Yep, Its Legal & Available: Fire On Pull & Release Triggers

In yet another “I can’t believe its legal” installment from the ATF Technology’s branch, two companies are approaching the market with fire on pull and release trigger systems. Fostech Outdoors (known for their Origin 12 shotgun) and Franklin Armory (for the .17 semi-auto modern sporting rifle) are both readying “binary” (as Franklin Armory is calling it) trigger systems for the general market.

Both companies offerings have been approved by the ATF for meeting the definition of “semi-automatic” despite having two shots per “pull” (at least in the conventional sense) of the trigger. To meet the ATF’s requirement, specific movement is required to release both shots and the cycle can be broken by switching the trigger packs back to semi-auto.

Military Arms Channel was able to get its hands on Franklin Armory’s offering, The Binary Firing System. The system is perfectly functional, but ran into Mac’s uber-fast trigger finger out-running the bolt going home on the release side of the firing sequence. Dissapointing, as I would hope Franklin could figure out a way to use an M16 carrier to trip a sear allowing the shooter to release the shot only after the bolt goes into battery.

Fostech’s trigger, The ECHO, will be available for demonstration at SHOTShow. Representatives have confirmed it will be available for shooting at a private event Thursday night. TFB will be coverage at the event and you can bet we’ll be making a bee-line to Fostech to put the booger-switch through its paces.


Nathan S

One of TFB’s resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR’s, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.

The above post is my opinion and does not reflect the views of any company or organization.


  • Ken

    A sear that only allows the hammer to drop when the bolt is fully in battery is called an auto sear. If that were the case and you got rid of the disconnectors or disengaged them both, then it would be full auto.

    However, certain semi auto firearms do have a “safety sear,” such as the Zastava M76, PSL, and even the common SKS. The PSL and M76 however, got rid of the third pin and safety sear for US import since it’s an AK style receiver with what can be construed as an auto sear. All SKS’ have a safety sear, and it has lent itself easily to both illegal and legal full auto conversions.

  • Tom

    I am sure that very soon whoever it was at the BATFE that approved these will get a swift smack to the head and the decision will be reversed.

    • Edward Franklin

      They’d probably have to drag him out of retirement to do that, this ruling was first made probably two decades ago on the Mini-14. You can jam a staple in their FCG and achieve the same result.

      • Ken

        The beauty of it is that you can do the same thing with an AK or AR by sticking a spacer under the disconnector made from a staple or soda can.

    • Anomanom

      Probably more like a double tap to the head, but yes, i agree. Although, this would be a nice addition to that double pump action shotgun the D-12 or whatever it is.

      • iksnilol

        Tape the triggers together and enjoy your supershotgun.

        • Phaideaux

          The dp12 uses a single mechanical trigger .

          • iksnilol

            Crap, forgot about that.

            Okay, two regular shotties + duct tape and we can live the supershotgun dream.

          • Anonymoose

            Needs moar 1740.

          • Cymond
    • Nicholas Chen

      I don’t know. Release triggers are used in skeet and trap. Since that is legal it makes sense that pull and release are there fore two different actions.

      • Tom

        Its the government they do not need to make sense or be consistent. Its one thing in a skeet gun but putting something like this in an evil AR15 is another matter entirely.

        • De Facto

          Sadly, I have to agree with Tom. It may cause the BATFE to reverse their decision on release triggers entirely. The downside of allowing an agency to create and enforce it’s own regulations(laws).

        • The Brigadier

          Go to Tac-Con and check their’s out for an AR.

      • Sianmink

        Pull/Release and Release/Pull double triggers have existed in skeet and trap for decades.

      • Ken

        But ARs are black and scary, and we all know how that goes.

    • hydepark

      I just LOVE the fact that this is coming out after all the Progressives thought they were getting their big EO win last week. Hopefully they see this and gnash their teeth and realize we aren’t giving up on this whole rights thing after all.

      And by the way, I keep hearing people say we should have guns for sport. I like this idea and I think it speaks to repealing the machine gun ban. I have a right to own and use newly manufactured machine guns for legal sporting purposes. Any thoughts?

      • Budogunner

        Sub-gun competitions would be pretty awesome. I could see those getting good reasons on television if handled well, like the MUCH more dangerous Red Bull Air Races.

        • RickOAA .

          There have been sub gun competitions for some time, you’re just probably never going to see such a thing on network TV.

      • RickOAA .

        We do have plenty guns for sport and defense. The problem is that some are regulated by arbitrary laws.

        Our great leaders are only concerned that we own guns and ammunition for hunting deer.

  • This seems unsafe.

    • JumpIf NotZero

      That’s because it is.

      Legal and good idea are mutually exclusive in this case.

    • Joshua

      It is unsafe.

