We were shooting the first loads thru my sons 10 in. Hornet barrel and it burned holes in the edge of the primers on two different loads [pin sized holes]. Both loads were middle of the spread. 50 gr sp with 11 gr. Lil Gun and a 40 gr sp. with 12 gr. Lil Gun. He was using small pistol primers.Book calls for small rifle I know but some data lists small pistol also. So thinner cup on the small pistol primer the culprit? We will rerun the tests with CCI small rifle primers as soon as possible.

I had a savage 22 hornet that I shot a fair amount more of little gun than 12 grs and I used small rifle primers in it with excellent accuracy but I believe the speer book calls for small pistol primers,I cant chk since my son has the book.I was using 40 gr nosler bt and had no problem.

Interested to see whether changing to rifle primers fixes the issue.

These were an older lot of primers and my son said when de primed the brass the de capping pin pierced several primers. So leads me to believe thin, soft primer cups.He has reloaded them with small rifle primers so we will see.He said all the burned thru pierced primers had just the one small hole burned in the edge.