a laser and the 90gr. smk's are not far behind. The 25 cal. bullets make a little bigger hole also, and that matters shooting score targets.
Mine is done as a 1:10 twist 18" Douglas match in a plum colored Stocky's thumbhole.