I just melted holes in several bottles using a microwave oven. All of them cracked (even shattered) within a couple of minutes of cooling. The glass shrinks upon cooling and the internal stresses are too much for it. For normal bottle-glass, to avoid cracking you’d have to treat the bottle in a glassblower’s annealing oven after melting a hole in the side. That, or use a Pyrex bottle. Pyrex shrinks so little upon cooling that it usually needs no annealing. I’d stick with the copper tube, drill press, and wet sapphire paste.