Fire forming 6BRX

[RLP]

After reading many threads on this, I plan to use virgin Lapua (blue box) with 30.5 varget and 107MK jammed .030 to form my 6BRX,thinking it will do well. My question is this, Do you get a full shoulder with the ff load or does it take a 2nd firing to iron out any incomplete discrepancies. Is there a method or a way to know for sure. My only experience with this is doing 20 Vartarg. Thanks Bob

 

[DukeDuke]

you should get a full shoulder
l use 30 gr. of rl-15 and 105 a-max and always do get a full shoulder

 

[DJSBRS]

I can Hydro-form them for you for .50¢ each and you won't have to burn your components, barrel, gas to the range and time up.

DJ

DJ's Brass Service
205-461-4680

 

[RLP]

Thanks DJ, but I will do most of my FF in prairie dog towns in So Dakota. Bob

 

[jr600yd]

Your load should do fine. If your using a Remington action (or similar) remember the ejector will push the case away from the bolt face. Make sure you have a hard jam.

 

[tclaunch]

Fed 205`s are another plus if not using the false shoulder, even if you do use the false shoulder they work great for fireforming.

 

[DMC]

Fed 205`s are another plus if not using the false shoulder, even if you do use the false shoulder they work great for fireforming.

+1 on this
I used the 205's with a hard jam and plenty of neck tension with 107 smk and varget to fire form my last batch, worked well, there is plenty of very experienced brx/dasher guys on here, they helped me a great deal when i started with a Dasher. they have "been there, done that " many times

 

[RLP]

Thanks, I will give the 205's a try. I have them in stock. Appreciate the info. Bob

 

[AckleymanII]

Better yet, remove the ejector!!!!

 

[Longone1]

Can you tell me the advantage of using the 205 primer over let's say a 450 ?

Thanks, Longone

 

[nosualc]

30.5gr sounds a little hot for fire forming. I've used 30.0 but got about a 2-3% failure rate (burst shoulders). I've had better luck at 28.8. Last time I fire formed at 28.8, I didn't lose any.

I'm cool with this as I think it's easier on the primer pockets, which eventually (5-6 firings) expand enough to take the brass out of service.

It's been my experience that ff'ing the brass will seldom result in nice crisp shoulder edges. Usually takes a second full BRX load to get that.

It's also been my experience that ff loads can be very accurate indeed. I try to do my fire forming on our weekly f-class league nights, where a few extra X's don't matter.

-nosualc

 

[tclaunch]

Can you tell me the advantage of using the 205 primer over let's say a 450 ?

Thanks, Longone

The 450`s have a thicker (harder) cup, the 205`s with thinner cup are easier to ignite. You can get misfires with hard cup primers.

 

[Longone1]

Got it, thanks TC.

Longone

 

[jerdebson]

DJ, does Hydro-forming fully expand the brass to the BRX specs?

I can Hydro-form them for you for .50¢ each and you won't have to burn your components, barrel, gas to the range and time up.

DJ

DJ's Brass Service
205-461-4680

 

[DJSBRS]

I will say it is over 98% formed and is ready for a full load of powder. There is a slight radius but not much. You will be competitive in a local match shooting them as they come from me. They will be within .001 headspace from a batch of 400.

My smallest 5 shot group at 520 yards was 1.163" shooting them for the first firing.

DJ

 

[jerdebson]

Thanks DJ, another question that came up is do hydro-formed cases grow in length or stay shorter than wanted by most? TIA.

 

[DJSBRS]

Look at it this way, if you are using new 6 BR brass that is X in length, then you want the sides to be wider and the shoulder to be longer, the OAL has to shrink to expand to the other dimensions that one is expecting it to expand to.

There is only so much brass to start with. Once it has been expanded (by firing or Hydro-formed) then the necks will start to grow as the brass flows forward. Sizing the necks starts to push the necks thickness inside and back down to the shoulder neck junction.

I look at it like a water filled balloon. Where ever you push it or mold it, the balloon or brass will go another way. Narrow the brass and it will grow, widen the brass and the OAL will shrink. In some cases more or less than others.

Hope I didn't confuse you.

DJ

 

[jerdebson]

Thanks for that DJ, I appreciate the info.

 

[DennisH]

What is the process to fireform Dasher Brass?

DJ, I will get you to fireform my next BRX batch. PM info, prices.

Dennis