    • Andrew

      Better hope you never have a squib…

      • Sianmink

        It’s no more dangerous than a squib with any other trigger system.

    • Phaideaux

      I fail to see how exactly, as long as whoever is using the trigger is aware of how it works. As far as squibs being a problem, its no more of a problem than in an auto, and nobody complains about those. Its not likely to cycle the action anyway.

      • iksnilol

        Uh, it isn’t rare for a squib to cycle the action.

        • Phaideaux

          I can grant you that every single squib ever will cycle an action and the conclusion that these triggers are unsafe still doesn’t follow. Autimatic firearms would exhibit the same problem, but nobody treats those like ticking time bombs.

          • Evan

            The difference is that automatic firearms STOP shooting when you release the trigger. This one fires a shot when you release it. I can understand the concern,

          • Chi Wai Shum

            And in the video, it did not really work reliably.

        • JSmath

          iks, his point is that a squib cycling the action while firing automatic DOES NOT CHANGE ANYTHING. Because if you get a squib to cycle while firing auto, you will still definitely stack your bullets in your barrel before you realize what’s wrong.

          It’s hilarious that people are suggesting that they are going to hear a squib pop off during full auto fire and respond fast enough to change anything versus with how this pull&release trigger works.

          • iksnilol

            I get the point, it was just poorly argumented with the whole “if it’s a squib it will just stop like any other”.

            Squibs screw people over no matter the action type. I think the people worried about it are worried about the “indirect” nature of the second trigger pull.

          • JSmath

            Right, and I at least got the impression you and I are at least aware that the indirect nature of the second fire is not beyond control. In fact, considering releasing the trigger isn’t a forced but deliberate action, those fears are essentially like comparing semi-automatic fire to being completely out of control fire because you don’t have to cycle a bolt or hammer/slide to fire the next shot.

            Some sort of disconnect would be nice. I actually posted on Military Arms Channel’s video comments asking about two methods I’ve considered feasible to non-fire during the release stage; going to require someone with a working unit to verify.

          • JSmath

            Just a followup btw, but if you hold the trigger in, switching back to Semi will disengage the fire on release function.

            So, this design is actually safe as hell. Especially versus others like the mini-14 staple mod, which can’t be disengaged.

          • Sianmink

            If you get a squib that cycles the action, and you’re shooting rapid whether full auto or semi, you’re pretty much screwed either way.
            Thankfully, cycling squibs are super rare.

      • RickOAA .

        If you can control the pull, you can control the release. Nothing to it.

    • Bill


  • SP mclaughlin

    DIY AN-94 here we go.

  • nova3930

    Instant double tap ability

  • AndyT

    Would be great for a boat gun

  • Nicholas Chen

    I would like to try this in a 9mm AR and run it for fun in a USPSA action match.

    • dhdoyle

      Can’t see the application here. If you finish your course of fire with the trigger pulled, your score will be hurt by the next shot. It will either add time to the clock, or dock you in a Virginia count stage. Then there’s the whole “Unload and show clear” thing.

      Besides, If I were an RO, I’d DQ anybody whose firearm “doubled” on one trigger pull. I wouldn’t buy the argument that “It’s a feature, not a bug…”

      • totenglocke

        “Besides, If I were an RO, I’d DQ anybody whose firearm “doubled” on one trigger pull. I wouldn’t buy the argument that “It’s a feature, not a bug…””

        Thus affirming yet again that RO’s are dicks who’s primary intention is to ensure that paying customers are having the most unenjoyable experience possible.

        • NDS

          Operative phrase was “If I was an RO”

          An actual RO, such as myself, especially one in a match setting, actually understands technology and can have a rational conversation with another human being. Usually.

      • Nicholas Chen

        Most stages require two shots per paper target. I can pull the trigger on my STI Steel master pretty quickly but accuracy suffers. You just need to plan out when and where to use this. Don’t forget you don’t have to use the binary system and just revert back to semi auto.

      • Phaideaux

        You can cancel the second shot by moving the selector back to semi before releasing the trigger.

  • J-

    I’ll take that with a side of chili fries.

  • Joshua

    Dissapointing, as I would hope Franklin could figure out a way to use an M16 carrier to trip a sear allowing the shooter to release the shot only after the bolt goes into battery.

    That would be auto sear that is in the burst and auto FCG of the M16/M4/M4A1.

    • Jack

      Only if the carrier itself released the shot. If they could engineer it so the trigger pull or release firing was simply canceled if the bolt wasn’t in battery then that shouldn’t be a problem. Alternatively (and probably more problematically) if you could design the trigger to “lock” in place until the bolt was in battery, that may also fly.

      • RickOAA .

        Incorrect. PSL’s have been recalled for having safety sears in auto sear locations, and even AK receivers with welded over sear holes have been recalled as the ATF considers anything that has had a full auto sear hole to still be a machinegun even if welded over.

