Rifling

Djmudge · October 7, 2012, 07:45 PM

Looking to get the wife a rifle in .223 or .243. What bbl twist do I need with a heavier bullet in the .223.

WIN1886 · October 7, 2012, 08:09 PM

1:9 or 1:8 twist is what I'm looking for wanting to use bullets weighing 55 to 70 grains...too bad really since there are a lot of nice rifles offered in only 1:12 twist which is possibly too slow a twist for longer bullets over 60 grains !

Picher · October 8, 2012, 03:03 AM

In the .243 Win, my barrel maker suggested 1:9, though the Winchester standard is 1:10. I don't normally shoot 100 grain bullets, so it probably doesn't make much difference, but have shot Barnes TSX 85gr. and Hornady GMX 80s; it shoots them pretty well and they're fairly long bullets.

Regarding stabilization; bullet length is more critical than weight. That's why round-nosed bullet often shoot more accurately than pointed bullets of the same weight.

kraigwy · October 8, 2012, 08:03 AM

Quote:

That's why round-nosed bullet often shoot more accurately than pointed bullets of the same weight.

I think you have that backwards. The pointed bullets will be longer then the round nose bullets of the same weight.

Look in any reloading manual that shows the ballistic coefficient of the same cal. bullets. The pointed bullets are longer and have a better BC.

As to the twist recommendations for 223s. Why limit your self. The faster twist will shot lighter bullets as well as heavy bullets. The slower twist will only shoot lighter bullets.

The 1:12 is good to 55 grains, The 1:9 64-69 (if you're lucky), the 1:7 is good to 90 grns.

This chart from an Army Manual will explain what I mean.

kahrguy · October 8, 2012, 08:17 AM

If building the rifle the heavier bullets can perform best with 1-7 or 1-6.5. If buying a rifle it will be hard to find faster than 1-7 . Savage makes some great target/ match rifles.

Djmudge · October 9, 2012, 08:37 PM

I thought about my fm manual to. This should help. Thanks.

October 7, 2012, 07:45 PM	#1
Djmudge Member Join Date: September 30, 2012 Location: Olive Branch, MS Posts: 32	Rifling Looking to get the wife a rifle in .223 or .243. What bbl twist do I need with a heavier bullet in the .223. __________________ Iowa Hawkeyes

October 7, 2012, 08:09 PM	#2
WIN1886 Senior Member Join Date: March 25, 2012 Location: Minnesota Posts: 604	223 Rem. 1:9 or 1:8 twist is what I'm looking for wanting to use bullets weighing 55 to 70 grains...too bad really since there are a lot of nice rifles offered in only 1:12 twist which is possibly too slow a twist for longer bullets over 60 grains !

October 9, 2012, 08:37 PM	#6
Djmudge Member Join Date: September 30, 2012 Location: Olive Branch, MS Posts: 32	I thought about my fm manual to. This should help. Thanks. __________________ Iowa Hawkeyes

October 8, 2012, 03:03 AM	#3
Picher Senior Member Join Date: December 14, 2004 Location: Maine Posts: 3,694	In the .243 Win, my barrel maker suggested 1:9, though the Winchester standard is 1:10. I don't normally shoot 100 grain bullets, so it probably doesn't make much difference, but have shot Barnes TSX 85gr. and Hornady GMX 80s; it shoots them pretty well and they're fairly long bullets. Regarding stabilization; bullet length is more critical than weight. That's why round-nosed bullet often shoot more accurately than pointed bullets of the same weight.

October 8, 2012, 08:17 AM	#5
kahrguy Senior Member Join Date: October 1, 2012 Posts: 561	If building the rifle the heavier bullets can perform best with 1-7 or 1-6.5. If buying a rifle it will be hard to find faster than 1-7 . Savage makes some great target/ match rifles.