6mm BRA primer pockets loose.

[Delfuego]

My last Kreiger took 1 grain less powder than the one before it for the same speeds.

I think Lapua brass is a crap-shoot sometimes too. I have some Hydro-Formed Dasher brass from DJ's that is falling apart after 2 firings. You could have toasted your brass.

I also think you should listen to CaptainMal and Sheldon. You are going to fast...

 

[Bugs]

My experience has been that russian primers, Wolf in particular run a few tenths "fatter" than BR4's or 450's. You might want to try some (if you can find them) to take up some of the space in that brass with loose primer pockets.

 

[johara1]

+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

I found a better way, I get a pound of each lot and try them and the one that works I go buy more like a case. I used the same load in the same barrel with the different lots and Labradar tells me if it is running the same or nearly the same velocity and the target tells the truth on the lot..... jim

 

[Mastershot]

Guys, thanks for all the help.
I am going to go out and change the primers to Fed Match and lower the amount of powder with a starting amount like 30.0 grains and work it up from there on this twice fired brass. Once I find a lower node in the low 29’s, I will run some of the once fired brass to see if the pockets start to loosen up.

 

[farmerjohn]

As for temperature stable, I've been using it for Prairie Dog shooting for several years in small cases, PPC, 6br, 223s, ect. 110° in the Tex panhandle and no problems at all, that's the reason I had it. I am staying between 2995&3020 and staying around 2" or less at 600 if I do my part. Pretty good shooter that holds a world record with a bra told me about the crazy lot differences with 4895 and suggested trying 8208. Since I already had 32 lbs of the same lot I did, been happy ever since. AND, I think it's a lot easier to clean up behind, lots better than varget. My two cents worth....
Farmer

 

[Gilbert Garza]

I will run some of the once fired brass to see if the pockets start to loosen up.

One thing I’ve been doing lately with all the latest and greatest caliber is I’ll take 10pcs of brass and run them through the rifle with various loads, check the dies, measure to reamer dimensions and various other things over the course of 100rds. So I’m somewhat seasoning the barrel (clean shoot clean) but also testing to make sure my brass/dies will last 10x firings before I start running all my brass through the rifle. It also tells me what direction the barrel wants to go in for powder, barrel.

 

[dmoran]

@Mastershot
Questions:
- on the culprits, what do they measure for diameter at the webbing, before the expansion line?
- then again after you have sized them, what do they measure?
(See image below)

 

[Willow]

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.

30.6gr of H4895 with Berger 108s jammed produced too much pressure in my rifle and the primer pockets opened up super fast. Backed it off to 30.2gr and jumped them to alleviate that problem.

 

[johara1]

I don't shoot 108's but a number of 103-5 's shoot well with 31.0 - 1 H4895 without issues. Sounds like a fast lot of H4895 and or the 108 bullet combination..... jim

 

[Kyle Schultz]

I'm no expert but if there's one thing I've learned from spending 10 years on this board is that EVERY barrel, bullet, lot of powder, etc is different. You have to figure out what works in your gun.

Here is my 400y BIB 104 ladder test from a few months ago. I'm posting it not to brag but to show the Labradar velocity data I recorded that day.



I DID NOT experience any pressure signs and I think it's pretty clear why I settled on 31.1 grs H4895. The only change I have made to the load since then is to reduce the jam from 0.010" to 0.005".

The Berger 108BT tuned at ~ 2930 fps using 30.5/30.6 gr H4895 and with the bullet jumping about 0.007" Those bullets performed very well if I sorted them with my Bob Green comparator.

So, IMO, to imply unequivocally that 2920 fps is the ONLY velocity target for the 6BRA is open to debate.

Merry Christmas and good luck to everyone.

 

[bcarico]

If you hit any Ackley or wildcat to hard fireforming it will decrease bass life due to primer pocket failure.
May not be the original posters problem but could help someone.

 

[expiper]

how big is your chamber at the .200 line,,,if its big ,,,the brass will swell to match it and the pockets will get loose,,my BR's and Dashers are all .471 and I have never had an issue ,,,they work in concert with Redding Type S dies,,,,,,Roger

 

[Mastershot]

@Mastershot
Questions:
- on the culprits, what do they measure for diameter at the webbing, before the expansion line?
- then again after you have sized them, what do they measure?
(See image below)

View attachment 1080181

I will have to measure this after I shoot this next batch. I do know that my sizing die is resizing it back to off the top of my head and I could be wrong at .267-8ish.