        • Jack

          I don’t understand your analogy.

          • RickOAA .

            My point is that a legal sear trip is probably not happening, even if it merely acts as a timing device.

    • NDS

      Yup my thoughts too, even if it didn’t release the hammer as in the M16 family, it would still be a second sear and likely illegal.

  • Marcus Toroian

    I’ve had this option on every AK I’ve owned in the past 6 years. I’m on prototype 5. Trying to figure out a way to make it switch on and off. It’s stupid easy to do with these trigger groups.

    • Ken

      Look at an M16 burst fire trigger group design. There are two disconnectors, one with a selector tail and one without. The AK disconnector is fat enough that you should be able to easily squeeze two disconnectors into there side by side.

  • Phaideaux

    The franklin trigger is $400 and drop in, any idea on how expensive the echo will be? And if it will be a drop in?

    • thedonn007

      I was going to ask the same question. I nee one of these triggers in my life.

    • NDS

      When I read about this on their site it said lowers may require machining for fitment; owner of the shop ordered one so we’ll see what it entails.

      • aka_mythos

        I saw the same thing and was reading everything I could. It seems like they anticipate trigger packs housing to be snug or too snug depending on the fire control group pocket of the lower reciever. That they say machining the reciever might be necessary because they don’t want excessive force applied to their trigger’s housing.

  • ant1248

    I wonder if they could make it so it would only release if it was in battery (probably not auto release after in battery I could see that being full auto designated).

  • Hensley Beuron Garlington

    Dangit! I replaced the Tapco G2 trigger in my old AK I modified a bit too much in an attempt to smooth out the action. I could of kept it! NOT! It became a “binary” trigger system as well. It wasn’t safe at all, but it was a good learning experience. AKs make for good experimentation like that.

    How does one keep it from firing if I pull the trigger and don’t want to release that second shot? The sear idea mentioned above is also very important! I haven’t watched the video yet, but I will as soon as I can. I hope that is addressed.

    Similar systems are found in skeet shooting, paintball, and airsoft. Though, wasting a paintball or bb in a safe direction isn’t as much of a concern as having to discharge a bullet to put the gun in a safe mode for storage.

    • Phaideaux

      If you put the franklin one back on semi while the trigger is back it will not fire the second shot when released.

      • Hensley Beuron Garlington

        Hey, thanks for the information. That is pretty cool.

      • Hensley Beuron Garlington

        I think a selector switch able to toggle between traditional mono semiautomatic and this new, stereo semiautomatic is needed!

        Again, this is why the NFA is bullshit and the Second needs to be interpreted as is!

        • Hensley Beuron Garlington

          I see that it already let’s us select! My bad. LOL. I’m late to everything.

    • Cymond

      This isn’t for slow fire, it’s for ripping off rapid double taps. Ib dint see it as any more dangerous than sound taking in the usual manner.

      • Hensley Beuron Garlington

        I don’t find it dangerous either now that I know I can toggle it at least.

    • iksnilol

      Hmm. What about holding the trigger while removing the magazine and working the action? It should be easy on an AR.

  • Harrison Jones

    Someone at the ATF loves us! But they have an evil twin :'(

  • Cal.Bar

    Fortunately, the state of CA, keeps us safe from such things as they are illegal here.

    • RickOAA .

      Fortunately, the state of California is on the other coast…

  • tincankilla

    why is it that gun people love adding extra syllables? “bianary” is the new “ambidextrious”

  • Bill

    The biggest issue I see is that it is difficult enough to train in a good trigger press and reset – this is going to make that all weird. Plus, if you’ve trained in a good trigger press and reset, why bother with this?

  • Kyle

    I am flat out amazed that the ATF let this through. Cute semantics arguments aside you are essentially getting a rifle with a two round burst.

    • hydepark


    • JSmath

      The ATF has made strict but sound judgments on these matters before and that’s exactly why so many people are completely confident this is here to stay.

  • Cymond

    Sorry, I can’t watch the video on my mobile device right now, it locks up whenever I try.

    However, double triggers have been around for a long time. The law says one shot per “function” of the trigger, not per pull. Pulling and releasing are two separate functions.

    Checkmate guns offers an AR-15 with a doube-shot trigger called the Liberator. TFB reported on it back in August 2014.×39/ Unfortunately, they don’t sell the trigger separately, only complete guns for $2400!

    Also, as others have said, a Mini-14 can be modified to fire like this by inserting a thick staple into the fire control group.

    Finally, many seem to think this is dangerous. I don’t see it as any more dangerous than firing rapid double taps, or shooting a gun with a 3-round burst. You just need to plan and intended to ALWAYS fire a double tap. Don’t try to fire slow, single shots.
    Again, I can’t watch the video, and haven’t looked into the Franklin or Fostech versions yet. However, I hope someone makes a version that is selectable between singles and doubles. The Checkmate is only capable of doubles.
    And, since Fostech is making one, I wonder how one would perform in a bumpfire stock.


