doubt you will have much luck trying to drill the insert out BSA 500, probably too hard and if you get offline you'll take out metal you will need.
If you can prize up the top thread and get hold of it with pliers it should twist out, then put a new insert in ( maybe run the tap through it first, but lightly).
No harm putting a bit of loctite in with the insert.
I've used helicoils with great sucsess others prefer different types