I didn't want to sway the opinions of those responding.
But I am guessing at least 200 yards. Fired rounds today with 450 gr bullet, Fg powder with Cream of Wheat filler. Very little fouling...
50 and 100 yards did not hit target. Various shots at about 15, 25, and 35 yards (approx) will keep a group well under 1", but 5" high, then 7" high, then 10" high. So still climbing and probably well over target at 50 (and 100?) yards...