    And this one from an unknown person or company. His description on the video indicates that it is selectable between doubles and singles:

    • Bill Akins

      You wrote….”The law says one shot per “function” of the trigger, not per pull.”

      Almost correct. The NFA law actually says “….per SINGLE function of the trigger.”

      But that didn’t stop ATF from banning my original spring loaded Akins Accelerator bumpfire stock which also only fired one shot per single function of the trigger, so the spring was irrelevant to the “single function of the trigger” law but the courts let them get away with their injustice. But it was a hollow victory for ATF since my Accelerator stocks work fine without the spring by using isometric tension and are currently sold by myself and Fostech Outdoors.

      • Cymond

        Yeah, I remember your Accelerator. That thing was genius in its day. I found out about it approximately a month before ATF came down on it. At the time, I was outraged that they ignored the plain language of the law. Now I practically expect it.

      • Ned Beatty

        I’d buy one of the AA if it was in the price range of the other bump fire stocks.

        Why not sell a version without the trigger pack? It would have to be cheaper.

      • RickOAA .

        Still at it, aye!?

    • Cymond

      So it turns out that they posted this video a year ago: How did this not make news until now? They posted more videos back in September, several of which have less than 1000 views!

      Also, they have a selectable release trigger, I guess for precision shooting.

      • Wingbert

        They should’ve paid off somebody who’s youtube famous to do a video earlier.

  • smartacus

    me want that trigger in my PMR 30 and Ruger Mk2!!

    • smartacus

      or in a double-barrel 1911

  • smartacus

    and i’d like to see it up against Jerry Miculek’s ATF-legal right index finger

  • Twilight sparkle

    I bet some of the guys at arfcom that we’re building “bump saws” could get it to run reliably.

  • JoshCalle

    This happened to me on my WASR 10/63. I eventually figured out that I had woven the shepard’s crook around a couple of pins the wrong way. It was cool but it had a tendency to walk one of the pins out.

  • Anonymoose

    Combine it with a Defendar stock and get it to run without the hammer following the bolt home, and we’d really be in business.

  • myndbender

    If I could justify the $399 price of admission, I’d buy 1 or 10 just because it would drive the anti’s crazy & before ATF reverses yet another ruling. And at $399, it’s close to the same price pt as the new gen slide fire stock. I think it will also make bumpfire stocks even more pointless b/c of ease of aimed fire plus the cool factor of having a functioning 3rd selector setting. Hope Fostech is either less expensive or can improve rate of FTFs though…

  • JoelM

    What I want to know is how long it will be till some statist figures out how to ruin this by writing the atf for clarification on something related to it.

  • Will

    This is NOT new technology.
    In 1970 I shot trap with a man who used a release trigger on his trap gun. He had severe arthritis in his hands and it was not as painful for him.
    Everything old is new again.

  • Sianmink

    “Dissapointing, as I would hope Franklin could figure out a way to use an M16 carrier to trip a sear allowing the shooter to release the shot only after the bolt goes into battery.”

    Indeed. shot ‘queueing’ wouldn’t technically be illegal, and would be sweet as you’d get a 2-shot burst at full cyclic rate.
    Someone, get on that.

  • Wingbert

    Interesting novelty. I wouldn’t want to have to think about how fast i’m pulling the trigger in a defensive situation.

  • dltaylor51

    With all of the stops to clear the gun this thing would be a great way to get yourself killed in a real firefight.

  • Nate H

    I need one of these for my race gun. Mwahahaha unfair competitive advantage, or just gaming the rules? I’d sure argue my case for the latter lol.

  • Eric Eskau

    You don’t have to eject the round, just pull the bolt back till you hear the click of the hammer reset and then let the bolt close, this happens on my bump fire stock sometimes and that is all I do.

  • The Brigadier

    Tac-Con also makes a trigger based bump fire system. It comes with a new trigger assembly and a selector switch. Prices are for a right hand model and a more expensive one for an ambidextrous one. It too is completely legal and they have the ATF letter on their website for all those skeptical that they sell a full auto choice for their AR. Its a lot slower than the one on the original M16-A1 model, but you can still rock and roll at a slower beat. Go to their website and check out the fun where they empty 30 round mags with so much glee.

  • RickOAA .

    If someone comes up with a trigger assembly at half the price that doesn’t require fitting…maybe.

    I always had fun with the 3 round burst on the M16. A two round “binary” mode may actually make more sense.

    At any rate you’ve gotta love the ingenuity displayed by our industry. Slowly but surely, all the arbitrary laws on the books are being completely invalidated.