Commercial primers are constructed with the anvil sitting about 0.005" proud of the primer cup. When installed the anvil is pressed flush with the cup in "reconsolidation". This preloads and 'arms' the completely hardened primer compound to ensure firing.
The videos and posts I've seen press the anvil into the wet compound flush with the top of the cup. Could this be a reason for reliability issues? Has anybody tested this in their homemade primers?