Alpha 6 BR Brass ruptured Rem 7.5 primers

[Charles Weiker]

I recently aquired some new Alpha 6 Br brass. 30 grs Varget 88 gr. Berger HPFB. I had a couple 7-1/2 rem primers rupture before I caught it. They weren't flattened or pierced. I didn't think this was too hot of a load. Any problems with the alpha Br brass? Primers seem to seat snug ??? Thanks

 

[Charles Weiker]

Bullets were seated with a .010 jump. I'm baffled.

 

[gunsandgunsmithing]

Define ruptured. You said, not flat and not pierced, so blown out? Pic?

 

[Herzo]

I can't speak to the Alpha 6 BR brass, but my Alpha in 260 Remington has substantially lower volume than my Remington brass (55.4 grains vs 57.5 grains of water). Enough to make a significant difference in pressure.

 

[Bill Norris]

I can't speak to the Alpha 6 BR brass, but my Alpha in 260 Remington has substantially lower volume than my Remington brass (55.4 grains vs 57.5 grains of water). Enough to make a significant difference in pressure.

I tried the Alpha SRP brass in my 260AI about a year ago and it simply did not work well at all. Reduced loads from the Lapua brass would not even come close to the velocities of Lapua loads.

 

[762plinker]

I recently aquired some new Alpha 6 Br brass. 30 grs Varget 88 gr. Berger HPFB. I had a couple 7-1/2 rem primers rupture before I caught it. They weren't flattened or pierced. I didn't think this was too hot of a load. Any problems with the alpha Br brass? Primers seem to seat snug ??? Thanks

where did you get the load data??
did you compare case vol of alpha with the load source case volume ??

 

[Charles Weiker]

Like a dummy I used the same load I was using in Lapua brass. This actually seems to have come from the primer pocket. 2 primers had small hole right a the edge it actually cut into the case head a bit and the real bummer it cut into the bolt face on my 40X. I've used there Dasher brass without any issue. Just not going to use this brass. I can square the bolt face. Never thought 30 grs would be too much

 

[Charles Weiker]

When I was a young man I put my 220 swift cartridges up on the dash of my truck driving to shoot ground hogs. Stiff bolt lift and flattened primer. Only other time I had any issues. This was different not stiff blot lift primer showed no signs of pressure. I just won't be using this brass. Thanks for all the input. And Good Shooting.

 

[243winxb]

7-1/2 rem primers rupture

Can be a primer defect issue? https://forum.accurateshooter.com/t...mer-thread-pin-hole-in-primer-radius.4095932/

 

[Charles Weiker]

That is exactly how mine look in that post. I've never had a 7-1/2. Fail before. I did notice the alpha brass has a small ridge or recess half way up the side of the primer pocket. None of my Lapua or Peterson has that or even Remington. Thanks for all your Good help. I new I'd get the answer here. I'll try with the CCI 450 I have

 

[Gunnut26]

That is exactly how mine look in that post. I've never had a 7-1/2. Fail before. I did notice the alpha brass has a small ridge or recess half way up the side of the primer pocket. None of my Lapua or Peterson has that or even Remington. Thanks for all your Good help. I new I'd get the answer here. I'll try with the CCI 450 I have

The Remington 7 1/2 primers that were know to pin hole are the older two anvil primers. When they fixed the problem they went to a three legged anvil. Check your primers make sure they aint two anvils. I had some do the same thing I destroyed them all

 

[Charles Weiker]

These we're old ones I've had for years. I'll be sure to check. Thank you for the heads up

 

[Charles Weiker]

Problem solved. Same load CCI 450 shot great. Old style 7-1/2s shur wish I would have thought to check. Thank you Guys again for all your help. This sight has been a blessing. Good Shooting

 

[Gunnut26]

Problem solved. Same load CCI 450 shot great. Old style 7-1/2s shur wish I would have thought to check. Thank you Guys again for all your help. This sight has been a blessing. Good Shooting

good deal, i thought it might have been the old two anvil primers.

 

[boltman13]

Add me to the list of Rem 7 1/2 edge rupture with Alpha brass and no problem with CCI 450 primer. Now I know what to do. I may be slow but I am trainable.

 

[Kracken McGraw]

Add me to the list of Rem 7 1/2 edge rupture with Alpha brass and no problem with CCI 450 primer. Now I know what to do. I may be slow but I am trainable.

We’re yours the 2 anvil primers or is it a brass problem?

 

[SKWERLZ]

We’re yours the 2 anvil primers or is it a brass problem?

I just looked at the 7 1/2’s I’m running bought in approximately 2014.
3 anvil and run well in my 6BRA with a different brand of brass.

 

[boltman13]

We’re yours the 2 anvil primers or is it a brass problem?

I don't know for sure, but changing to a different harder primer stopped the problem.