I have a Ruger 10/22 with a short 12" barrel that give a 1" group at 50 yards using Winchester 40gr expanding ammo, it would do a bit better if I tried harder but for bunny's it is just fine. Now today I put a Edgar Brothers moderator on it and went to check the zero hadn't moved. I found that it now performs like a shotgun and I struggle to shoot a 2" group!!!
What's gone wrong? Do I need to try different ammo or a different moderator? Thoughts please ...