AR-Comp 6BR

[McGee68]

Hi guys, pretty new to this forum and a true beginner with 6BR. I have been reloading for about 4 years in standard calibers .204-30-06.
My question is has anyone tried Alliant AR-Comp in 6BR? I have #8 of it and a selection of 105 A-max and 70 Sierra BK.
Gun is a Savage 12 target with 50 rounds of Lapua 90 gn ammo thru it.
Also looking for suggestions on dies for the factory barrel
Thanks
-Nick

 

[McGee68]

Ok, so much for responses on that. How about IMR 4166?

 

[Shynloco]

Hi guys, pretty new to this forum and a true beginner with 6BR. I have been reloading for about 4 years in standard calibers .204-30-06.
My question is has anyone tried Alliant AR-Comp in 6BR? I have #8 of it and a selection of 105 A-max and 70 Sierra BK.
Gun is a Savage 12 target with 50 rounds of Lapua 90 gn ammo thru it.
Also looking for suggestions on dies for the factory barrel
Thanks
-Nick

Nick,
I have a Savage Model 12 6mmbr that is stock as it came from the factory, but recently replaced the factory barrel with a Kreiger 1:8 after some 4000 rds down her tube. I cannot speak to AR_Comp, but mine has for the past years shot EXTREMELY accurately using VVN133 pushing Bart 68gr Ultras with Berger 68's a close second. And when I say accurately, I'm talking 5 shot groups in the 1's @100 yds. As for the dies, since this rifle was new, I've used Redding Dies to resize, and Wilson Dies/Sinclair Arbor press to seat the bullets. Hope that helps some.

Alex

 

[Dave Berg]

My question is has anyone tried Alliant AR-Comp in 6BR?

I did a lot of testing with AR-Comp and 105 class bullets in a 6BR when the powder first came out. It was originally intended to be a temperature insensitive version of RL-15 but they missed the mark on that when it ended up with a much faster burn rate. Alliant decided it was really a .223 type powder and thus the name was born. Lots of us were hoping it would be what was originally planned but things don't always work out.

It was quite accurate at low velocity. As accurate as Varget and RL-15. This was over several different trips to the range so I wasn't just having a good day.

Where it fell apart is the max velocity I could get without serious pressure signs was 200-250 fps less than Varget and 300 less than RL-15. It might be OK with the 70 grain bullets in a 6BR. Works great in an AR-15. Better, in my opinion than CFE and some of the others as long as you're weighing charges. It doesn't meter very well.

 

[McGee68]

Thanks for the responses guys. I did some testing last weekend with Varget and 105 Amax. Best group came in at 29.6 grains with the bullet .010" off the lands. Group size was just under .750" at 200 yards. Being new to benchrest and the 6br I didn't think it was too bad but I have plenty of work ahead of me.
I will stay away from the AR-Comp and keep playing with Varget and RL-15

Shynloco are you saying your factory gun shot the Barts and Berger 68 that well?? Wow, I didn't think the 8 twist would be the choice for that light of a bullet.

Looking for tips on where to seat the A-max and other bullets in this long throated barrel

 

[rain164845]

I use ar-comp with great results in the 6br with heavy bullets. Similar speeds to varget and great accuracy. Different charge weights, however. I am not near my notebook to give you actual numbers.

 

[fatelvis]

I use ar-comp with great results in the 6br with heavy bullets. Similar speeds to varget and great accuracy. Different charge weights, however. I am not near my notebook to give you actual numbers.

Can you elaborate on your charges Rain?

 

[ncageneral]

I cant say for heavy bullets, 1:14 twist, but I shoot AR Comp under 70 gr Nosler Varmegeddon bullets, CCI 400. Its been pleasantly surprising. I think that CCI 450's might tighten the SD up a bit but have not tried it. As I recall Urbanrifleman steered me in the right direction along with a few others. There are several threads on this issue.
Wow, I didnt realize this thread was this old.

 

[RegionRat]

Can you elaborate on your charges Rain?

Elvis, he was last seen over a year ago, and the post was from 2016, just FYI in case he doesn't answer.

 

[urbanrifleman]

6bra 104 FB

Fireforming load 29.6
High Node 30.4