I'm planning to put a new barrel on my .243.

Thinking 24" for speed, and am trying to figure out best twist rate.

Will be shooting Barnes 85grain TSX, but want to be able to shoot heavier bullets and lighter bullets for varmints. Currently thinking I go 1:9.

Would appreciate opinions.

Thanks

I shoot a 243 AI with a 24 inch 1:9 twist barrell. It groups well with 100gr "conventional" bullets (and below). And it will stabilize a 95gr Berger VLD. But when I shoot 115gr Berger VLDs the groups open to 2" at 100 yards and the bullet holes look "ragged" rather than crisp. The holes were torn as the bullet wobbled through the paper vs. punched.

I have heard that some folks get 1:9 barrels that will handle 115gr Sierra MK and Berger VLDs very well by mine will not. So you might want to consider a 1:8 twist just to be sure if you looking at those heavier target bullets.

Barstooler

Yes a 1:9 "might" work. However a 1:8 won't hurt a thing and will remove all doubt as to working with heavy bullets.

1 in 8 is the ticket!!!!


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I've never come across a 6mm bullet of 105 grains or less which wouldn't stabilize in a 1-10" .243. You would see little or no difference with a 1-9 twist, so if that's what floats your boat, go ahead.

You suffer some theoretical velocity loss (though very small) and/or pressure increase (also very small) as you increase the barrel's rate of twist. You also increase the amount of torque (yes, it does exist) on the rifle from the barrel imparting a faster spin to the bullet. This torque force is so small that it will likely never be noticed in a rifle shooting 100 grain bullets, but when you get up in the 300 grain range with something like a .338 Lapua then the torque can be an issue and require some type of compensation.

quote:

I've never come across a 6mm bullet of 105 grains or less which wouldn't stabilize in a 1-10" .243.

Normal lead bullets I agree with you. I have never attempted any of the VLD bullets. Just going by what Shilen has on their spec sheet.

The 1-10 Krieger stabilizes the 95 VLD and all 100 gr bullets. Never tried or wanted anything heavier.

1-9

I am kind of a 1 in 8 guy for 6mm. Works a plumb for my BR and 6mm Ack improved Rem.

I shoot everything from 60's to 115 DTACs.

I have used the BR at 1000 yard comps and it works well.

I'll never own anything less than a 1:8 twist barrel when using a custom tube. Buying a factory rifle ill not buy one with a 1:10 twist anymore. There are a lot of good bullets that are better suited to a faster twist in a .243 to even consider a 1:10 anymore.

Thanks guys.