Review: Michiguns MOACKS Plain Gas Key Staking Tool

Ever had a gas key that came loose? I know I have, especially with some of the bargain prices bolt carrier groups that I have bought over the years. The Michiguns MOACKS Plain is designed to allow the home gunsmith the ability to stake the gas key screws properly without expensive machines. This particular BCG is an IWI that I purchased on closeout and hasn’t come loose yet, but it is a matter of time in my opinion.

There are many people that believe that thread locker alone is sufficient but I have had at least two gas keys come loose with only thread locking compound keeping the screws in place. When I attended the Semper Paratus AR-15 armorer’s course we fixed a couple gas keys with the MOACKS Plain, after that I knew I needed to add one to my gun tool box.

You can see the weak staking on the BCG below, we will also replace the screws with the proper grade screws at the same time.

Gas Key

The MOACKS Plain is made from pre-hardened 4130 steel and uses quality screws to accomplish the staking operation. The tool itself is very nicely machined and the included 1/8″, 9/64″, and 5/32″ Allen wrenches are also high-quality US manufactured tools.

MOACKS Plain Profile

The two holes at the top of the tool are so that you are able to index the tool to the proper location. The idea is to stick the long side of the proper Allen key into the hole and make sure it goes into the gas key screw. Your gas key screw could be 1/8″ if the screws are Mil-Spec or 9/64″ if they are the standard commercial grade units.

MOACKS Plain Top

Two hardened screws on either side of the tool will be tightened in order to stake the gas key properly, the white substance is lube to keep the screws moving smoothly when deforming the gas key.

MOACKS Plain Screws MOACKS Plain Inside

Removing the commercial grade screws you see that they used thread locker as a backup to the less than ideal staking job. The screws came loose rather easily with just a screwdriver, I didn’t use much torque at all.

Gas Key Removed

In order to make sure the gas key is nice and tight against the bolt carrier body I will need to remove the old thread locker and clean off anything else that might be in the way of the two surfaces mating.

Bolt Carrier Group With Gas Key Removed

Reinstall the gas key after applying sealant and use new grade 8 screws. They should have a squared head like you see below and fit flush.

Gas Key Installed

Now locate the tool in the proper place with the two holes on top with the proper size Allen wrench and hand tighten the screws on the side.

Locating MOACKS Plain on Gas Key

From this point, it is as simple as tightening the screws till they bottom out on the tool. This will provide a secure and uniform stake on each side of the screws.

Using MOACKS Plain

You can see the rounded tips of the screws deforming the gas key just enough to provide a secure stake.

MOACKS Plain Staking

The finished product is clearly secure, these screws aren’t going anywhere anytime soon. Just a quick touch up with a bit of cold blue and the job will be done.

Staked Gas Key


Is the Michiguns MOACKS Plain worth the $85 MSRP? Yes, especially if you are a heavy AR shooter like I am. The ability to replace parts like the gas key and bring them back up to snuff or even repair sub-par jobs like was done to this BCG originally is invaluable.

You can learn more about the MOACKS plain on the Michiguns website HERE.

Patrick R

Patrick is a Senior Writer for The Firearm Blog and TFBTV Host. He likes guns and has liked shooting guns for as long as he can remember. You can follow Patrick on Instagram @tfbpatrick, Facebook, or contact him by email at

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


  • derpmaster

    A cold chisel and a hammer does the same thing for about $5 total investment.

    • Jason Lewis

      Ya beat me to it.

    • A chisel and a hammer also do roughly the same thing as a .357 wadcutter, the difference is that one is the right tool for the job. If you somehow manage to get a highly-fool-resistant tool like this to screw up, you’ll maybe have a gas key that’s staked at a goofy looking angle or something; screw it up with a hammer and chisel/screwdriver, and you have a ruined gas key and gouged-up bolt carrier.

      • Ron

        I bought one years ago based on the recommendations of Pat Rogers following attending one of his classes and a few of guns (all mil issue) not have well stakes keys. It certainly stakes the hell out of a carrier key bolts. To say they are not easily removable is an under statement

  • Wolfgar

    The MOACK tools have been top notch. I got a reply from Chris Bartocci about which mill spec gasket sealer for the gas key that Colt used. He said it was from Loctite. I have used

    Permatex Aviation Form A Gasket with perfect results.

  • Gary Kirk

    As long as you don’t exceed 0.025 upward protrusion, and maintain a parallel surface of the gas key.. Who cares.. Field service of a key come loose is to re-tighten the screws and re-stake the key @ 120° (3 evenly placed) around each screw head. Until a new key and screws can be installed and staked/sealed properly if possible. Or replace the bolt carrier with a new unit.

