Primer problems, No fire in 7mm RM

[Bullet bumper]

What can also happen with a primer that is not seated down correctly is that even if the primer cup does not move with the firing pin strike , the Anvil can still move away from the Priming Compound as the cup is being dented because the anvil is not close to the base of the pocket . Thereby not giving any real "Pinch " to the Priming Compound . In this case the primer cup can look well dented but still have inconsistent ignition or even misfires.
If the gun works fine with factory ammo then it's unlikely to be anything wrong with it .