I was once stopped by a cop on my way to the ranch because of burnt out tail light. When I made it out to the ranch, I discovered that the head of one of the Phillips screws that holds the lens in place was completely stripped.
If you do any work at all on your guns, you’ve surely run into this problem. It’s some infinitesimally small Allen head screw. You strip it, curse loudly, and then try to figure out how to get it out.
My dad was an automotive mechanic for the better part of three decades and has amassed a large Snap-on toolbox full of various tools. Many of them are specialized to do a single job.
He saw my tail light predicament and headed over to his large chest of tools and returned with a drill bit. He chucked it in a cordless drill and slowly started turning it counter-clockwise. Like magic, the screw backed out.
My dad smiled, returned the bit and drill to his toolbox, and poured himself a cold drink.
A few weeks later, he came to Austin to visit and handed me a Matco 5-piece left hand bit set (there are more affordable options out there). They sat unused in my toolbox until recently. While removing a rail from my AR in favor of a new one I’m testing, I stripped one of the Allen head screws.
I snagged my bit set, selected the proper bit, and — just like my father before me — easily extracted the ruined screw.
The machinists and gunsmiths who frequent TTAG will probably laugh at my ignorance of left hand drill bits (or extractor sets), but I was blown away at how well they worked at screw extraction (Brownells has a handy set).
I’m not necessarily saying you need a set of left hand bits, but if you’re as prone to destruction as I am, it certainly can’t hurt to keep them around. You’ll rarely use them, but when you need them, you’ll be really pleased you have them on hand.