    • Joseph Goins

      Or just save yourself the hassle and buy a new carrier. I’ve seen too many home armorers screw up and have gas leak out of it. Imagine if that happened when you actually needed it.

      • Wolfgar

        You can purchase a new bolt carrier if you like but using a MOACKS staking tool and the proper sealer is the proper way of fixing a loose gas key or replacing a worn key if you want it to last.

        • Joseph Goins

          What I described about the home armorer’s failing is with the proper sealant and staking tools.

          • Wolfgar

            So what you are saying is if you use the proper stacking tool, torque spec, new grade 8 screws and sealant it will fail? OK!

          • Joseph Goins

            Human error, mate. It’s a poor workman who blames his tools.

          • Wolfgar

            The human error is using the wrong tool!

          • Joseph Goins

            No. Human error has nothing to do with the tools. It has to do with knowledge, experience, luck, etc. One could properly stake the key with just a hammer and staking tool. The tools are unimportant.

          • Wolfgar

            So using a tool made for the job is illogical to you when all you need is a chisel and hammer. Got it! I’ll try to inform BCM, Colt, FN, Daniel Defense,etc they have been staking their bolt carrier keys all wrong.

          • Joseph Goins

            Are you sure you aren’t a liberal? You definitely have the intelligence of one.
            I never said that this tool is bad or shouldn’t be used. I only said that “I’ve seen too many home armorers screw up and have gas leak out of it.” I’m not saying you or anyone else can’t properly stake the gas key. I merely pointed out that I have seen people fuçk it up quite often. Quit being a diçk and freaking out.

          • Ron

            The MOACK tools (both full size and mini) take experience and luck out of it and make it next to impossible to screw up.

          • Wolfgar

            Hey Joseph, you first recommended purchasing new bolt carriers instead of repairing loose carrier keys because you have seen too many home repairs fail. All I stated was using a MOACKS with proper sealant was the proper way to fix or replace the gas key if one wishes to fix it properly without purchasing a new carrier. You then implied the bolt carriers repaired with proper tools, meaning “MOACKS I assume” and sealant were the carriers you have seen fail?????, Then you mumbled something about human error and a poor workman who uses tools as excuses for failure???? I replied again and stated using the wrong tool is the human error. Then you said you didn’t need proper staking tool like the MOACKS since it is knowledge, experience, and luck with a hammer and staking tool which is all that is needed to repair a carrier key and the tools used are not important ?????? Before you call me a liberal and use profanity’s, I would highly recommend you check your med intake, something is seriously messed up with your behavior and thought pattern.

  • Joseph Goins

    I don’t get the fascination with building the most important part of an AR.
    Makes no sense.

    • roguetechie

      For some of us it’s not fascination so much as just something we genuinely enjoy…

      For me the sounds of whirring machine tools, the patience and deliberation enforcing act of measuring twice to cut once, and the sheer joy of turning hunks of dead metal and etc into useful “things” all remind me of summers spent with a grandfather I will never stop missing…

      It’s a connection to something real and tangible in a world where that is increasingly precious.

      Plus, frankly I’m one of those guys whose dreams and wish list often outstrip my financial means to acquire them!

      In, other words it’s complicated…


    Y’know… I have no clue how the holes in the golt carrier that you can see when the ejection port is open interact with the gas key at all, or if they do anything, period.

    Anyone have an “x-ray” / cutaway diagram?

    Mondays and Tanqueray don’t go well together.

    • Paladin

      The holes in the dust cover dimple vent gasses once the bolt is unlocked, the one to the rear is for the firing pin retaining pin.

  • Wolfgar

    This is mill spec if using the proper staking tool and gasket sealer.

    • Scott Wagner

      My point is that this isn’t the milspec staking tool, and thus, in Pat’s own words, only for idiots.

      • Wolfgar

        The MOSAKS tool gives mil spec staking. So what is the mil spec staking tool?

        • Wolfgar


  • Moonman45


    No torque wrench on the allen key? over torquing that could lead to carpal tunnel!
    No safety glasses or non-latex gloves?
    where the hell are the eyewash stations?

    Where is the disclaimer/safety prologue telling us to check the chamber before during and after completing the mentioned task?

    Absolutely ridiculous, expect my invoice for “critical advice pertaining and non pertaining the superfluous maintenance tasks gun owners with too much time on their hands fuss over”