223 twist

[boyshooter]

say i had a 223 and was firing 55grn soft points and i had a 1 : 9 twist barrel would it be better to have like a 1:12 twist for a bullet this many grain?

 

[Tim the student]

1/9 should be fine.

I have a 1/8 that shoots 55 grainers fine. I suspect it should shoot 50s fine too, but its new and I haven't played around with it that much.

I have another 1/8 that shoots 50 and 55 very well.

 

[230RN]

I've got a 1:14 Savage in .223 Rem which shoots light 50-55 gr bullets superbly. Heavier, not so much.

 

[W.E.G.]

The rule of thumb is you cannot OVER-spin a bullet, but you can under-spin one.

The wild card is that some very light bullets have jackets so thin that the jacket is damaged in a fast-twist barrel. When this happens the bullet will not fly true.

 

[boyshooter]

so from wat ive heard it will shoot 55 50 fine but wat about faster bullets like 60 - 70 grn with the 1:9

 

[Davek1977]

I don't understand your question, as it flies contrary to common knowledge. The heavier a bullet is, the slower its going to travel. Therefore, a question about "faster" heavier bullets like the 60-70 grainers doesn't make sense. A 1/9 twist will stabilize everything from 50 to 70 pretty effectively in most rifles/carbines

 

[Art Eatman]

Heavier bullets are longer and thus require a faster rate of twist in order to stabilize. Shorter bullets, while stabilized with a slower twist, are still okay from a faster-twist barrel.

There is thus a range of bullet weights which give good groups in any particular twist-rate barrel.

W.E.G.'s comment about thin jackets is appropriate for some bullets in fast twist-rate barrels. There are varmint bullets designed for lower velocities which will indeed come apart with high velocity and fast twist. Those designed for the .22 Hornet, for instance.

1:9 should work just fine for bullets from 40 grains to 70 grains; maybe even a tad heavier, but I'm not experienced there.

 

[aka108]

I have a Howa 1500 in 223. The twist is 1-12. 55 grain shoots beautifully. Anything heavier just doesn't work. The 1-9 twist is probably the best since it will handle about anything run thru it with a high level of accuracy.

 

[mtrmn]

If you had a 1/12 you'd be limiting yourself to about 55gr and lighter bullets. Any heavier than 55 gr may not stabilize well with 1/12.

1/9, 1/8, 1/7 all seem to do well with anything 50 gr and up. My 1/9's seem to do best (accuracy-wise) with a 60gr Sierra Varminter, with a 69 gr SMK running a close second.
If you want to get above 70 gr, better go with at least 1/8.

 

[helotaxi]

I've shot from the 36gn Varmint Grenade to the 75gn Hornady HPBT match bullets from my 1:9 Savage and my 1:9 and 1:7 ARs. The fact that I live well above sea level and don't typically shoot in sub-zero temps might have something to do with the fact that I've never had stability problems with the 75gn bullets (note that I'm talking about the HPBT not the Amax).

Unless you're planning on shooting the long range bullets, a 1:9 will be fine. If you think that the 75-80gn Amax or 77-90gn SMKs are in your future, you'll need a faster twist. 1:8 will handle pretty much everything but the 90SMK. The Berger VLDs are a bit of a wildcard.

 

[boyshooter]

thanks guys i know wat to get now

 

[Art Eatman]

Ah, satisfaction!