Gemtech GMT-300 Supersonic Suppressor

The new Gemtech G-Core series GMT-300 suppressor for .300 BLK.

The new Gemtech G-Core series GMT-300 suppressor for .300 BLK.

Gemtech (Gemini Technologies) out of Eagle, Idaho has released the new G-Core line of suppressors at SHOT Show this year.  Gemtech started as a consortium of suppressor designers back in 1993, and has been creating and expanding suppressor technology ever since.  In fact, Gemtech has documented several of their 5.56mm suppressors from another line with over 100,000 rounds fired through them without a loss of dB reduction.

Gemtech is a leader in suppressor innovation.

Gemtech is a leader in suppressor innovation.

Talking to Casey Foster at the Gemtech booth I learned that the success of the G-Core line is a direct result of Gemtech recently going through a major overhaul of their manufacturing process.  That overhaul included adding a significant amount of automated technology, including more advanced CNC machines, to increase productivity and save costs.  At the same time one of the Gemtech engineers began to develop a new concept for suppressors that resulted in the development of the patented G-Core suppressor line.

The business end of the GMT-300 with Gemtech machined logo.

The business end of the GMT-300 with Gemtech machined logo.

A view of the patented GMT-300 baffle system.

A view of the patented GMT-300 baffle system.

G-Core suppressors were designed not only for sound suppression, but with accuracy in mind as well.  Designed using the latest Computational Fluid Dynamics (CFD) software, the G-Core suppressors went through Finite Element Analysis (FEA) to make sure the suppressors would end up both durable and light weight.  Finally, each model went through rigorous live-fire testing to ensure all requirements were met.

The face of the GMT-300.

The face of the GMT-300.

The attachment threads of the GMT-300.

The attachment threads of the GMT-300.

The end result was that the G-Core line of suppressors are the strongest Gemtech suppressors ever made, and the strongest on the market, according to Gemtech.  Foster claimed that in recent testing using SOCOM and M4 tables, the G-Core suppressors far exceeded any competitor’s suppressor despite being torture tested well beyond the level at which the competitor’s suppressors had failed.  The G-Core suppressors withstood the testing to a “level 13″ without reaching a failure point.

Another look at the patented GMT-300 baffle.

Another look at the patented GMT-300 baffle.

The most impressive of the G-Core line is the GMT-300 Blackout suppressor.  Designed for the .300 Blackout cartridge, the GMT-300 accomplishes what Foster says no other suppressor has succeeded in doing – suppressing “supersonic” ammunition to hearing safe sound levels.

GMT-300 side by side

For the longest time one of the drawbacks to the effective use of suppressors was the limitation on using subsonic ammunition.  Though a suppressor could be used on supersonic ammunition, the resulting noise reduction would not quite reach the hearing safe levels.  Now it appears Gemtech has found a way to bridge the gap and allow shooters to suppress supersonic ammunition – well, at least in .300 BLK.

The side view of the GMT-300 suppressor.  Note that all the components are made of titanium.

The side view of the GMT-300 suppressor. Note that all the components are made of titanium.

GMT-300 Blackout Suppressor (.300 BLK only – subsonic AND supersonic)

  • Length – 6.7 inches
  • Diameter – 1.5 inches
  • Weight – 14 ounces
  • Material – Titanium
  • Tube Finish – Desert tan Cerakote with reduced visual IR signature
  • Core Finish – Titanium
  • Mount – 5/8 – 24 Thread
  • Sound Reduction – 36-39 dB
  • Sound tested on a NEMO 16” with PNW 147gr supersonic and 187gr Gemtech subsonic ammuntion
  • Special dB Test Note – Hearing safe on a NEMO 7.5” barrel with PNW 147gr supersonic and 187gr Gemtech subsonic ammunition.
  • MSRP – $995
An angled look at the business end of the GMT-300 with machined Gemtech logo.

An angled look at the business end of the GMT-300 with machined Gemtech logo.

