6mmbr rechamber

[moe africa]

Hi all
I'm currently looking at rechambering a new Howa 6mm creedmoor to 6br having looked at the chamber diagrams
My idea is to cut 1.150" off the creedmoor
Thus the diameter of the remainder of the chamber would be 0.4714"
The reason why I'm not considering purchasing a new barrel as it has to be licensed separately in South Africa
Would this be viable

 

[divingin]

I think the 6BR cartridge has more taper then the 6CM. You'll need to cut enough to allow a full chamber cut in 6BR. Is your twist rate going to be suitable for 6BR?

 

[moe africa]

I think the 6BR cartridge has more taper then the 6CM. You'll need to cut enough to allow a full chamber cut in 6BR. Is your twist rate going to be suitable for 6BR?

It's a tad fast but not too bad 1 in 7.5

 

[bugman]

My concern would be the amount of barrel breach steel remaining.Once you accomplish getting that 200 line past the Creedmoor shoulder OD, your next issue is the short distance of 1.17" barrel OD remaining at the breech. IMO, this should not be trusted for high psi 6BR loads, and should be dedicated for low round count hunting situations. That is another problem because a 7.5 twist will prefer the heavier/longer bearing surface bullets.
I would never pay a smith to do all that work, and would find a suitable trade or sell the creed and buy what I wanted.

 

[divingin]

It's a tad fast but not too bad 1 in 7.5

That is what I run in my long range 6BR barrels. Twist rate should be fine.

I should have mentioned the concern that Bugman referred to. You'll need a decent amount of untapered barrel ahead of the barrel shoulder to do this successfully.