1 MOA, 1 inch @100 yards, half inch @50, quarter inch @25yards.
I would say if you can hit a large paintball long range or a small paintball short range repeatedly with it is fine.
In hft you have 15mm killzone at short range, long range is what 45mm diameter 40yard ish. This should get you the idea. Clamp The gun down to rule out parallax and shooter, in no wind situation it should be pellet on pellet or at least touching (cloverleaf)