[Unclenick]

None. Prudence says, never shoot someone else's reloads. Pull them with an inertial puller to preserve the components and reload them.

When bullets are seated too deeply into the case it raises pressure. How much depends on the powder, primer, and gun chamber geometry. A lead ring around a cartridge and up in the seating die is likely due to not flaring the case mouths adequately, then having the case mouth shave lead off. You can remove it with a plastic toothpick, usually, or else remove the seater stem from the die and clean it off outside.