115 DTACs - What twist?

[jlmurphy]

I am hoping for some feedback. I have a 1/8 twist Hart barrel chambered in .243 Win. I have been shooting 107 and 115 gr. match bullets from a 29" barrel. This barrel is over it's mid life and when I replace it, what twist rate is necessary to stabilize 115 gr DTACs? The .243 can be hard on barrel throats and I have toyed with rechambering in a smaller case 6mm, although these may not have the capacity to push the 115's. Does anyone have any recent experience with this issue?

 

[Rtheurer]

Bryan Litz's book is almost required reading. He also has a program that will tell you what you need to know and you can manupulate the velocity to get diffrent answers to your question and make a good quality descision based on information you researched.

If it where me I would pick something in the 1:7.5 to 1:8 twist range with the deciding factor being the case and velocity I expect to get.

Im sure this Question has been asked a thousand times here on this forum. Do a search and see what you come up with.

RussT

 

[rcw3]

A true 1:8" will do it but it's right on the edge. Hart barrels usually are a little over an 8" twist and I have had Harts that will stabilize DTACs and Harts that won't stabilize them, so running a Hart is a bit risky.

I have had very excellent results with Bartlein 1:7.8" twist barrels with the DTACs. You can use 1:7.5" twist barrels, but don't go tighter than that as there can be other issues (pressure problems).

Robert Whitley

 

[82boy]

When I talked to David Tubbs, he told me that the bullet will stabilize in a 1 in 8 twist barrel if you push it 3000 fps. I have shot them in my 6x47 lapua 1 in 8 twist 29 inch Shilen ratchet twist, and they did fine.

 

[wc872]

I get 2939fps corrected (+9 fps) for muzzle velocity in a 6XC with 115 DTAC's BN. I have a Broughton bbl. which is a 1:7.5 twist. This combination has proven itself very accurate from 100 - 1,000 yards. When replacement time rolls around I will be replacing it with a 1:7.5 twist.
Semper Fi