It's my understanding that when the M16A2 was being developed it was planned for a 1/9 twist to shoot the 62 grain FMJ bullets. The problem was for the tracers. They were longer but lighter because they were hollow for the phosphorus compound that would light as the powder burned. To be accurate it needed a 1/7 twist to be accurate.

Due to a miss communication all barrels in the M16A2 became 1/7 twists. If it wasn't for that mix up there would be no 1/7 twist barrels or there would be very few of them and they would be highly specialized. This information came directly from a fellow who was involved in the development of the M16A2 while he was active duty Army. As it appears, the 1/7 twist is a really great twist for the shorter (14.5") M4 barrels. I guess you could call it a "happy accident".

I have a 1/12 twist Remington that really shoots the light weight bullets very well but at 60 grains the accuracy starts to fall off. I have not tried a 62 grain bullet in it. I just don't see the logic. Do I wish it was a 1/9 twist ? You bet, but I can make the 52's and 55's work. I have a Ruger American and some AR's for anything heavier than 60 grains. I understand the new Remington's in .223 are now 1/8 twist. I think that is a good choice for an all around rifle. The exceptions would be for the super light and the super heavy bullets.

This has been a great discussion.

kwg

For liberals and anarchists, power and control is opium, selling envy is the fastest and easiest way to get it. TRR. American conservative. Never trust a white liberal. Malcom X Current NRA member.