The other issue they had was barrel whip as they heated up they would vertical string badly because of the thin non-freefloated barrel and the gas block being used to mount the stock at the front. The 1/10 barrels didn't handle anything heavier than 55gr very well. The 1/9 barrels were very hit and miss on what they liked some would shoot 75-77gr just fine others hated anything except 55gr ball. The 1/7 barrels had the best accuracy potential with defensive and hunting rounds heavier than 62gr. Up through 86 they were 1/10 barrel twist rates, in 86 there was a mixture of 1/10 and 1/7 and in 96 they went to a 1/9 barrel.