The tested GMT-300 suppressor fired 1100 rounds without cleaning, and continued to perform as designed.  The Gemtech GMT-300 Blackout appears to be an incredible advancement in suppressor technology.  It should be very interesting to see what kind of results they can achieve with their .223 Rem. and .308 Win. suppressors, which they hope to have ready for market later this year.  Foster explained that current testing of the high pressure .223 and .308 rounds has caused pitting near the suppressor entrance where the pressure is highest, so more work is in order before release.  If Gemtech can accomplish supersonic hearing safe noise reduction in those extremely popular calibers, it could revolutionize the market.

 

 

 

 





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  • MrSatyre

    The insides make me wonder what sort of muzzle flash you’d get if your fired this thing on without the outer casing? Totally stupid, I know, but I gotta wonder!

  • bbmg

    Now
    it appears Gemtech has found a way to bridge the gap and allow shooters
    to suppress supersonic ammunition – See more at:
    http://www.thefirearmblog.com/blog/2014/01/16/gemtech-gmt-300-supersonic-suppressor/#sthash.XVNlaOzU.dpuf
    Now
    it appears Gemtech has found a way to bridge the gap and allow shooters
    to suppress supersonic ammunition – See more at:
    http://www.thefirearmblog.com/blog/2014/01/16/gemtech-gmt-300-supersonic-suppressor/#sthash.XVNlaOzU.dpuf
    Now
    it appears Gemtech has found a way to bridge the gap and allow shooters
    to suppress supersonic ammunition – See more at:
    http://www.thefirearmblog.com/blog/2014/01/16/gemtech-gmt-300-supersonic-suppressor/#sthash.XVNlaOzU.dpuf
    Have the people at Gemtech broken physics? Maybe there’s a misunderstanding here but there’s no way you can stop supersonic ammunition from making a “sonic crack”, and there is nothing that would particularly distinguish the monocore baffle stack they are using from similar designs on the market.

    • bbmg

      Darn discus and copy-paste…

      • gunslinger

        you could edit the post.

        • bbmg

          Not when you post as a guest

          • http://www.thefirearmblog.com/ Phil W “Senior Writer TFB”

            Well hell don’t post as a guest:-)

  • TheSmellofNapalm

    Is it a safe hearing level even on an SBR?

    • Dan

      It’s not safe even on rifle length. No supersonic ammo will be.

      • TheSmellofNapalm

        Cynical much?

        • Dan

          go ahead and shoot supers without hearing protection if you want. hell, go 300 yards downrange and listen to supers fly over your head without hearing protection. your ears not mine.

  • Dan

    unless they’ve figured a way to suppress the supersonic crack of the projectile after it’s left the barrel, there’s no way this is hearing safe.

    • Anton Gray Basson

      Hate to disagree there, been using a custom suppressor and super sonic ammo for hunting and the bullet crack isnt all that loud from your perspective as the shooter . the main reason for the use of subsonic ammo is the lower gas volume and pressure and the fact that the crack can alert a target at range. the only reason for my pairing of suppressor and regular ammo is for better penetration and bullet performance.

      • Micki

        Worth bearing in mind though, that just because a sound pressure level sounds low, it’s not necessarily hearing-safe. I’d still wear hearing protection, just in case.

        • Dan

          Target pullers many hundreds of yards downrange wear hearing protection, because supersonic cracks are NOT hearing safe, period!

      • MZupcak

        The only targets that can be “alerted” by the crack are not alerted if you do your job right (i.e. hit said target). The bullet arrives before the sound wave.

        • Anton Gray Basson

          meant to type secondary target. Also a bullet doesnt always arrive faster than sound through its entire flight.

          • gunslinger

            but if this is for supersonic ammo, then by definition, shouldn’t the bullet arrive before the sound wave?

            where is the break point in which the sound wave would catch up to a bullet, if it was able to fly straight, but air drag would act normally to reduce the speed?

            i think the distances over which shots are fired, it wouldn’t be a problem but still

          • Anton Gray Basson

            My understanding is that the crack is a one off event it would be generated by the tip of the air displacement cone touching the ground. Also despite it having a intial rating of between 110 and 160 dB the air volume displaced isnt that great which means that, and I have observed, two people close to each other with a round passing near by may not notice the same thing. One may hear a round popping as it comes by and the other may not even notice it but hear the report of the weapon that fired the round.

          • MZupcak

            Good point.

