BRX starting to pierce primers???

[Raptor]

Guys I have a bit of a problem. The other night when I was out shooting I fired a round in a 5 shot string and I could not open the bolt. I had to tap the bolt open with the handle on my heavy hammer. The primer was completly gone and the case was stuck to the bolt.

After getting it off the bolt I checked everything and it was all fine so I fired several more rounds and they were fine no problems. THen on my last group I pierced another primer.

When I was out last night I had another one pierce out of about 30rds. There is no heavy bolt lift or other pressure signs and I have shot this load for over a year with the same 8lb jug of powder. The load is 33.4grs of Varget. Even though this is at the upper edge I have had no problems or pressue signs before now. Any ideas??

 

[7stubby]

Outside temperature could play a part, if you worked a load up in 50-60 degree temps and then shot them in 70-80 degree temps. Also do you have your firing pin hole bushed? What brand and type of primer?

 

[DJ111]

Carbon ring in the throat, I would start there.

What primers are you using?

New lot of bullets?

 

[Thorbird]

I use 32.5 of varget, never had a problem with that load, but I use Wolf SRM's and sometimes 450's. They are both thick cups.

 

[bozo699]

Guys I have a bit of a problem. The other night when I was out shooting I fired a round in a 5 shot string and I could not open the bolt. I had to tap the bolt open with the handle on my heavy hammer. The primer was completly gone and the case was stuck to the bolt.

After getting it off the bolt I checked everything and it was all fine so I fired several more rounds and they were fine no problems. THen on my last group I pierced another primer.

When I was out last night I had another one pierce out of about 30rds. There is no heavy bolt lift or other pressure signs and I have shot this load for over a year with the same 8lb jug of powder. The load is 33.4grs of Varget. Even though this is at the upper edge I have had no problems or pressue signs before now. Any ideas??

What scale setup are you using? what was the temp when you worked up the load and what was it when you were shooting the problem loads? what kind of rifle? has the firing pin been bushed? and what primers? Do you have carbon built up? were they 400 by chance or 205's? the pierced primers are normal when your at the top of your range and using 400's or 205's as they are soft, it is why most use 450's or br4's or Russian primers but the one that would bother me was the one with no primer and had to beat the bolt open, that one sounds like about 2 grains more powder to me, so I am wondering about your scale.
Wayne.

 

[Josh11]

I would have to agree with Wayne on this one. Check the scale. Are your groups still holding together? Or did you get a crazy flier when this happens? Is there any way your primers could have been mixed?

 

[BoydAllen]

I think that you put too much powder in the cases. If it was carbon, it seems to me that the problem would have been more consistent, and not just a shot here or there. As far as mixing primers goes, I suppose that could be an issue, since I have seen a primer change, without dropping back and reworking the load, do the same thing on a load that was on the ragged edge in the first place. I would have to vote with Wayne. Do you look at the powder level of all of your cases as they sit in a loading block, before seating bullets?

 

[Hal]

Have you disassemble your bolt and checked for primmer pieces in the bolt body?
Also look at the end of the firing pin and see if it's eroded.

You might also check your case length.

Hal

 

[BoydAllen]

Case length is a good tip, and although It is unlikely, check case "headspace". A case that is technically the correct length, but which has its shoulder too far back, will be driven forward so that the neck is crimped into the bullet, and pressure will increase markedly.

 

[DennisH]

I actually had a problem with my sear, Savage PTA action, BRX, started piercing primers. Changed the sear out (after scratching my head for 8 weeks), reset the headspace, and have been shooting ever since. I only use CCI 450's.

All we can figure out is the sear wore just the right amount to cause the problem. I used this actions for several builds.

JMO

 

[Raptor]

Rifle is a Remington 700 with a Kreiger 1-8 I am using Vargert and the load shot fine all last summer. I use CCI450s and Wolf SRM primers. I started off with the 400s and they were piercing with fire forming loads.

No, the bolt has "NOT" been bushed but once I went to the 450s and Wolfs I had no more problems. Normally the bolt opens right up no ejector marks.

One of you guys mentioned mixing up primers and as I think about it this could be a possiblity. I had some sitting in a primer tray and they "Possibly" could have been some 400s I didn't use but I can't think of when I would have left them out but with my mind I guess anything is possible. Thanks for the ideas guys!!! Really appreciate the thoughts!!

 

[SDDasher]

Send your bolt off to Greg Tannel (GreTan) and have it bushed and the problem will go away. I had the same issues with my BRX and had it bushed and bingo, bango, no more pierced primers. I was using CCI 400, and CCI 450's. JMHO

 

[BoydAllen]

Looking at the original post, the primer being completely gone, and the case stuck in the bolt face was a severe over pressure issue, not just some pierced primer thing.

 

[Raptor]

Boyd I agree totally, but my scale checks out to within a tenth of a grain. There is no way to double charge a BRX case when using 33+grs of powder. The load is nearly up to the neck of the case. I took the bolt apart and looked at the fireing pin and it looks great on the end. No cutting or pitting.

 

[rcw3]

Any way you cut it 33.4 gr of Varget in a case the size of a BRX and pushing 105-108 gr bullets is a hot load pressure wise so if you are piercing primers you either have to back off your load or find a more "bombproof" set up for the ignition of the primers (i.e. whether it's verifying the cups in the primers you are using are up to the task or re-working the firing pin set up in the bolt, etc.).

 

[Raptor]

I may try backing it down some I think I had a node at 32+ that worked well too. Thanks for all the replies guys really appreciate the input.

 

[bozo699]

Looking at the original post, the primer being completely gone, and the case stuck in the bolt face was a severe over pressure issue, not just some pierced primer thing.

This was my concern all along,....the one that was stuck and primer gone! pierced primers in a brx or dasher when pushing the pressure envelope is common from what I have observed the last 4 years shooting beside 30+ guy's shooting dashers and brx rifles in the matches I go to in Montana, imho it had to be a screw up on powder or I hadn't thought of the case being to long and crimping itself, that easily could have done that as your already pushing it. every gun is different, I have a 6brx Lawton 7500 that can't come close to 34 grains of Varget, I think about 33.2 is it and my son has a Savage 6brx that loves 34.5 grains of Varget, shoots it very well, primer pockets go south pretty quick but no ejector marks, anyway hope it all works out for ya.
Wayne.