6BRA new chamber issue

[Forward543]

I just chambered a new barrel in 6BRA. I shot the previous barrel 2200 rounds and am switching. This is a new jgs #1 BRA reamer. It is different from the original. All of my brass sized down, seems to be .001" too big. The new chamber is tighter, i can get some of the brass to chamber, but does not go smooth. My whidden die does not seem to size the base down small enough. I have not tried new brass. Do i need to get a small base die, and if so from where? Can you just cut the top out of another br die? Or is there a better option than buying new brass. I have 400 pieces and want to get cooking. Thanks.

 

[djporter]

Try a 243 Win f/l die

 

[ballison]

I ran into the same issue with a new 6x47 barrel and a small base die did fix the problem. Not sure when they might be available, but this is a good option. I would try emailing them.

https://patriotvalleyarms.com/universal-small-base-bushing-die/

 

[blowemup]

Good rule of thumb is new barrel new brass...
You could have the smith use your old resized brass as the go-gauge on your new chamber
though if the reamer is different you may run into trouble once you fire a round the old brass may spring back & click on extraction.

 

[Raythemanroe]

How much do fired pieces measure vs sized at the shoulder? Maybe just a body die although I would fire those that chamber and call Harrels. You probably are looking at a D-3 80 short.

Ray

 

[Forward543]

How much do fired pieces measure vs sized at the shoulder? Maybe just a body die although I would fire those that chamber and call Harrels. You probably are looking at a D-3 80 short.

Ray

Fired are .003 longer at the shoulder. The .243 full length die is dropping them to where they will chamber, but it is difficult. My though was size it all, and shoot another fireform lot on them. So far after fireforming, they resize and chamber well.

 

[rsmithsr50]

if just the base, try a 308 win sb die

 

[Nightraider]

A carbide 45acp is the best option here.

 

[rsmithsr50]

why ? more likely to have a 308 around, and probably easier to get.
will the case only base size and still clear the die on a 45 die ??

A carbide 45acp is the best option here.

 

[Raythemanroe]

Fired are .003 longer at the shoulder. The .243 full length die is dropping them to where they will chamber, but it is difficult. My though was size it all, and shoot another fireform lot on them. So far after fireforming, they resize and chamber well.

Seriously, just call Harrels with your fired measurements. They will have you something in a couple days.


Ray

 

[coldboreshot]

Good rule of thumb is new barrel new brass...
You could have the smith use your old resized brass as the go-gauge on your new chamber
though if the reamer is different you may run into trouble once you fire a round the old brass may spring back & click on extraction.

+1 on the opening line. Unless you are chambering barrels in a series with same reamer. "Reloading is like a box of chocolates..."

 

[Nightraider]

why ? more likely to have a 308 around, and probably easier to get.
will the case only base size and still clear the die on a 45 die ??

Which is where the issues lie

 

[Alex Wheeler]

The .2" line on that reamer is .4714". Your old chamber was fat most likely. A Harrell's #4 BRA die will fix that. But just use it once. With JGS reamers with the same body specs you should be able to use the same brass in all your barrels.

 

[Forward543]

The .2" line on that reamer is .4714". Your old chamber was fat most likely. A Harrell's #4 BRA die will fix that. But just use it once. With JGS reamers with the same body specs you should be able to use the same brass in all your barrels.

Oddly enough that is what the finished chamber roughly measures on your reamer. The .243 die is pushing the case in enough to chamber. And subsequent sizing is feeding fine. Is there an issue with doing it this way? I am full length sizing them after sizing the body with the .243.
Thanks

Seth

 

[Alex Wheeler]

Just get a BRA#3 from Harrell's and everything will be good.

 

[Forward543]

BRA #3 inbound. Is there any reason to run a low pressure fireform on first firing? Or just do regular workup. Last barrel was 31.1 4895 with 105 hybrid. Going to check this one from 30.0-31.4. hawk hill 7.5 26".
Thanks

Seth

 

[rsmithsr50]

yes to FIRE FORM without abuse.
they seem to last longer this way

 

[Raythemanroe]

BRA #3 inbound. Is there any reason to run a low pressure fireform on first firing? Or just do regular workup. Last barrel was 31.1 4895 with 105 hybrid. Going to check this one from 30.0-31.4. hawk hill 7.5 26".
Thanks

Seth

You always work up and do a new ladder test for new barrels and brass

Ray

 

[Boatschool02]

I always run lower pressure fireform loads as I'm fairly conservative on brass treatment, anyway.
Had a certain barrel pressure MUCH earlier than expected, even during the first forming trip.
Having done otherwise, who knows how bad it might have been.
I've seen some stupid high FF charges used/survived/advocated, but prefer to decide for myself, anew, each barrel.
-
Depending on your discipline, I would consider setting aside 25-50 pieces of new brass for testing only.
Log everything. You'll have a fairly good idea where the the new barrel is lining up.
I then form the remaining cases with the same charge and they only ever see consistent (non max) match charges. I had one barrel keep speeding up for 160 rounds, so with the BRA I elect to form the first 200 cases on a new barrel during this semi-lost window of break-in. After you've burnt out one barrel it can be pretty handy for fireforming going forward. The other current post on chamber differences is a solid reason to consider starting a new build with two barrels or at least owning your own reamer.

 

[Forward543]

All of this is solid info. I own the reamer, and chambered this barrel. The previous was from another company. Shooting fireform 105 hybrid load appears to be shooting outstanding. They are running 2730,a very nice 100 yard group, and it appears putting a water line at 500. They are chambering rough, but extraction is smooth. Will fireform all the brass, then resize with Harrels #3 BRA die. Hopefully full power loads shoot this well.