1-10 twist

[Guest bigpa]

hello ladies and gents,

I just purchased a sig 223 with a 21 inch barrel One 10 twist,I am new to the AR family don't know really too much about rifle twists.any suggestions on what weight of bullet I can shoot out of this rifle.I will be reloading. Can I use a 62 grain bullet with this twist ?any help would be appreciated.

Thanks bigpa

[lowery100]

A 1:10 twist will be better suited to 55gr or less. It would not hurt to try some 62gr bullets, they may do o.k. but the lighter bullets will most likely be your best bet.

[Lumber_Jack]

I had a cousin that couldn't get betters than 4" groups at 100 yds with 55 gr and 1:10 twist. He moved down to 50 gr and you could cover the shot holes with a quarter. The slower twist rate will not stabilize heavier bullets as well as lighter. But I'm of the mindset that, 'it never hurts to try'! Just don't buy a 500 rnd case until you know how well they work.

[Dave Shooter]

Faster twists are needed to stabilize longer (which usually, but not always, means heavier) bullets. 1-12 is more than fast enough to stabilize conventional 55s. The military went to 1-7 to (over)stablize their 62 bullet which is longer than a conventional lead core 62 gr bullet due to the penetrator. I've seen 1-9 be fine for 69 gr. Sometimes even what's not supposed to work works just fine. So.... give it a try!

[leroy]

bigpa:_____________

We used to shoot 223 boltguns with 1 in 12 twists when the best 22 caliber bullets 52 to 55 grain. They would shoot like a house a fire; usually you could lay a dime over a 5 shot group from 100 yards from a good solid bench with a 12 or so power scope. I would try the 62 grain bullets (...just as Dave said above....); as a 62 grain bullet aint that much heavier, and a 1to 10 twist is just a bit faster than the ole 1 in 12 and a bit slower that the "optimum" 1 in 9 that lots of the ar guys use (...includin me...).

My guess is that you will get good results because the Sig guys are engineers as well as manufacturers and have probably looked at this pretty hard. There is a definite relation between velocity, diameter, bullet length (....diameter and bullet length determine bullet weight to a large extent....) and twist rate. I would suspect that the Sig guys have looked into all this and everything should be cool. Ya may have to play around a bit to find the "just right' load for your rifle, but that's part of the fun of shootin.

Have fun and let us know how this turns out.

leroy

[Dolomite_supafly]

Faster twists are needed to stabilize longer (which usually, but not always, means heavier) bullets. 1-12 is more than fast enough to stabilize conventional 55s. The military went to 1-7 to (over)stablize their 62 bullet which is longer than a conventional lead core 62 gr bullet due to the penetrator. I've seen 1-9 be fine for 69 gr. Sometimes even what's not supposed to work works just fine. So.... give it a try!

Not true.

They went to 7 twist to stabilize the super long NATO spec tracers not the 62 grain bullets. The tracers only weigh virtually the same as 62 grain bullets yet are about 1/4" longer than those same bullets. 9 twist is plenty fast for 62 grain bullets. 9 twist will easily shoot 69 grain bullets. 9 twist will also shoot bullets heavier than 69 grain accurately in most guns.

Just to reiterate, they did not go to 7 twist for 62 grain "penetrator" bullets but to use the NATO tracers.

Dolomite

[Dave Shooter]

DS is as usual on top of his game about the tracers.

I didn't mean to imply 1-9 is inadequate for 69 gr; I've never seen them not shoot well in 1-9.