6mmbr in ar15

[sonex184]

Is there anyone shooting an ar15 in the 6mmbr? I know there are in the 6mmAR.
I just built 2 ar15 uppers in the 6mmBR cal. and I'd like to have some feedback on loads, problems, etc..
So far I'm getting .500 inch groups on the average. I want to take the ar15 to SD pd hunting this summer.

 

[forsyth793]

Can you share some of your build procedures with your 6mmBR/AR-15.

 

[sonex184]

I used a 1-13.5 tw bartlein barrel, a dpms hi-rise upper receiver, a 458 socom bolt from RR Arms, and turned the barrel, cut to 26', chambered .272 no turn nk. Had to tweak 6.8 mag to feed, 223 mags work with a little more mods.
Haven't shot 80 gr. bullets yet but 70gr noslers shoot good.
I'm building a 2nd upper light weight for a walking rifle.

 

[justonemorear]

I work at a class 7 manufacturer and have seen 17Rem and 20Tacticals.

 

[sonex184]

I just opened up a 223 bolt to .478 and reground the extractor. Bolt works fine for 6mmbr. I went to the range and shot 50 rds the other day. I'm pretty pleased with the accuracy, 1/2' groups average. no feeding problems. 34gr. varget, 55 noslers bt seem to work great. I'm working on a 70gr. load next.

 

[rifleman1]

Sonex,
I emailed the fella about the 458 socom bolt and he told me the 458 socom bolt would not hold up to the pressures of the 6mmBR, so be careful with your handloads.Thanks for your help with my project.
mike

 

[sonex184]

Thanks for the advice but I know what I'm doing. Good luck on ur project. I'll let u know how everything went after I get back from pd'in in S Dakota. I'll have about 500 rds through the gun.