Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Harald Hansen

    Very pricey, but seems to be useful when your life is dependent on having functioning magazines. I’d like one for my Mini-14, which is a bit finicky when it comes to magazines.

  • Crabula

    That is a pretty steep price, but I am pretty sure that it has to do with the tolerancing of the part. They probably have to machine it to very high tolerances. If your gauge is out of spec, there is no way to know whether or not your magazine is out of spec as well. Thats the only thing I can think of.

    Arent the dust covers on p-mags supposed to double as go/no-go gauges for the feed lips? I thought I read that somewhere.

  • gunslinger

    60 bucks seems steep for a piece of metal, but depending on the mil-spec tolerances, one would need time and money to make the guide correctly. i mean what’s the point of a calibration tool that isn’t to spec?

  • Matt

    That price is outrageous. As a person with knowledge of machining practices I can tell that “close tolerances” on something like that are very easy to achieve. We use machines nowadays that work within one tenthousandth of an inch as standard. On a shape like that gauge it is no problem.

    It’s sad they are trying to profit that much off of a product which is mainly designed to save lives. I say that cause civilians don’t really NEED it. I can easily take a caliper to my magazines and check the spread. Or hell just go to the range and shoot them. If they work. Great.

    But a soldier doesn’t have the time or tools to do that sometimes. So they might need this.

    I could understand that price only if they were actual military product that bravo got ahold of and are selling. As they would be a little rare.

    But for something they manufactured, for that price it should light up and buzz or something. A simple shape of metal is very easy to make.

  • jdun1911

    It’s pricey but it will extend your magazine life by knowing if it defective or not. With that said, if my life depend on it I will throw away any magazines that I have doubts. My life is worth more than a few bucks.

  • If anyone has one of these it would be interesting to get the dimensions of the gauge Shouldn’t be too had to make one as machining to sub-thousandths tolerance is no big deal.

    John. (aka Fr. Frog)

  • jdun1911


    “But a soldier doesn’t have the time or tools to do that sometimes. So they might need this.”

    Honestly they don’t need this.

    This is what I tell anyone if they doubt the reliability of the magazine when their life depend on it.
    1. Put the magazine on the ground.
    2. Collapsed your butt stock.
    3. Than fucking whack the magazine to death with the butt stock so you won’t be tempted.

    Your life is worth more than a $10 magazine. Just remember that.

  • Hu. Seems like someoneelse needs to start making them.

    And, uh, these won’t extend thelife of a magazine, these are specifically shortening the life of bad magazines by poving they are defecive sooner

  • That’s the idea-get rid of bad mags before they “get rid of you.” The only reason to keep defective mags around is to use them for training on malfunctions. Those mags need to be distinctively marked. (I spray some red paint on them.)

  • Buster Charlie

    I have in front of me a scan of a print for the STANAG magazine manufactured by Imbel.

    The distance between magazine lips is 11.6mm +/-0.05mm

    For those of you in America (me) That would be literally +/- 0.00197
    But I imagine the closest English print would say +/- 0.002 since you wouldn’t give a tolerance to the ten-thou if it was in the thousandths.

    So what am I saying here?

    Even a simple +/- of 0.001 could be achieved on such a simple shape all day long on a worn manual Bridgeport without too many rejects and you’d be able to make gauge blocks with half the tolerance of the actual part, and if you had a really good manual machine, or a CNC machine easily, you could turn out parts with tolerances of +/-0.0001 and have something that beats the 10:1 rule.

    But then again, people are allowed to charge whatever they think they can convince people to pay.

  • Buster:

    I am building a database of AR/M16 stuff. Is there a chance you could send me a copy of the mag drawing?

    Hopefully they won’t block my email address = frfrog [at] commspeed [dot] net


    John S.

  • Matt

    I agree jdun. If it’s questionable, chuck it. Or do like I do and buy pmags and not worry! 😉

  • Ken

    Being a machinist of 16 plus years I think the price is nuts. Just my 2 cents.

  • Sean

    Hopefully if these guages are produced by a more affordable source with dependable tolerances someone will post an update with a link. I have some new Fusil magazines I want to check, I purchased them in quantity and they don’t feed well in my AR.