I don't know anything about shiny swapping, but if you want to chain-hunt, a good strategy could be:
Smeargle @ leppa berry
Ability: Technician
EVs: who cares?
- Damaging Ghost-type move
- Conversion
- False Swipe
- Recycle
the ghost-type move is to get rid of regular Beldums, Conversion will change smeargle into a ghost type because its first moveslot is a ghost-type attack (immune to take down; no recoil for beldum), False Swipe is obvious, and Recycle for INFINITE PP!