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Last year, I had a bulb that burned out in my right rear tail light. I found that out when I got pulled over by the Johnson City PD. When I made it out to the ranch, I discovered that the head of one of the Phillips screws holding the lens in place was completely stripped. If you do any work at all on your guns, you’ve surely had a similar issue. Usually it’s some infinitesimally small Allen head screw. You strip it, curse loudly, and then try to figure out a way 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 specialized for 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. The set I have isn’t for sale online, but there’s a 10 piece set that includes five drill bits and five screw extractors. They sat largely unused in my toolbox until Tuesday night. Whilst removing a MegaFins rail from my AR in favor of a new rail I’m testing (hint: it’s from a company known for triggers), I stripped one of the Allen head screws. I snagged by bit set, selected the proper bit, and just like my father before me, extracted the ruined screw. The machinists and gunsmiths that frequent TTAG will probably laugh at my ignorance of left hand drill bits, but I was blown away at how well they worked at screw extraction.

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.

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  1. Who ‘needs’ a set of left hand drill bits for recreational shooting?
    Nice tip though. Some of the newer screw designs (torx) can be manipulated with the wrong size driver, but are extremely prone to stripping. Maybe it’s just user error but I never had that problem with philips or hex screws.

  2. Screw extractors (also known as E-Z Outs) absolutely come in handy from time to time when threaded fastner heads become stripped or break off. Make sure your power drill has the torque to do the job; a cordless, battery operated 3/8 inch power dill may not be up to the task.

    Also a drop or two of Loctite is useful for fasteners that won’t stay tight. Red, or Blue Loctite depending how much grip is necessary to secure the threaded puppy down given the circumstances of fit and concussion the weapon is subject to.

    • Before using the E-Z Out, one must usually drill a mall pilot hole into the top of the defective or broken fastener screw (with a smaller standard clockwise turning drill bit) in order for the E-Z Out to ‘bite’ the broken fastener with adequate grip to back out the threads.

      • This is another place where the left handed bits shine. As they also drill holes you can use one to drill the hole for the extractor. As often as not, the screw will back out during this process, negating the need for the extractor. If it doesn’t back out, you have the hole drilled and can continue to use the extractor as planned.

    • Just be careful with loctite in high temperature areas. Above 300 degrees F or so, loctite re-liquifies, and has a really slippery lubricant property.So, you guys who think you are securing your can mounts with loctite, make sure the threads aren’t backing out!

      • I use CAT(diesel trucks?) high temp lock-tite that I get from a buddy.

        It also helps at times to take the point of a soldering gun(trigger type) and heat up the screw at the first sign of a problem. Sometimes it will come right out.

      • Yep, thanks for the cautionary note.

        One should still always monitor the mechanics and function of ones firearm or other equipment, even if there has been no previous performance or failure issue.

        Experience teaches; sometimes a quick fix…isn’t.

    • I’m a big fan of HF tools for things I use occasionally or when I can roll the dice on quality.

      Getting a cheap easy out is NOT a good idea because if it breaks, its damn near impossible to drill them out, since they are usually hardened.

      So while most of my hand tools are Craftsman, my ezOuts are Snap-On


      • So much this. I once broke a easy out off in a thermostat bolt for a Pontiac Tri Power manifold. That was a costly mistake.

      • When you run into situations where you’ve buried a hardened steel tool into someplace where you want it to not be, the solution is sometimes to anneal the broken tool in place.

        Get an oxy/acetylene torch and a fine tip, then get the broken tool bright red-hot, then allow it to cool slowly. You’ll be able to drill or machine it out.

    • One of the single largest contributing factors to screws being buggered up is cheap tools.

      When I go in/out of a gun, my ultimate goal is that, aside from whatever malfunction you complained about is fixed, you see no evidence that someone has been into the gun.

      The way I know some amateur has been into a gun is that they used cheap tools on the gun, and they left marks and tracks. Stripped screw heads (slotted or allen heads) are usually munged up by using a cheap screwdriver or wrench, that doesn’t fit well, and wasn’t used with proper skill.

      The #1 way I make sure that I leave no tracks is to use high quality tools that fit. If I can’t find them, I make them. I make screwdrivers for specific purposes on guns all the time. Same deal with punches, helper pins, various hooks and widgets for positioning springs, etc.

      I used to buy Horror Freight tools when I needed a tool “now” and I need it only once. If I need a tool for long-term, even if infrequent use, and/or the consequences of the tool failing to work perfectly are high, then I buy or make quality.

      • I’m with you on the “don’t buy cheap tools” advice, but I submit that the larger factor with stripped hex screws is the introduction of metric sized screws and allen wrenches to the U.S.

        SAE sized allen wrenches would usually either fit or they would be small enough to turn inside the screw without damage. But slip an SAE wrench into a metric screw, or vice-versa, and it could be just small enough to round off the screw.

      • @ DG – Any recommendations on a gunsmith screwdriver bit set like Brownell’s?

        How’s this one?–prod417.aspx

        I try to buy quality when buying tools, but as others have noted, if you’re gonna use it once Harbor Freight has gotten my business on few of my tools.

        Proper driver tools on guns I have heard is simply required if you don’t want buggered screws on your guns.

        • The Brownells sets are very good. I’ve used those, the Forester sets and the Wheeler sets. I think the Brownells is the best, but it also is missing some of the bits that the Wheeler big set has.

    • I love Harbor Freight.

      And there’s nothing wrong with their easy out kits. If they can remove a broken crank pulley bolt on my old Honda without breaking, I’m sure they’ll be just fine for use on your firearms.