 

[Mastershot]

30.6gr of H4895 with Berger 108s jammed produced too much pressure in my rifle and the primer pockets opened up super fast. Backed it off to 30.2gr and jumped them to alleviate that problem.

I think you nailed it. I am jammed just a bit, I will try it where my dasher loves them. That brass is tight at 10 firings.

 

[Mastershot]

how big is your chamber at the .200 line,,,if its big ,,,the brass will swell to match it and the pockets will get loose,,,,Roger

I will check on my next outing.

 

[steve123]

I had decided to use light loads in my new 6mmBR. Trying 4 different bullet types and two of them just running the barrel in on steel for a little over 100 rounds.

Then I did a ladder test with twice fired brass, using a neck die the second firing(the only die I had from years a go - but I have a harrells FL die coming soon) and found that my barrel liked 30.4 grains of Varget with 105 hybrid.

Going against my original idea, with the remaining 50 virgin brass I decided I'd load the 30.4 gr load. Went to seat bullets and the load was so compressed I couldn't even seat a bullet all the way in. I must have a pretty loose chamber since I'm just neck sizing and the body hasn't been sized, abundance of case volume I suppose??

Anyway, I'm pretty sure if I'd been able to seat a bullet in that virgin brass I would have ruined the primer pockets, whereas with no case body sizing the 30.4 gr load doesn't appear to be over pressure.

I pored the powder back in the hopper and reduced the load 3%. Hopefully I reduced the charge enough.

Now I think I better do another ladder test with the brass FL sized, darnit!

 

[dkhunt14]

I will check on my next outing.

Only the reamer print will tell you that. Fired brass will never measure what the chamber is. Matt

 

[dkhunt14]

I think you nailed it. I am jammed just a bit, I will try it where my dasher loves them. That brass is tight at 10 firings.

.4 grains of powder in a case this size is a pretty substantial reduction. That would give more pressure reduction then moving the bullet from touch to In the lands.

I have had barrels with the same twist from the same company and one could shoot a full grain more powder then another. This was with a Dasher with the same lot of powder, bullets and brass. Some barrels just can't shoot as much as others. Matt

 

[dkhunt14]

how big is your chamber at the .200 line,,,if its big ,,,the brass will swell to match it and the pockets will get loose,,,,Roger

His print is shown on an earlier thread. .4714. Matt

 

[Northridge]

I'm no expert but if there's one thing I've learned from spending 10 years on this board is that EVERY barrel, bullet, lot of powder, etc is different. You have to figure out what works in your gun.

Here is my 400y BIB 104 ladder test from a few months ago. I'm posting it not to brag but to show the Labradar velocity data I recorded that day.

View attachment 1080246

I DID NOT experience any pressure signs and I think it's pretty clear why I settled on 31.1 grs H4895. The only change I have made to the load since then is to reduce the jam from 0.010" to 0.005".

The Berger 108BT tuned at ~ 2930 fps using 30.5/30.6 gr H4895 and with the bullet jumping about 0.007" Those bullets performed very well if I sorted them with my Bob Green comparator.

So, IMO, to imply unequivocally that 2920 fps is the ONLY velocity target for the 6BRA is open to debate.

Merry Christmas and good luck to everyone.

kyle, I would agree my finding considering a BRA and all the reloading components and manufacturing options with barrels and actions to say they usually shoot better in the low 2900's has not completely been my finding but partially. there is some trickery that will affect results but heaver bullets above 105g and a few options in the 105g class 2920fps to just shy 2950fps will give some Steller results depending on components and physical barrel used. I have handled a given manufacture that really shines in this region. now the best barrel or platform I have had and others I shoot with often slam tight tunes right off or on 3000fps with a particular brand of barrel bullet combo. So all I can suggest is don't just look high or low its nice to know a working ceiling but if brass can not handle said plan choke your tuning back until you find it, it is there even dropping into high 2800's has given me small groups as well as 50 & 100 scores. don't worry about the velocity or BC with in reason. best advise I could likely share is this shit can chrono graph and shoot in a little bit of condition as you develop a relationship with your rifle, stack the odds against the platform and it will give you all kinds of data to study.

Shawn Williams