6BR Norma Twist Rate

[South Pender]

I'm considering a used rifle in 6BR that has a 1-10" twist. Not the twist I would like since I'm interested in primarily 100-200 yd. shooting and the tightest-possible groups with 68-70-gr. BR bullets. If I were to go the custom-build 6BR approach, I would order a 1-14 twist; a 1-12" would have been OK too. Can you guys tell me how much of a disadvantage I would be at with this 10-twist barrel given my plans for the rifle?

 

[big bad bill]

Dear South Pender,
I shoot 6BR in 14, 13.5, 8 and 7.5 twists. With the 14 and 13.5 twists, I can shoot in the mid .1s with Berger Columns and LT-32 for 5 shot groups at 100 yards. In the 8 twist, with some slight node changes, I can only shoot from .25 to .3 inch groups with the same bullets. I would expect you may get slightly less performance in a ten twist vs 14 or 13. If you want to shoot 68 and 70 grain flat based bullets, 13 or 13.5 twist would give you more bullet stability than 14.
I hope these observations help.
Good shooting,
Bill

 

[vtmarmot]

With a 10 inch twist, some prefer the 88 grain Berger but I like the 80's myself. Have never had a reason to go lighter.

I've been shooting 108 Bergers in the 8 inch twist with good results and am about to try 105 Bergers and 105 A-Max for variety.

 

[snakepit]

Go to www.bergerbullets.com/twist-rate-calculator and put in your specific variables. Your variables may differ from the variables of those making recommendations. Example, the twist rate of a barrel may be stable at the high altitude of Denver and marginal or unstable at sea level.

 

[dreever]

I had a ten twist that shot 90 grain Berger boat tails in some phenomenal groups at 200 yards. If you go with the ten twist you really should try that bullet.

Danny