.243 Winchester Rate of Twist

[asimpleman]

I have recently decided to purchase a rifle chambered in .243 Winchester. I have narrowed my choice down to two rifles and though one has more "options" and appeal to me, I just wanted to get everyone's opinion and/or experience with rates of twist.

One rifle has a 1:10 twist rate while the other has a 1:9.25 twist rate.

I will be using factory and hand 100 gr. loads for whitetail and smaller (I don't particularly know what size be it 55, 75, 82, 95 gr or what) for coyotes.

My main concern is will the .75 rate of twist be a big deal for one load or the other? I.e: Will the 1:9 be good for the lower grain loads and terrible for the heavier loads? Will the 1:10 be good for lower grain loads and terrible for the heavier loads? or vice versa.

Thanks for your input,
asimpleman

 

[jbkebert]

I have two rifles in .243 winchester. Both have a 1:10 twist barrel one is a 28" and the other is a 24". Both rifles have done very well with any grain bullet I have fired from them. Had poor luck with a couple diffrent bullets but another brand or make in the same weight worked fine.

I have fired 55, 85, 95, and 100 grain bullets from these two guns. Don't know about the 75's or 82's never tried them out.

 

[Coltdriver]

Generally, the heavier the bullet the tighter the twist you want.

But the reality is the longer the bullet the tighter the twist you want. Go take a look a Berger and Barnes. Both are very long bullets, they want a 1 in 9 or better, a 1 in 8 twist.

Most bullets under 75 grains will work just fine in up to a 1 in 12 twist. Some will work great with a 1 in 13 or 1 in 14 twist.

Most (except ones like the Berger's and the Barnes) 100 grain bullets will stabilize in a 1 in 12 twist. Even better in a 1 in 10. So if you want to shoot both 100 grain and say 68 or 75 grain I'd go for the lowest twist I could get, not for the lighter bullets but to stabilize the heavier ones.

 

[GP100man]

I have qwiker positive results with the faster twist in 243/6mm rifles .

 

[RainDodger]

1 inch difference isn't going to be noticed... not in my mind anyway. Just like jbkebert, I have 2 .243s - one Browning BAR and one Sako heavy barrel Forester, and they're both 1:10. Both have handled any bullet I've put through them, although the Sako does definitely like a 90 grain bullet best of all. (a Berger, to be specific) The BAR enjoys 100 gr. bullets for sure. I've gone lighter in the Sako with pretty good luck also.

 

[LoonWulf]

My savage with a 9 1/4 wont stabilize anything heavier then 105, but everything up untill that shoots great. If your not going to be launching VLDs, a 1-10 should be fine up to around 100. My 6x47 has a 1-10, and ive launched 95grn vlds at 2900ish and gotten them to stabilize out to 200 or so, didnt have a farther shooting area at the time.

 

[243winxb]

Its the length of the bullet more then the weight. A flat base 100gr may be more accurate than a boatail 100gr. The 1:9.25 twist rate. is better for the heavier longer bullets. But 10 works. The VLD bullets seem to be the longest. See Bergers website, they list twist rates for each bullet. Good all around bullet, is the Sierra 85gr hpbt GameKing #1530 loaded with IMR 4350 or H4350.

 

[Shurshot]

Berger's website doesn't even list a recommendation of any of their .243 bullets for a 9' twist. the 88 gr Match Grade High BC FB Varmint bullet comes closest with a 10" recommended twist and it is the longest bullet they have listed.

in the varmint bullets that is...

 

[Jasper1573]

Recommend the 1:9.25" twist...if you want to shoot bullets with high BCs, this will allow it as well as bullets with lower BCs also. The slower twist will not do as good a job across the board.

 

[kelbro]

I would buy the Savage, but I'm lefty and Savage has supported lefties through the years. Don't obsess over it though. 1:9.25 and 1:10 are 'references' and not necessarily exact. I have measured some Savages that were 1:9 and some that were 1:9.5. Also some 1:10 Remingtons that were 1:9.5.

Most all of them shoot the 100gr bullets (and lighter) well.

 

[243winxb]

243 win & Rifling Twist

Berger's website doesn't even list a recommendation of any of their .243 bullets for a 9' twist. the 88 gr Match Grade High BC FB Varmint bullet comes closest with a 10" recommended twist and it is the longest bullet they have listed.

in the varmint bullets that is...

A 1-10 or 1-9 twist can handle 68gr to 90gr Bergers at 243 velocity very nicely. Hunting, target or varmint. And i would guess even ligher bullet, as i have not shot ligher than the 68 gr. Berger has in 6mm, 1 hunting bullet & 3 varmint bullets that will work well in a 1-10 or 1-9 twist Sierra 100gr flat base will work, but not as good as the shorter bullets in 1-10 twist. Sierra bullets will get the hunting job done, at less cost per shot.

 

[tlen]

http://www.ammoland.com/2008/11/29/best-bullet-weight-for-your-gun/

http://www.shilen.com/calibersAndTwists.html