Chambering 6BRA?

[Terry]

I used a 6BR go gauge. No problems.

 

[Alex Wheeler]

Any reason not to just have someone like manson make you a dedicated bra go gauge off a print? (like alex’s jgs)? and space chamber as normal? am i missing something?

You can, no problem. But I use only direct measurements for headspace so for me it makes no difference. If you want to close on a go and not close on a go with tape on the back, get a gauge made. I find minus .002" is about where most brass has a good fit. I like guys to fit the brass to their chamber by bumping the shoulder until they get the right feel on the bolt. You form better cases when they fit properly. I know many in the prs world are chambering so no fitting is required and that is also fine for them.

 

[dnellans]

at risk of derailing - i used to size specifically to “feel” on closure like i think you’re implying.

but every 100 or so rounds i would end up with just one case that would stick like it was pressure signs. because i’m picking brass up off the ground, culling those cases is nearly impossible. i’ve had to start making sure i don’t have any friction to eliminate that hard to eject case. which leads to shooting for a 1.5-2 thou setback on shoulders.

is there something else i should be suspect of or consider? hopefully we’re talking the same feel on closure.

 

[Alex Wheeler]

I like a snug fit for forming only, not for normal shooting. I do not want to feel a formed case when closing.

 

[dnellans]

thanks for reply alex

/derailment off

 

[Badbob]

Curious why the BRA is .004 shorter? My reamer drawing for my 6mmBR shows 1.239 to the shoulder/neck.

My BRA reamer drawing shows 1.2364" to the shoulder/neck. By my weak math skills that is a difference .0026"

Another curiosity is that at the bottom of my JGS reamer print it says "Uses the standard BR (0020) for a headspace gauge"

I'm getting ready to re-chamber a 6mmBR barrel to BRA so I sure would like to get this correct--I guess then not just a curiosity. Thx BB