40yds ish,was 7 or 8 years ago,a mate gave me some to try,he had same problem as me,them eley subs are great,my cz will do 0.5 inch groups at 70yds.
Hard to imagine. My Marlin 880 SQ shoots shotgun patterns with them but most of my CZ guns will shoot them into tiny groups (at closer ranges) for the most part. It must be an odd lot or a pure ammo preference. I have had nothing but good luck with them when shot in a rifle that liked them. How many rounds did you fire, may I ask? ~Muir