I've experienced this with two rifles now, my CETME and my Mosin. Shooting at 30yds from a bench with a rest I get pretty tight groups, like 1". At 100yds you'd think it would go to maybe 3" but it's more like 8" with fliers going even wider. Both rifles are scoped. Admittedly I haven't had that much practice but when I put the crosshairs on the bulls eye they don't move as I squeeze the trigger and I let the shot "surprise" me so I don't jerk the gun. I try to control my breathing also. So it seems like I'm doing everything right but who knows. I first experienced this with my Mosin and thought maybe it was the surplus ammo I was using so I tried some Winchester with the same results. I use South African surplus in the CETME.