Misfires!

[climbhigher]

I was helping a buddy find a load for his new 30-06 (Savage Axis) the other day. When we got to the range, 1 out of three rounds misfired. I have been raking my brain trying to figure out what went wrong but I am at a loss. I am sure it was not the primers because I used the same batch in my reloads and had no problems. There is firing pin marks on the primers themselves, however they appear to be very light strikes. The firing pin appears to be coming out far enough, so I don't think that is the problem. I took his bolt out and cleaned it, I thought maybe there was some grease in there and the cold temps were causing the pin to stick, but that did nothing either.
One thing of note is that we broke in the barrel with a box of factory ammo. Two of the rounds popped primers! I have never had over pressure signs on factory loads before. The only thing I can guess at is that there is too much play in the chamber itself?
Any ideas?

 

[Ganderite]

I ran into misfires once because the brass was a bit small/chamber a bit big and the bullets were seated out enough to touch the rifling.

This meant the case shoulder was being held off the chamber shoulder. When the firing pin hit the primer, it pushed the bullet farther into the rifling, which softened the blow.

See if once fired, neck sized bras fires with the bullets well off the rifling.