I have been having some trouble regarding misfires in my 300 win mag reloads. I'm getting a nice clean dent in the primer but no bang. If I try the round 3-4 times it will go off ok. In an attempt to sort out the issue I primed 10 cases and measured the primer depth (all were carefully primed so that they were flush with the bottom of the case)

So the 10 primed cases all fired 1st time so I'm thinking that the primer depth may be the route cause of the misfires. So the question is how far below flush with the bottom of the case is acceptable? For information I am using a rcbs hand primer.

Thanks