      Nothing wrong with being overly cautious with tool selection but its been my unfortunate luck to own a series of really crummy cars (until my current vehicle, knock on wood). So I have some experience with Harbor Freight.

      I’ve never had any problems with any of the tools I buy from them as far as catastrophic failures (breaking, bending, etc.,) Now buying the wrong tools for the job… Well, that’s happened on “accident” ;-).

      Oh well, just expands my collection haha

      But on a serious note, stay away from Harbor Freight during a sidewalk sale. Just too many fun toys you didn’t know you needed to walk out of there with that ONE thing you came in to get. True story 🙂

  3. Ah young man, you will gain much knowledge about tools as you get older. Some tools you may use less than once a year, but they are worth twice what you paid for them in saved aggravation. And you may find yourself making your own tools to solve “special” problems. Have you ever seen some of the weird bent wrenches in car mechanic tool catalogs? Some guy 50 years ago took a torch and bent a wrench to fit and it was so handy that others copied it until it became a catalog item.

  4. To the aspiring chef side.

    I’ve had friends bring dinner ingredients, to see what I would come up with. Kinda like secret ingredients on Iron Chef.

    It was fun and many great conversations were had and wine/beer was drunk.

  5. Part of the fun of work such as this is to screw up and then find something to “”””rig it, cursing and throwing crap all over the place while “fixing” it… at least that’s what I learned from my father…

  6. A good way to avoid stripping stuck screws in the first place is to chuck an appropriate driver into a (unplugged) drill press, line up the part on the table and clamp it down if appropriate, and use a correctly sized rod to turn the chuck while applying down pressure with the press. I learned that one in gunsmithing school, and it’s saved me a lot of trouble over the years.

  7. I’m a rep for Forney Industries (welding supplies, work gloves, etc). Many of the stores which carry our products will have a display of left handed drill bits which can be purchased singly- and often a display of easy-outs right beside it. If they aren’t carrying it, they can certainly get it for you.

    • Bump for Forney products they have managed to maintain their quality over the years and haven’t sold out.
      I’d like to think of myself as a pro like so many other products Horror Freight quality has declined over the years don’t even try their drill bits as the points are usually off-center good for maybe a single hole.
      Drill bits come in all quality I bought the best I could afford and NEVER loan them out. I keep mine separate and use only when necessary I have a machinest friend whom I use for any problems good fixtures a lathe and a small mill make a huge difference in the outcome. The slide on a 1911 gets pretty expensice when you need a new one from idiots who just keep making bigger holes!

  8. This has been thoroughly hashes out in the comments, but as a machinist by trade, I’ll throw in my +1 for left-hand drill bits. Nothing worse than spending a few hours on a part only to have an overzealous engineer over-torque a tiny screw and blow out the hex.

    We’ve also used a heavy duty DC power supply to “weld” the small allen key into the mangled hex of the screw and work it out that way. Obviously that’s a technique that involves some more expensive equipment. And a disposable supply of allen keys in many sizes.

  9. LH bits are definitely a big help for removing stuck fasteners. One tip that sometimes works for damaged Allen heads is to force a Torx driver into the screw since the sharp edges of the Torx will bite into the screw and give you enough grip to back it out. Another good trick for loose fitting Allen heads is to use a “wrong” sized hex key to get a tighter fit. When I worked on power tools we used to use 1/8″ hex keys to deal with stubborn 3mm Allen heads because the 1/8″ was a very tight fit and wouldn’t slip and round out the screw head.

  10. make sure you mark or identify your left handed drills indelibly and store separate from your right handed ones
    some other good approaches to a stripped hex or torx flathead socket capscrew removal are
    1) always (always!) marinate it in penetrating oil, i prefer kroil, shocking it regularly with a hammer, for up to several days before messing with if possible;
    2) put a correct sized driver bit, cut off allen wrench, screwdriver, etc. as appropriate, in the recess and, with the workpiece firmly supported on a durable non marring surface, with the screw straight up, strike the driver sharply with a hard faced medium size hammer. this is a good technique to shock kroil(always) into the screw and frequently results in the screw becoming removable. if you have help, have one put down pressure and out torque on the driver bit while the other smacks it with the hammer. this often results in the screw breaking free explosively, so have a plan for where all that nasty hard metal is gonna go relative to the expensive shiny parts. duct tape works.
    3) for a flathead screw get a flat tip punch or dowel pin slightly smaller in diameter than the head of the screw, put the workpiece on a non marring durable surface with the screw of interest straight up, and, holding the punch down firmly, centered on the screw, and vertical, smack it sharply with a hard faced, medium weight hammer. repeat up to several times with increasing odds for success. this will have two good effects: the shock will break adhesion between the screws threads and head and the hole, freeing it or allowing penetrant in (always); and any hex or torx recess material which was buggered up will be swaged back into the hole, allowing an on size driver bit to be driven into the recess reshaping it and often allowing removal. this works somewhat less well on button head screws, need to be more gentle, and mainly expect to swage down the recess. obviously be aware of where the hammer and punch are going to go after you hit the punch(HIT the punch!)
    4) scorched earth approaches: flat head-use a tap sized drill(right or left hand) to carefully drill down through the recess and into the screw til the head separates from the shank of the screw. button head or hex head- carefully grind away the head until you see it turn blue from the heat, at which point it is so thin a little gentle brutality will separate it from the shank. hopefully this will allow disassembly, or at least drilling for an ez out. the left handed bits really shine for drilling for the ez out. always drill all the way through the screw if possible, they usually grab and extract on breaking through.
    too long no doubt, but not so as not to point out, hopefully unnecessarily, that everything ive mentioned along with everything else ive read in this article and comments demands safety glasses


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