6 BR vs. 6 BRA

[Old Navy]

I have a 6 BR shooting really good with Varget, CCI-450, Lapua brass and 107 SMks. Average velocity out of my 28" barrel is 2912 with no pressure signs.
I have a new 6 BRA. It is looking good with H4895, CCI-450, Lapua brass and 107 SMKs. Average velocity is 2917. Both barrels have 1-8 twist and .104 free bore. Please explain what makes the BRA a better cartridge?

 

[Alex Wheeler]

Not better, different. My last barrel ran 103 vapors at 3040fps with 31.1 of H4895 in a 28" barrel. Your at the low node in the BRA.

 

[KenOath]

I have a 6 BR shooting really good with Varget, CCI-450, Lapua brass and 107 SMks. Average velocity out of my 28" barrel is 2912 with no pressure signs.
I have a new 6 BRA. It is looking good with H4895, CCI-450, Lapua brass and 107 SMKs. Average velocity is 2917. Both barrels have 1-8 twist and .104 free bore. Please explain what makes the BRA a better cartridge?

That’s good speed from a straight BR..What charge you running on both ?

 

[Old Navy]

That’s good speed from a straight BR..What charge you running on both ?

6 BR was a 10 shot group of 30 grains of Varget at 4350' elevation with humidity probably less than 30%. SD 6 and ES 21. It also averaged 2901 with 29.7 H4895. This one didn't shoot. ES and SD terrible. The barrel is a Critorian bull contour. The BRA is 30.8 H4895. Chronograph is a Magneto Speed.

 

[Old Navy]

Not better, different. My last barrel ran 103 vapors at 3040fps with 31.1 of H4895 in a 28" barrel. Your at the low node in the BRA.

Just starting out so I am going to work up slowly. I know I haven't found the node yet. Targets show that with the 107s. Tried some 105 Hybrids with the same load and the groups look better. Of course they shot better because I am on the last box and the whole world is out of them. LOL

 

[JFrank]

I like both but the extra gear of the Ackley is kinda nice to have at a thousand yards.

 

[KenOath]

6 BR was a 10 shot group of 30 grains of Varget at 4350' elevation with humidity probably less than 30%. SD 6 and ES 21. It also averaged 2901 with 29.7 H4895. This one didn't shoot. ES and SD terrible. The barrel is a Critorian bull contour. The BRA is 30.8 H4895. Chronograph is a Magneto Speed.

Excellent speed for 30gns and it shoots… can’t go wrong there IME.. SPJ has a point, for 1k you might see a difference with the extra HP from the BRA..

 

[High Noon]

Old Navy….could you share your 6 BR reamer print.

thanks,
High Noon

 

[Old Navy]

Old Navy….could you share your 6 BR reamer print.

thanks,
High Noon

This is a Savage large shank pre-fit from James at the Northland Shooters Supply. The number on the invoice is 28"-CBI-SM-L/S-BULL-6 BR - 8T. I am sure he could help. He is great to do business with. 763-682-4296

 

[urbanrifleman]

Here's why.

Shoot the 6bra as if it is a 6br. Shoots EXACTLY the same at lower pressure.

Infinite brass life. I shoot 29.6 AR COMP at 2880 in the 6bra with the Berger 108. It is so boring to shoot, the brass never grows, and the primer pockets will last indefinitely.

People are really missing the boat on all the Ackley cartridges. Simply shoot them as the parent cartridge and that is where they actually shoot the best.

That is why you hear so many people report that fireforming shoots bugholes. I have never surpassed the parent cartridge for accuracy in the upper node for any cartridge. Ever.

Here is the thing.... I can shoot the HOT parent cartridge node and the brass isn't even breathing hard.

 

[bugman]

I have a 6 BR shooting really good with Varget, CCI-450, Lapua brass and 107 SMks. Average velocity out of my 28" barrel is 2912 with no pressure signs.
I have a new 6 BRA. It is looking good with H4895, CCI-450, Lapua brass and 107 SMKs. Average velocity is 2917. Both barrels have 1-8 twist and .104 free bore. Please explain what makes the BRA a better cartridge?

you are at the very high node with the 6BR and the lowest node with the BRA. Load the BRA to its high node and shoot both at distance. That extra 100 f/s will answer your question.

 

[urbanrifleman]

The 29.5 fireforming node is about 2880. The 30.4 H4895/ar comp/8208 upper node is about 2940.

I honestly do not get what all the fuss is about. The lower node is much more consistent for the average user. If you want to shoot above 3000 go to a Dasher.

 

[Alex Wheeler]

The 29.5 fireforming node is about 2880. The 30.4 H4895/ar comp/8208 upper node is about 2940.

I honestly do not get what all the fuss is about. The lower node is much more consistent for the average user. If you want to shoot above 3000 go to a Dasher.

In my experiance, if a BRA will run the high node it will shoot better and be more consistent at 1k. The majority of the records have been at the high node. We went from Dashers to BRAs to gain efficiency and agg better. Going back to the Dasher defeats the whole point of it. The best way to do it is shoot both nodes and determine which one shoots best in your barrel. You will get low node and high node barrels.

 

[INTJ]

In my experiance, if a BRA will run the high node it will shoot better and be more consistent at 1k. The majority of the records have been at the high node. We went from Dashers to BRAs to gain efficiency and agg better. Going back to the Dasher defeats the whole point of it. The best way to do it is shoot both nodes and determine which one shoots best in your barrel. You will get low node and high node barrels.

I saw this as well recently. Frequently, the low node would shoot better out of my BRAs out to 600 yds but at 1000 yds, it seems the high node shoots better.

 

[urbanrifleman]

In my experiance, if a BRA will run the high node it will shoot better and be more consistent at 1k. The majority of the records have been at the high node. We went from Dashers to BRAs to gain efficiency and agg better. Going back to the Dasher defeats the whole point of it. The best way to do it is shoot both nodes and determine which one shoots best in your barrel. You will get low node and high node barrels.

Sure I am not discounting that. Just saying for thr average guy not setting benchrest records at 1000, shooting the parent cartridge node is a win, win.

In other words, just skip the 6br and chamber the 6bra and pretend it is a 6br. No downside.

 

[VA_XTC_Shooter]

Sure I am not discounting that. Just saying for thr average guy not setting benchrest records at 1000, shooting the parent cartridge node is a win, win.

In other words, just skip the 6br and chamber the 6bra and pretend it is a 6br. No downside.

except barrel life, isn't it less with a 6BRA?

 

[INTJ]

except barrel life, isn't it less with a 6BRA?

It wouldn't be if you ran it with 6BR powder charges.

 

[urbanrifleman]

It wouldn't be if you ran it with 6BR powder charges.

Exactly.

 

[LRPV]

I saw this as well recently. Frequently, the low node would shoot better out of my BRAs out to 600 yds but at 1000 yds, it seems the high node shoots better.

This is an interesting observation that I’ve experienced with my Dashers. I dropped .3 on HG and .5 on LG from 1k tune to 600 tune. More than that even was last year tuning for 330yd Tackdriver I dropped 1.5 grains from the 1k load. Shooting the same powder (Varget) and bullets and barrel, primers were a different lot but no change in velocity. 1k-32.9@3040, 600-32.45@3000, 300M-31.4@2950.

Hotter charges than 31.4 blew up bad at 330. Got me.

 

[VA_XTC_Shooter]

It wouldn't be if you ran it with 6BR powder charges.

So what’s the point? Same powder charge in a larger case would be less velocity, no?