Also, do you mean "strip the screw" as in the threads outside or the
screw head or the screw threads? because I suspect its the outside
threads that are stripping.. the stuff outside looks like soft plastic
(which will strip..) and the inside metal could be overdrilled.. not
sure what you're doing but standard zinc ones should hold (at least
just by hand-tighetening)

It's the threads of the screw that stripped off (worn down)