1:7 vs 1:9 which is more accurate?

[GONIF]

that's what I have observed,the 1/12 is perfect for XM193 or Q3131a.

Another error from that stupid link is that 1/12 doesn't stabilize a 55gr bullet. 1/12 stabilizes 55 grain just fine. In fact, as a general rule, 1/12 gives optimal accuracy for 55 grain projectiles.

[marty]

One thing I am trying to get a better handle on is twist rate and bullet stabilization at long distances - practical experiences, not theorethical exercises. I had a similar post on another thread - so I'm repeating myself here a little. I'm not talking 100 yards, I'm talking a much longer range.

For example, with my 1/9 twist 16 in barrel, with 55gr M193, I can get sub MOA at 100 yards on paper and can hit 3ftx3ft and 2ftx2ft gongs out to 600 and 650 yards with no problem.

My 1/12 twist Browning bolt action (.223 chamber) w/22 in barrel does not handle ANY 55 gr .223 load that I have tried well at all. At 100 yards at best I get 1.5 inch groups with ANY load. I've tried 50 gr too and the improvement over 55 gr is marginal. But with 45 gr it becomes a tack driver (at least in my definition and my abilities) with consistent 3/8 in groups at 100 yards and 1 inch groups out to 300 yards on paper targets on a windless day. I have not put bullet to paper with this gun past 300 yards. I have not shot M193 thought this gun as it is chambered .223 and not 5.56, so I don't want to get into a chamber pressure issue.

So - when people say that 1/12 stabilizes 55 gr, or 1/7 stabilizes 55 gr just fine .... my question is: at what ranges and at what level of accuracy at those ranges? I am curious as I am about to pick up a 1/7 and am interested in people's experiences with 193 at long ranges (ring the gong or put a hole in the paper is the only objective at those ranges).

[RogerinTPA]

which is more accurate,1:7 or 1:9 twist?

Depends on a lot of variables: type of ammo, manufacturer of the barrel/weapon, whether it's a match or stock barrel, skill of the shooter (the most important variable IMHO), ect... The 1:7 barrel will give you the largest range in types of bullet weights. 55-75 grain and higher. My 1:7 barrels shoot 55 grains pretty accurate. More accurate than some 62 and 75 grains. YMMV.

[Blackwater]

Pictures are worth many words and each rifle is unique.

Colt M4 Target, w/ 1-7 twist rate. 5 shots 100 yards with ACOG TA01-NSN 4x32
and 55 gr American Eagle. Make shift rest on range bag.



She's a keeper.

[Failure2Stop]

Individual barrel quality and ammunition consistency will play a larger difference in applied accuracy than the difference between 1:7 and 1:9- as long as each is fed the appropriate ammunition.

[Battl3fr0nt]

no matter what anyone says it is all up to your gun.. most 1/9 will shoot 75gr fine.. mine does, if you are going to be shooting alot of 800m + stuff then a 1/7 is for you if you are only going to be shooting 800+ once in a while 1/9 will be fine.. I have not found a 1/9 yet that will not shoot 75gr ammo and 1/9 twist will wear better. you can tell by shooting at 100 yards and if you keyhole then your gun will not shoot that ammo.. I would not go past 77gr with a 1/9. and it really is only worth going with 1/7 if you are going to shoot 77gr ammo more then 50% of the time.. and as for accuracy you will want a 1/8 match grade barrel.. it is more about how well the barrel is made then the twist.. I have seen 1/10 shoot better then 1/7

[carbine85]

My HB Varmit with a 1:8 twist shoots better then my 1:7 or 1:9.
The 1:8 doesn't like the lighter rounds but shoots the hell out of the 69 & 77's

[CarlosDJackal]

I have a 24-inch Bushy Varminter that has a 1:9 twist and likes the Black Hills (Blue box) 75-grain BTHP. I have shot this combination out to 926-yards with great effect (as long as I do my part).