6mm BRA primer pockets loose.

[Mastershot]

My pockets are getting very loose after 2 or 3 firings with 30.7 gr of H4895. Should I switch to Varget? I dont have this problem in my dashers.

 

[KenOath]

My pockets are getting very loose after 2 or 3 firings with 30.7 gr of H4895. Should I switch to Varget? I dont have this problem in my dashers.

What bullet are you running? I know a guy running the 108s opened primer pockets fairly fast.

 

[Mastershot]

What bullet are you running? I know a guy running the 108s openened primer pockets fairly fast.

105 hybrids with 7.5 twist barrel, I am thinking 30.7 grains of H4895 is too hot. Its a very accurate load moving the bullet at 3005 fps.

 

[mikeeg02]

Fall out loose? Or just eeeasssssyyyy to go in loose?

What primers? I would suspect 450s?

 

[Mastershot]

Fall out loose? Or just eeeasssssyyyy to go in loose?

What primers? I would suspect 450s?

Go in way too easy with 450’s yep. My buddy had this same issue with his BRX after 2-3 firings and the primers where just falling out during shooting.

 

[Sheldon N]

105 hybrids with 7.5 twist barrel, I am thinking 30.7 grains of H4895 is too hot. Its a very accurate load moving the bullet at 3005 fps.

3005 fps is moving pretty good for a BRA, what barrel length? I'm at 30.4gr of H4895 and am getting 2919fps from a 27.5" barrel. My other BRA is 26" and 30.6gr gives me 2896 fps, both 105 hybrids.

 

[Kyle Schultz]

31.1 gr H4895 and BIB 104s. CCI 450s. Running 2990-3000 fps out of 28" barrel. 4th firing. No problems so far.

 

[Mastershot]

3005 fps is moving pretty good for a BRA, what barrel length? I'm at 30.4gr of H4895 and am getting 2919fps from a 27.5" barrel. My other BRA is 26" and 30.6gr gives me 2896 fps, both 105 hybrids.

Mine is a 28” Krieger barrel.

 

[Mastershot]

31.1 gr H4895 and BIB 104s. CCI 450s. Running 2990-3000 fps out of 28" barrel. 4th firing. No problems so far.

Nice.

 

[Kyle Schultz]

You want to know nice?

At the end of an afternoon of load testing last week, I put 3 rounds downrange at a steel turkey. 400 yards. Hit 3 for 3. I love this gun.

 

[mikeeg02]

Go in way too easy with 450’s yep. My buddy had this same issue with his BRX after 2-3 firings and the primers where just falling out during shooting.

You might try a 205, BR4, or maybe 400s, though I have no experience with 400s.

I had a batch of brass I shot in my dasher, and with 450s, they felt loose sooner than I expected. I think my lot of 450s was smaller in diameter than the 205s and BR4s I have. Which I believe contradicts the table floating around showing approximate diameters. When I went to 205s (or BR4s cant remember) they felt tight again, and lasted to 15 or so firings before the end of the season. May be worth a shot, but at 3,000 fps node, it only takes one hot day for a spike and you can easily weaken the primer pockets some.

On the other hand, I have a different lot of brass that I shot the same lot of 450s with and the same load you listed, and those cases lasted a long time. But my velocity at 30.7 I think was 2980ish. You may have a fast lot of powder.

 

[Jet]

What is the free bore on that barrel?

Recommend going down to the lower node. Accuracy will likely still be great.

Rich

 

[farmerjohn]

Ran into the same problem with 4895, bout pulled my hair out fooling with it. Could not get past 2950 without too much pressure. Tried varget and it was better but accuracy wasn't near as good. Tried 8208, walked up to 3050 before I ever felt the bolt start to have any resistance and great accuracy. Backed up .2 of a grain and shot the same case ten times in a row and the primer pocket was still good. CCI 450, lapula, 103 Bart's, es8, give it a try... I've been happy with it.

 

[dkhunt14]

What is your freebore? Many factors can cause this. Too slow of barrel, too big of reamer at .200 line, too fast of lot of powder, too much powder, fat bullets and a few more things.Matt

 

[Mastershot]

Ok, here is my reamer print.

 

[johara1]

I think the biggest problem is the lots of H4895 vary a bunch. I have 6 different lots some shoot some don't, some build pressure fast and no velocity and some are super hot......jim

 

[Jet]

View attachment 1080024
Ok, here is my reamer print.

If you stick with the same bullet, recommend retuning at a lower node and your brass will last longer than the barrel.

Good shooting

Rich

 

[CaptainMal]

BRA's run best in the lower to mid 2900 fps range. You are sure pushing it to go over 3,000 fps. Though that can easily be done ,it may be part of your problem.

Carbon fouling causing any increased pressure and higher velocity? Just a thought. That is a difficult and common problem with most all the BR case variations. Serious cleaning is a must with the BR case.

 

[farmerjohn]

+1 on what johara said, try another powder. I would have tried another lot of 4895 but it's a crap shoot to go buy another 16 lbs just to find out. I know that 8208 works for me and I have plenty of the same lot.
Farmer

 

[T 700]

How temperature stable is 8208?