6BR Norma -Barrel Chamber

[varminater]

I am about to send in my order for for my 6br barrel and need to give chambering instructions. For those of you in the know, what would be the ideal "no turn" neck size for the chamber? I have heard .272 is about right for Lapua brass but am not sure. I do not want to have to turn any necks if not nessesary. Thanks.

 

[Bob3700]

My reamer from Dave Kiff is a .272 neck and I don't turn any case necks. Works just fine with Lapua brass.

Bob

 

[tiny68]

Well I have ran into some problems with my 30BR which use the same dimensions up the neck as a 6BR. Most 6BR,and 30BR) reamers run 0.471" at the 0.200" datum point. My new lot of Lapua brass is measuring 0.469 and 0.470" at 0.200". That is minimal clearance. I was get the "click" after about 6-7 firings. A lot of guys get +30 reloads with the 30BR. Some say that this could have been prevented if I had a matched custom FL sizer to my chamber. I'll find out, I am getting a few cases ready to send to Harrell's for a custom die. A well respected bullet maker and shooter told me that with the new brass Lapua is making, the 0.200" datum point should be opened up to at least 0.472 or 0.473". If I where building a new barrel I would have Dave at PTG make a reamer according to that. Maybe you don't make as much chamber pressure in the 6BR as we do in the 30BR shooting them wide open and it wouldn't be a problem.

tiny

EDITED FOR TYPO>>> BRAIN FART

 

[varminater]

Tiny,

I just got off the phone about 2 hours ago with Jerry Stiller, Stiller Actions) and he was willing to chamber my barrel with a .274 reamer. As far as I know, it is the only one he has at this time. Is this the right size or should I try to locate someone with a smaller one. Also, what sizing die is best for 6br norma and is there a certain type of reamer I should be using to accomodate that die?

 

[varminater]

Bob,

The .272 chamber was the chamber size indicated when I read the main page, http://www.6mmbr.com/6mmbr.html ) article. Not sure yet what gives here.

 

[varminater]

If I can't get Jerry to get the proper reamer, I will need to hire someone with the proper reamer, hopefully about .272 at the shoulder to .271 at the top of case and thread and install barrel at the same time. Jerry charges $175 to do all of this.

Does anyone know of a good gunsmith who could do this at a comparable price?,and not have to wait forever)

 

[tiny68]

Too many things on the brain this morning. Indeed, its should have been 0.47x" in all my post and the posted above was corrected. My 30BR was reamer with a 0.4707" at the 0.200 datum and it is giving me problems with the last lot of brass I got. My previous 6BR brass was over a full 0.001" smaller at 0.200" than the newest stuff I have.

Maybe I just got a bad lot. Unfortunately I got 5 boxes of it....:,

Tiny

 

[fdshuster]

Had my own .272" 6BR neck reamer cut by Pacific/Dave Kiff 2 yrs ago. Loaded round neck dia. with Lapua is .269". Am extremely satisfied with that combination. Reamer waits patiently on the shelf for its next chambering assignement.