I have a few unsightly bronze screws that were not countersunk enough to bung. So I'm wondering if, since bronze is soft, can I drill them down a bit, say a quarter inch or so, and epoxy bungs in? Its an epoxy plywood boat, this will have no structural effect what so ever. Purely aesthetic. I know the bungs will look better than the screw heads showing. I mostly want to know what drill bit I might buy and if it will stay sharp enough.