Took my 300 wsm to the range. Sight in check. Had 3 rounds of Fed fusion ammo from over a year ago, and then a new box of the same, bought this past winter/spring some time.
Check this pic:
The 3 on the left are the old box, on the right is the new ammo. 2 of the primers completely came out and the 3rd leaked gas. I'm assuming this is an ammo problem. I have another box of fusion ammo purchased at the same time and place as the one blowing primers. Somewhat reluctant to try any more. The bolt was hard to open after each shot..............like the ammo is on the HOT side.
Bought another box of different 300wsm today but likely won't get to the range till next week.