Load Master
Member
I learned something new about Sellier & Bellot primers. Their large rifle primer comes in two different flavors. There is the 5.3 LR and 5.3 LR-SE. S&B's usage chart shows the LR-SE is needed for .308 Win. I'm sad to say I proved them correct at my latest range day. No major damage, but it put a quick end to the day of load development.
With the next step up in charge level, two rounds fired of the 10 round set I had a primer blow out. It blew the firing pin totally out of the bolt carrier. The firing pin found its way below the bolt and protruding into the magazine well as can be seen here.
In the photo below the case on the left shows the primer is still intact, the concave area from the fire pin hit. The one on the right you can see it was totally punch threw and the concave part is flipped and facing into the case. This allowed enough pressure to bleed back to blow the firing pin clear past the retaining pin shown. I'm going to install one of the solid type firing pin retainers and I will no longer use the Sellier & Bellot 5.3 LR for .308 Win.
As far as the charge level, this was well within the published data. The round that caused this recorded 2675 fps of the Match King HPBT 175 gr bullet. Also, the red around the primer is from a Sharpie. I use them to identify the load.
Sellier & Bellot Primer use chart:
With the next step up in charge level, two rounds fired of the 10 round set I had a primer blow out. It blew the firing pin totally out of the bolt carrier. The firing pin found its way below the bolt and protruding into the magazine well as can be seen here.
In the photo below the case on the left shows the primer is still intact, the concave area from the fire pin hit. The one on the right you can see it was totally punch threw and the concave part is flipped and facing into the case. This allowed enough pressure to bleed back to blow the firing pin clear past the retaining pin shown. I'm going to install one of the solid type firing pin retainers and I will no longer use the Sellier & Bellot 5.3 LR for .308 Win.
As far as the charge level, this was well within the published data. The round that caused this recorded 2675 fps of the Match King HPBT 175 gr bullet. Also, the red around the primer is from a Sharpie. I use them to identify the load.
Sellier & Bellot Primer use chart: