08-25-2023, 08:01 PM
dsb,
Along with checking those measurements as Montana has prescribed can you tell us your load please. I ask this because there is cratering in some of the primers that have not pierced. Flattened, pierced, and cratered primers are classic symptoms of over-pressure. The unusual aspect here is the pierced primer in the Hornady factory ammo. Factory ammo should not be over-pressure, unless something else has caused the pressure to display at the primer.
Changing out the gas system is unlikely to help as the damage on show is caused before the bullet reaches the gas port. Whatever is causing this can also occur in bolt guns.
Along with checking those measurements as Montana has prescribed can you tell us your load please. I ask this because there is cratering in some of the primers that have not pierced. Flattened, pierced, and cratered primers are classic symptoms of over-pressure. The unusual aspect here is the pierced primer in the Hornady factory ammo. Factory ammo should not be over-pressure, unless something else has caused the pressure to display at the primer.
Changing out the gas system is unlikely to help as the damage on show is caused before the bullet reaches the gas port. Whatever is causing this can also occur in bolt guns.