In my never ending quest to use a cast boolit in my 30-06 I seem to have encountered another stumbling block. First the specifics:
Rifle: Rem 700
Caliber: 30-06
Brass: LC of varying dates
Boolit: Lyman 311291
COL: 3.115"
Powder: Accurate 5744
Load: 20.8 grains
Primers: Rem LR
Previously I had been using a heavier load (published by Accurate) of between 24.0 and 28 if I recall. The result of that experiment was the primers were flattening and backing out even at the min load of 24.0.
Anyway long story short. I loaded up ten rounds of LC brass at a COL of 3.115" where I had used a COL of 3.0" previously. The reason I did this was that accuracy was atrocious with the previous load along with the primer distortion. The chamber actually could have taken a COL a few thousands longer but I decided that I would at least go slowly before I ventured that close to the lands.
I took these to the range today, not caring really what the results of my shooting skills were, but to see how these reduced loads shot. The results are interesting. The loads were mild, very mild. So mild that I wished I had brought along my chrony to see what they were doing. I wasn't pleased with the performance of the load but the biggest surprise was when I examined the shot brass. The primers are bulging! My question: What could cause the primers to bulge? It sure wasn't the pressure generated by the load.