Optimum 6.5 Creed twist for heavier bullets

[Soulwood]

I am ordering a custom barrel for my 6.5 Creedmoor. I will be shooting Berger 153.5 long range hybrid target bullets most of the time, and 140’s once in a while. My question is - what would be the optimum twist? 7 1/2? 7?.

 

[ruger35]

I think either of those are fine for the 153s. I tried them in a 1:8, probably could have done some more tweaking to the load, but it was much easier using the 144s.

 

[wpeach1912]

7.5 should be plenty unless you’re running really slow at sea level

 

[FuhQ]

I am ordering a custom barrel for my 6.5 Creedmoor. I will be shooting Berger 153.5 long range hybrid target bullets most of the time, and 140’s once in a while. My question is - what would be the optimum twist? 7 1/2? 7?.

According to Berger's stabily calculator (at 0' ASL, since I don't know you're elevation), the 7.5" twist would be comfortably stable (1.58 SG) for the 153.5's, and a 7" twist would get you a 1.82 SG, which is VERY stable. So, if you're specifically planning to shoot only 150+ grain bullets, then the 7" twist might be ideal. But if you plan on dipping down into the 140's, the 7.5" twist might be a better compromise, since your 153.5's will still be considered fully stable, but you also won't be overspinning the 140's.

 

[Rob01]

7.5 will be fine. I shoot 153 ATips in my 8 twist now and they are very accurate. I just ordered a PVA Osprey in 7.5 twist as I plan to shoot the 153 only in that barrel.