6bra new guy

[rr1220]

There seems to be a lot of info available for the ackley improved 6br so Im sure theres a wealth of information that may come my way as a result of this post (I hope)
Ive been shooting a straight 6br for a couple of years now and its an amazing little caliber even in my savage stealth , so I decided to go too a full custom purchased from a forum member here
rifle and barrel specs are as follows
borden brmxd action with 28" krieger 7.5 twist .268nk and .100fb in a glued and screwed terry leonard stock
this is the first time I have spent this kind of $$ and I really want to do everything right
lapua brass turned to .265 loaded using whidden fl non bushing die and expander mandrels , asking for a safe ,accurate FF load using h 4895 and berger 105bts , does it take more than 1 FF to form cases well enough to begin Load development? At what point should I re turn case necks? what would be a good starting point for load development using Barts 103s and h4895 and lastly proper process for FF cases
I have been reading everything I can find on this site and others about all thee above Questions and I realize every barrel is different, again I just want to do this right
End purpose is to begin shooting f class open mid range
Thanks for any and all help and suggestions

 

[NZ_Fclass]

Just my bit - and I dont have a lot of experience of forming cases except for a 243AI, but a friend was forming 6BRX over easter from Norma brass ( Lapua is unobtanium, right now) He was using a false shoulder with a healthy load of 748 with an 85g. The formed cases were a bit soft on the corners, and will need another firing. I suggest that he used a jammed bullet - which is how I form 243AI. It may be worth doing some experiments with different methods to case form, to get the best result without wasting case life and barrel wear. Let alone powder, bullets and primers. If I went down that line for a competition rifle, I would have probably used a Dasher and factory cases....but that's me and I'll stick to FTR/308.

 

[Drolds72]

Use your old 6 br accuracy load to fireform. (I fireformed with 105h, 29.8gr of varget and a .004 jam) Run a seating depth test as well, and you may find, as I and others have, some very accurate fireforming loads. Go shoot a match, it won’t hold you back. They will be pretty much formed after first firing- good enough for load development, and definitely after the second. As far as turning necks and trimming, you will find you won’t have to very often. Just keep checking measurements. On your initial neck turning, take care not to go too far into the neck- you want a slightly firm bolt close to get a good fireform. (if it was a no turn load-shoot, chamber, there would be .004 crush from the br brass to the new bra chamber). Too much into the neck=too much headspace= possible fail to fire.

 

[1bamashooter]

Send brass to DJ he can turn and hydro form them

 

[INTJ]

When I want to fireform in a new barrel, I have had excellent results using 20 grains of Bullseye and 1/8 piece of toilet paper. I also use a soft primer. The last time I did this, after 200 rounds there was just a light haze of gray in the barrel that easily cleaned up.

It does shoot flame out the end of the barrels and the barrel gets hot.

 

[Wild Willy]

When I want to fireform in a new barrel, I have had excellent results using 20 grains of Bullseye and 1/8 piece of toilet paper. I also use a soft primer. The last time I did this, after 200 rounds there was just a light haze of gray in the barrel that easily cleaned up.

It does shoot flame out the end of the barrels and the barrel gets hot.

Bullseye around rifle cases makes me nervous

 

[INTJ]

Bullseye around rifle cases makes me nervous

While we should never be complacent around firearms, using pistol powder to fireform Ackley cases has been safely done for a very long time. The rule has always been to use 70% of a cases powder capacity, NO ADDITIONAL FILLER, and something to hold in the powder. 1/8 piece of TP is perfect. The 6 BRA tunes with 30-32 grains of powder, so 20 grains of Bullseye is about right. Quickload, which is only a rough guide, says this load generates around 50,000 PSI.

While I am not so sure I would load 60 grains to form a 300 Ack, 20 grains in a 6 BR works exceptionally well. You don't burn up 200 rounds of your barrel's most accurate life and you don't waste components on fireforming.

While I prefer to fireform in a dedicated fireforming barrel, when I can't do that the Bullseye method with 1/8 piece of toilet paper is the most efficient and least harmful way I have found to get fully formed shoulders.

 

[arkcomatt]

No need for special fire forming. Load your standard load and go.
For me, 30.7 H4895 behind Barts 103 Dominator. I will be shooting new Lapua brass loaded to that this weekend in St. Louis.

 

[arkcomatt]

Also, no need to go and re-turn brass.

 

[rr1220]

No need for special fire forming. Load your standard load and go.
For me, 30.7 H4895 behind Barts 103 Dominator. I will be shooting new Lapua brass loaded to that this weekend in St. Louis.

Where do the 103s like to be in your barrel
I just bought 1000

 

[arkcomatt]

Where do the 103s like to be in your barrel
I just bought 1000

On this barrel .009" jam. Last barrel .012" jump.