Punctured primers

[Webster]

Loaded up some 6br with 30.5 grains of Varget in Lapua cases and 107 SMK's with 7.5 Remington primers and punctured most of them? The brass was full length sized ,headspace .003 off and trimmed .005 under. Shot some of the same loads with cci's with no problems. There was no pressure signs on case and bolt lift was fine

After 1 punctured primer I never would have fired any more. Safety and bolt face damage.

 

[Ggmac]

After 1 punctured primer I never would have fired any more. Safety and bolt face damage.

ABSOLUTELY ! WORDS TO LIVE BY !

 

[LCazador]

Loaded up some 6br with 30.5 grains of Varget in Lapua cases and 107 SMK's with 7.5 Remington primers and punctured most of them? The brass was full length sized ,headspace .003 off and trimmed .005 under. Shot some of the same loads with cci's with no problems. There was no pressure signs on case and bolt lift was fine

Sounds like you have a large firing pin. If it's a Remington it will do it every time. You will need firing pin turned down to .062" diameter and the bolt firing pin hole bushed. Gre-Tan does an excellent job with the Remington firing pin assembly.

 

[muleman69]

Sounds like you have a large firing pin. If it's a Remington it will do it every time. You will need firing pin turned down to .062" diameter and the bolt firing pin hole bushed. Gre-Tan does an excellent job with the Remington firing pin assembly.

I will get the pin out and check it. It looks to be a large one and hole does look a bit sloppy. Maybe a new spring as well.

 

[Homerange]

Virgin or fire formed cases ?
I never push anything too hard before cases are fully fire formed.....learnt that lesson !

 

[muleman69]

[QUOTE="Uncle Ed, post: 37402552, member:
I appreciate the article , I would send pics. but have not figured that out yet. I have been working on this all morning and conclude that it was pressure/headspace and possibly the firing pin and hole . I pulled bullets and cut back the powder by 1.5 grains and all was fine, all but the pin is striking off center and still have a bit of mushrooming,like pin hole may be to big. Headspace as near as I can tell is around .004-.006. Micked some factory Lapua and it is about .007 shorter than may chamber.

 

[muleman69]

Virgin or fire formed cases ?
I never push anything too hard before cases are fully fire formed.....learnt that lesson !

Both. My chamber is around 1.157 and my die is set at 1.155. Some came out at 1.151 while I was adjusting die.

 

[Homerange]

Both. My chamber is around 1.157 and my die is set at 1.155. Some came out at 1.151 while I was adjusting die.

Another lesson learned then.

Seen plenty a blown primer but always Win LR and from experienced guys pushing things close to the limit.
They go on the edge of the cup and those shooters have vowed and declared not to use Win LR primers again as their bolt faces are a real mess.

 

[Richard Coody]

30.5 of varget in a standard 6br is a stout load. Couple that with the super soft remington primers, and you have what you experienced. Remington primers wont take the pressure.

yep

30 gr varget is my load

and br4's. they have a thicker cup

 

[JFrank]

Pierced Remington primers does not surprise me at all considering the charge of 30.5 gr of Varget.

 

[Webster]

Loaded up some 6br with 30.5 grains of Varget in Lapua cases and 107 SMK's with 7.5 Remington primers and punctured most of them? The brass was full length sized ,headspace .003 off and trimmed .005 under. Shot some of the same loads with cci's with no problems. There was no pressure signs on case and bolt lift was fine

My Berger reloading manual list a max load of 27.6 grains of Varget with a 108 gr BT Target bullet. I have about 20,000 rounds down the barrels of several Rem 700. Never had a leaking or perforated primer.
The Sierra manual list 29.4 grains of Varget max. load with 107 gr. HPBT MatchKing bullet.

 

[muleman69]

Another lesson learned then.

Seen plenty a blown primer but always Win LR and from experienced guys pushing things close to the limit.
They go on the edge of the cup and those shooters have vowed and declared not to use Win LR primers again as their bolt faces are a real mess.

What I'm using is 7.5 rem primers

 

[muleman69]

My Berger reloading manual list a max load of 27.6 grains of Varget with a 108 gr BT Target bullet. I have about 20,000 rounds down the barrels of several Rem 700. Never had a leaking or perforated primer.
The Sierra manual list 29.4 grains of Varget max. load with 107 gr. HPBT MatchKing bullet.

Did some testing today, mine piereced at 28 grains. @27.5 they were a mushroom. My other 6br shoots 29 grain rain or shine. .750 @300

 

[carlsbad]

I just bushed a bolt for another forum member who had punctured 7.5s. I wonder is they got a batch of brass with inadequate ductility.

 

[muleman69]

Pierced Remington primers does not surprise me at all considering the charge of 30.5 gr of Varget.

Yep I here ya ,to much fuel

 

[Dusty Stevens]

Back in the late 90’s before vihtavuori n133 became mainstream we used h322 in our ppc br rifles. As you approached the load that was going to shoot the best it started blanking primers. Another click or 2 got it where it needed to be. Had to carry a bolt disassembly tool to the firing line but it sure shot good

 

[muleman69]

May be something to it.

 

[Homerange]

What I'm using is 7.5 rem primers

Yeah I get that but the cases you're using combined with the stiff load is the issue IMO, not the Rem primers. Blanking primers is different to blowing them. It's partially a headspace and fire forming issue combined with a stiff load.
All wonderful stuff.

 

[muleman69]

Yeah I get that but the cases you're using combined with the stiff load is the issue IMO, not the Rem primers. Blanking primers is different to blowing them. It's partially a headspace and fire forming issue combined with a stiff load.
All wonderful stuff.

I tried the 29 grain load with cci br-4's with no problems? Was blanking rem's at 28 grains? Same cases and HS

 

[mikeeg02]

I tried the 29 grain load with cci br-4's with no problems? Was blanking rem's at 28 grains? Same cases and HS

I would get over the want to run 7.5s. As you can tell they are just so much thicker and tougher than the others. As some claim.

Varget plays well with br4's and 205s, hell 450s even IMO, and Ive tried those combos in 6br's, dashers, br-improved's......

And as I said before, I got away with 205s and your charge with 105s, if EVERYTHING was right. When you dont want to be that fussy, you may get away with running br4's or 450s. But its really best to run one of them at a lower charge when its not so critical. 6br's typically shoot the smallest in the mid to high 2800s. Your mileage may vary.