• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

6BR and AR Comp load

Finally got my 12 twist 6BR barrel from X-Caliber. Took off the temporary 8 twist Shilen and put the 12 twist on and went to the range. Loaded up new Lapua brass with AR Comp and Berger 80 FBs. Just thought I would test around the 29 grain area. It was breezy and about 35*. Shot ten 5 shot groups at 100 yards. Found that for some reason 29.1 grains sucked and of course I had loaded the most rounds at that weight. Got two groups in the .0s though. :) Anyone need a Shilen 8 twist 6BR barrel with 100 rounds though it? LOL

qA880iH.jpg
 
I just finished my new bench gun. 12 twist Brux. 6bra. 50 fb for the Berger 80.

I'm going to test AR COMP of course and some other stuff :)
 
I have a question about hard bolt lift. My 12 twist 6BR shoots pretty well with AR Comp around the 29.2 grain range. The problem is a hard bolt lift. I dropped down the load to test around the 26-27 grain area and it still had hard bolt lift. The primers looked OK. Tried a small base die last night to see if it makes a difference and loaded 50 rounds with 29.1 and 29.2 grains of AR Comp and Berger 80s and went to the range this morning. Shoots great but still have hard bolt lift and the primers looks OK. Even had a 0.07" or so 5 shot group at 100 yards. The accuracy goes down below 29 grains so should I give up with AR Comp even though it sure shoots accurately?

2UHBsv1.jpg
 
I have a friend getting hard bolt lift at anything over a modest charge.
I suggested a touch more sizing at the shoulder rather then the base.
J
 
What action is the rifle? If it is a Savage, the bolt lift is less than stellar. There are kits available and @Grimstod can work on the bolt to improve the lift effort, he did my PTA and it is nice.
Jonathan Taylor

The action is a Bighorn TL3. I got lift kits for my Savage target actions and the kits made a big difference.
 
I have a friend getting hard bolt lift at anything over a modest charge.
I suggested a touch more sizing at the shoulder rather then the base.
J

I bumped the shoulder back 0.002. Should I increase that to a 0.003 bump and try that?
 
Do you occasionally feel some cases having a little friction when closing on them or are they all as good as an empty chamber? .002 is usually good enough as long as the brass isn't springing back inconsistently. its worth trying .003 on a few just to see if it helps but i wouldn't do them all that way until you test, that will also squeeze the base .001 further down too.
 
Do you occasionally feel some cases having a little friction when closing on them or are they all as good as an empty chamber? .002 is usually good enough as long as the brass isn't springing back inconsistently. its worth trying .003 on a few just to see if it helps but i wouldn't do them all that way until you test, that will also squeeze the base .001 further down too.

The bolt closed down nicely with no extra pressure needed.
 
I had a chamber done by a local guy. Bolt lift on every round was so hard the bolt handle broke off.

Had nothing to do with the load. I think he polished the chamber.

This thing shoots pretty well so it would be great to be able to use AR Comp at an accurate load. After shooting even low loads around 26 grains, I have to bump the shoulder to have it chamber with no extra pressure on the bolt. I can't recall how it was with the 8 twist Shilen barrel. Maybe I should switch back to that barrel and see how it acts. I think the 12 twist X-Caliber barrel works better with the 80 grain Bergers though.
 
I bumped the shoulder back 0.002. Should I increase that to a 0.003 bump and try that?
Damn sure won’t hurt ya.
I had to increase mine to .0025
1.569 FF
1.5665 F/L
Chambers freely, shoots great without problems out to 30.1 gr Varget 107 gr SMK
 
Ar Comp is an amazing powder. Why it is completely ignored I have no idea.

Should really be quite good for any bullet weight in 6br from 55 to 115. It's nearly perfect for 70 to 108.

It's like a couple guys tried it on this forum a decade ago, said it was too fast for 105s and that was gospel. Then it was forgotten at Accurate Shooter Forum.

It is essentially interchangeable with h4895 for burn rate and velocity. So in practical terms it does the same job as one of the most popular powders on this forum, IS LESS TEMP SENSITIVE, has much better lot consistency, and is far easier on the barrel with a decoppering agent that actually works...

It must be the name. If it was TZ 1234 it would be the secret sauce of the elite I suppose hahahaha
 
Ar Comp is an amazing powder. Why it is completely ignored I have no idea.

Should really be quite good for any bullet weight in 6br from 55 to 115. It's nearly perfect for 70 to 108.

It's like a couple guys tried it on this forum a decade ago, said it was too fast for 105s and that was gospel. Then it was forgotten at Accurate Shooter Forum.

It is essentially interchangeable with h4895 for burn rate and velocity. So in practical terms it does the same job as one of the most popular powders on this forum, IS LESS TEMP SENSITIVE, has much better lot consistency, and is far easier on the barrel with a decoppering agent that actually works...

It must be the name. If it was TZ 1234 it would be the secret sauce of the elite I suppose hahahaha
Now if it had a name like "Creedmoor Comp".......
 
Ar Comp is an amazing powder. Why it is completely ignored I have no idea.

Should really be quite good for any bullet weight in 6br from 55 to 115. It's nearly perfect for 70 to 108.

It's like a couple guys tried it on this forum a decade ago, said it was too fast for 105s and that was gospel. Then it was forgotten at Accurate Shooter Forum.

It is essentially interchangeable with h4895 for burn rate and velocity. So in practical terms it does the same job as one of the most popular powders on this forum, IS LESS TEMP SENSITIVE, has much better lot consistency, and is far easier on the barrel with a decoppering agent that actually works...

It must be the name. If it was TZ 1234 it would be the secret sauce of the elite I suppose hahahaha


I actually tried N135 in this 12 twist barrel and the AR Comp seemed more accurate with the 80 Bergers. The big difference was when I cleaned the barrel. After shooting with AR Comp, the first few patches would be black then the rest would be reasonably clean after that. After shooting with N135, it looked like a colony of smurfs took up residence in the barrel. I couldn't get the patches to stop coming out smurf blue and just gave up.

BTW, I swapped barrels to the 8 twist Shilen and will go to the range today to see how the bolt lift is after firing.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
166,252
Messages
2,215,051
Members
79,496
Latest member
Bie
Back
Top