I've been reloading since the '70s but am new to 300 BLK.
I had worked up loads for a 130gr OTFB Pulled bullet (from American Reloading) and H110 using Hodgdon data which lists a "starting load" @ 17.1grs with a "maximum load" @18.6grs. The brass was new Starline.
Starting with the "starting load" all went as expected until the second shot with 18.5grs of H110 when the primer popped out (velocity was as expected from the loading data). I fired the remaining 8 rounds without incident.
All charges were thrown and weighed to within +/- 0.02grs with extra care as I was working up the load.
No problem since I had found the most accurate loading was lower at 18.3grs.
What surprised me was that the primer pocket expanded to the point that a new primer justs falls in and out of the pocket. That's a new one to me. Anyone else have a pocket diameter expanded or have any thoughts on why this would happen on a single round with no obvious signs of overpressure on the other 9 rounds of the same load?
I had worked up loads for a 130gr OTFB Pulled bullet (from American Reloading) and H110 using Hodgdon data which lists a "starting load" @ 17.1grs with a "maximum load" @18.6grs. The brass was new Starline.
Starting with the "starting load" all went as expected until the second shot with 18.5grs of H110 when the primer popped out (velocity was as expected from the loading data). I fired the remaining 8 rounds without incident.
All charges were thrown and weighed to within +/- 0.02grs with extra care as I was working up the load.
No problem since I had found the most accurate loading was lower at 18.3grs.
What surprised me was that the primer pocket expanded to the point that a new primer justs falls in and out of the pocket. That's a new one to me. Anyone else have a pocket diameter expanded or have any thoughts on why this would happen on a single round with no obvious signs of overpressure on the other 9 rounds of the same load?