What to do about this crown?

[Claven2]

the pads are both soldered and screwed. Normally you would snug the screws, then heat the pad until the solder flows (it's just lead solder), and as you play the torch over the pad (a second set of hands helps), you tighten the screw to further bed the pad in the liquid solder. If the solder is a good joint, then the screws would never loosen - even if not freshly staked.

your rifle looks like the solder coverage is only maybe 60%. I would re-tin the receiver (and maybe the pad) before re-affixing it.