The good, the bad, the ugly

The last few times I used my AR it would occasionally “double”. I thought maybe it was just dirty and cleaned it. It didn’t do it for a while then it did it again. I cleaned it then when I had the private party last month it did it when it only had a few rounds after being cleaned. I set the gun aside and used a different one.

About three weeks ago I removed the trigger group and was going to replace the springs. That surely was the problem, right?

I was dismayed at the state of the important surfaces.

This is a known good hammer and trigger:


And cropped down to just the interesting parts:


This is the bad hammer and trigger:


Again, cropped to just the interesting parts:


Do you see the difference? That’s some ugly wear on those critical surfaces. I believe that was the source of the problem.

It would have been really ugly if the ATF took a dislike to me. A gun malfunctioning like that can result in a prison sentence. It’s not right. The law should be fixed. The ATF should abolished or at least have it’s “claws trimmed”. But that is the way it is.

I’m pretty sure the known good trigger group parts fixed the problem. I have probably 300 rounds through it without issue now.


24 thoughts on “The good, the bad, the ugly

  1. I wonder if that’s a sign of incorrect heat treatment of those parts.

  2. every few hundred rounds perform this function check.

    Place selector on SEMI
    With Trigger pulled to rear, pull Charging Handle and release.
    SLOWLY (as in 1/4 the speed of normal) release Trigger.
    Hammer should not fall, should release from disconnector and should ‘catch’ on trigger. You should hear a ‘click’ but this is the sound of the Hammer being caught by the trigger.

    Pull Charging Handle to rear and keep it pulled to rear
    Pull Trigger to rear and while keeping trigger pulled to rear, release Charging Handle.
    Repeat the SLOW Trigger release.
    Repeat this three more times.

    The Hammer must hold without falling for five times in a row while the Trigger is being slowly released.

    This is a modified and truncated version of the PMCS check that Uncle requires Armorers to perform at least every 90 days.

  3. Heat treatment was my thought too. The Guncounter forum had a thread on magazine springs, and the upshot was that good springs shouldn’t take a set, you should therefore be able to store them full, but the only way to tell if the spring was good (properly heat treated) was to store them full-up.

    As for the ATF, when the gun design is noted for doubling when dirty, it is bad logic and law to jump to the conclusion that you have designed it to be full auto. When defective parts can cause the malfunction, what the ATF is doing is what Doctors refer to as thinking of Zebras when making a diagnosis. (when you hear hoofbeats, don’t think of Zebras). What the ATF has done with these doubling incidents is not merely to think of Zebras, but to think of Blue Wildebeest, an even rarer hoofed animal.

    • Good point on springs. One way to look at it: consider the springs on your car. Those don’t acquire a set over the life of the car, and they work much harder than your magazine springs.

    • “As for the ATF, when the gun design is noted for doubling when dirty, it is bad logic and law to jump to the conclusion that you have designed it to be full auto.”

      Don’t forget the whole “easily restorable to full-auto” clause written into the law. If a wear pattern conducive to doubling can be simulated by a few minutes with a diamond file (which I suspect it could), then the entire AR-pattern design can be deemed “easily restorable” by the ATF-FTB, and therefore subject to NFA provisions and/or wholesale bans.

        • Give them ideas…. and let the lawsuits drive them into oblivion.

          • Exactly — the precedent that got set when they had their asses handed to them by Vollmer over some HK receiver conversions that were then re-converted back to “semi” conversion will kill them. As the courts said of the HKs, it was bizarre beyond belief to posit (as the ATF was trying) that, under the ATF’s own position that the ATF authorized the illegal importation of tens of thousands of unregistered “machineguns” (because ALL the semiauto HK rifles imported by that time had receivers that were mechanically identical to the ones ATF was insisting were still “machineguns”).

            “OK, ATF, you’ve authorized the unregistered sale of HOW MANY ‘machineguns’ since the semi auto AR15 was first introduced on the American market? Nope — your assertion that the AR15 is readily converted because it CAN wear out, like ALL semiauto designs, to the point of firing fully automatically. Your position leads inexoriably to an absurd position, so as in Vollmer v. Higgins, YOU LOSE, on the same exact grounds.”

            (And don’t try to counter with Olafson — different issue entirely, in that he admnitted to teh ATF he had the skills and knowledge to convert an AR15 to full auto, and his rifle was siezed – with NO broken or excessively worn parts, with a combination of parts NEVER used by the OEM – in a configuration that allowed fully automatic function when the gun was fed with the ammunition it was actually chambered for (at the time of its production, ALL Olympic rifles had SAAMI .223 Remington chambers, NOT milspec 5.56mm chambers — so using civilian SAAMI aamunition with civilian grade primers, rather than the deliberately harder milspec primers, was fair game for ATF.)

