When you are finished and re-assemble, also take care. Start the screw with your fingers and run it in as far as you can with finger pressure. Tighten with the screwdriver. When you feel the screw getting tight, the tang should be flush with the wood. As you do the final tightening bring the slot in line with the long axis of the gun (indexing the screw) and stop there
It should look like this (borrowed off the grades tab)
