SAMMI spec for Large rifle primer pockets are .125 to .132 and you want the primer to be below flush .003-.005 so .131 or so. Get a good primer pocket uniformer to prep the primer pocket each time you load the cartridge case ( new to discard) that will remove material ONLY from the bottom of the primer pocket. Most are preset to the maximum dimension + or - .001- .0015 or so. Sinclair sells a carbide version along with an adaptor so you can use it with an electric screwdriver that works very well. Be sure to use a good Priming tool that will let you "feel" the anvil just touch the bottom of the primer pocket so you dont crush the primer and affect ignition.
Actually, primers are supposed to be seated with 2-3thou of crush (preload), but most people don't measure it.
With that & knowing .128 primer height, you'd be seated ~.125 off the pocket, and any amount of casehead above this is sufficient.