            Keep in mind that a pistol like the 1911 is EVEN EASIER to cause a runaway malfunction, as anyone who has worked a range and seen your typical “home trigger job” can testify.

  4. And thus the reason I’ve gone to CMC triggers in most of my rifles. (I have one with a National Match Geissele trigger, and a couple with Alexander Arms Tactical triggers which will be replaced for free if they double or wear).

    CMC triggers are drop in replacements, and if you can find a better trigger for the price, buy it. I haven’t. Endorsed and used by Pat Kelley, which is good enough for me!

    • Do you have an opinion on Timney triggers for AR’s? They are about the same price as CMC.

      • Timney triggers are well built, but I’ve had one in an AR fail, and one in my bolt gun bind, so I’ve shied away in recent years. Both my have been statistical abnormalities, but when Pat Kelley showed me his experience with CMC’s, and seeing the volume he shoots, I made the switch and have been very happy. Even my .22 AR has one now.

      • Honestly, the only replacement triggers I would trust on a “serious social purposes” would be Gissele (including the ALGs), because of the combined factors of durability, reliability, quality, and cost — the other replacement triggers just don’t offer enough bang for the buck to make it worthwhile buying them over standard.

        Having said that, I would trust a CMC trigger over a Timney, if failure resistance was a significant factor, only becuase Timney has always focussed on precision to the exclusion of everything else except safety. CMC doesn’t seem to be as specialized, and is seemingly “tougher” than Timney, even if the Timneys are generally “better” triggers.


  5. Bad steel or bad heat treat or a combination. How many rounds on that trigger?

  6. You could try a file test. Run a good file on it. If it bites in, that would be a failure to harden properly. If it skitters across the surface, then you may have a mechanical problem. Failure to harden correctly is the most likely issue. There could be some sort of clearance or dimensional problem. Or a combination, which is always fun to sort out 🙂
    Easiest thing is to just keep a close eye on those surfaces. Problem is, sometimes that sort of failure mode only becomes obvious to the unaided eye long after the initiation of the actual damage, and the visual failure sequence can be very rapid once it reaches that stage.
    In addition to Miles’ suggestion, I would add a visual inspection w/ optics after every range session, or ten mags, whichever comes first. An OptiVisor is very handy for this sort of thing. Or use your camera if it has a closeup-zoom capability that is easy to do in the field.
    If you have another AR with lots of rounds through it, do an exam of the relevant surfaces so you will know what you should be seeing.

    • All good advice. Another bit of good advice: the military buys firearms parts that are made to certain standards. Everything from the dimensions to the surface finish to the heat treatment to the alloy to the manufacturing methods is rigidly defined, and the specification data for a simple-looking part can fill a fat book.

      The guys selling AR parts in brown paper bags at the gun show may have merchandise that is of equivalent quality and durability to milspec. Or maybe they’re selling parts made in China out of waste bits and scrap metal from a nail factory. That email from a middleman about a big batch of AR parts they’ve found a great deal on may be letting you in on a great bargain. Or not. Let the buyer beware.

      …oh. My personal AR (yes, I have one) has an ALG Defense “enhanced” trigger, which is made by Geissele, a company with a very good reputation. I’ve only put a few hundred rounds through it so far, but so far there are no problems and I can see no unusual wear.

  7. I have four AR pattern rifles, three 556’s and one 308. I put Wilson Combat 3 gun trigger assemblies in all of them the day I got them and have never looked back. The hardening of the parts is through the entire piece, and they come in a hardened frame that mounts as one part, taking the wear out of the holes in the frame of the gun. I will start to take a good look at the trigger assemblies I took out of these to see if I can figure anything out on them.. be back shortly.

  8. Hm, I just got a popup ad. What gives? I didn’t think this site had such crud. Ads on the side are fine; popup ads are not.
    FWIW, error 503 is still with us.

    • Popup ads are not anything I authorized. Whose ad was it? I’ll get rid of it.

      Yeah. I know the 503s are still here. I’m going to give the hosting provider one last chance then I’m moving elsewhere.

      • Sorry, I don’t remember the ad. And it was the only time I’ve seen this. It’s possible my finger slipped and I clicked an ad. Assume for now it was a false alarm; if I see it again and it looks like it was not an operator error, I’ll note down the details and let you know.

Comments are closed.