        • Guest

          Target pullers in pits hundreds of yards downrange wear hearing protection. Because supersonic cracks are NOT hearing safe! Period!

      • Dan

        Incorrect.

        The supersonic crack alone is around 140db. That is not hearing safe.

        If it were, why do target pullers in the pits wear hearing protection? They are many hundreds of yards downrange.

        They wear hearing protection because supersonic cracks are NOT HEARING SAFE!

        Just because it “doesn’t hurt” doesn’t mean that permanent damage isn’t being done. Pain is a terrible threshold to use to determine hearing damage. Supersonic cracks are particularly insidious as they are
        impulse noise and can do more damage to the unwary.

        The main reason for the use of subsonic ammo is it’s the ONLY way to be hearing safe!

        Hearing damage is incremental and PERMANENT.

        There’s a saying with hearing damage — “you don’t hear a thing, until you don’t hear a thing”.

        • Danmaku

          The second part to the saying is: “WHAT DID YOU SAY?!”

  • WFA

    There are so many variables that effect suppressor performance, least of which is the human ear.
    In my experience the use of CFD and FEA has some relevance to design but much more is learned with rigorous scientific testing.

    All we ask of the articles here at TFB is that they professionally written, that is that everything that is said or written
    must be capable of being substantiated.

    This article makes so many bold statements without any evidence or test results that it risks sounding more like Gemtech marketing.

    If you can arrange an independent test (Andrew Tuohy/Vuurwapen style) then I will happly believe what I am reading.

    • Dan

      This article makes statements which are actually dangerously untrue, like the claim to make supersonic ammo hearing safe.

      This article is simply parroting press release and marketing material. There is little to no content here.

      • http://www.thefirearmblog.com/ Phil W “Senior Writer TFB”

        Well sir when it’s a new product and you have tested it about the only thing left is to use the information you’re given.
        Maybe it’s safe with supersonic ammo. The people at Gemtech think so.

  • grendal1989

    Would this hold true of 7.62×39 ammunition? I know they are very similar ballisticly.

    Also, I wonder if it is still rated for .223, albeit without as good sound reduction.

  • Aaron E

    Hey everyone, thanks for the comments. I figured this article would generate a lot of discussion. I apologize if the article sounded like a Gemtech advertisement, I really did not intend it that way. I meant it to be a reporting of what I was shown. I was, however, very excited about the potential of supersonic suppressors at “hearing safe” levels. Though familiar with suppressor basics, I do not claim to be an expert on the topic whatsoever.

    I have talked with the Gemtech guys three separate times to make sure I wasn’t misinterpreting what I was told, or what was written in their literature. Each time the claims were restated, and by different representatives. I’m not sure what they consider “hearing safe”, other than I was told the GMT-300 could be fired without hearing protection. Whether that is from the shooter’s perspective, or overall, was not clarified. I tried to word the article to clarify that the information was based on Gemtech claims, not my own, and even wrote statements with questioning tones.

    I was not present during the testing to verify the ability to fire hundreds or in some cases thousands of rounds through their suppressors, but was assured each time about the durability of the Gemtech suppressors as stated.

    I reported what I was told and what was in their literature. Either Gemtech is a big, fat liar … or they really have an amazing product.

    • Dan

      I doubt the gemtech people would be willing to stand next to me while I go through a couple 30rd magazines. supersonic crack itself is about 140db, that’s well after the projectile has left the muzzle.

      there’s a reason why target pullers hundreds of yards downrange wear hearing protection.

  • Aaron E

    One last clarification from the Gemtech reps. Firing a 7.5″ barreled SBR, using PNW Arms 147gr. .300 BLK ammunition, produced around 137-139 dB. That is just under the U.S. OSHA limitation on “impulse noise” that limits workers exposure to not exceed 140dB.

    The measurement was at (1) meter to the sides and rear of the muzzle, so I would still be leery of shooting an SBR with GMT-300 without hearing protection.

    However, with longer barrels, the dB level at (1) meter to the sides and rear began to drop significantly. The Gemtech reps advised that dB levels dropped to the mid 120’s on the longer barrels.

    Still not as soft as muffs or plugs, but all things considering a level that could be considered “hearing safe”, especially for the benefit of shooting supersonic.

    • Dan

      the bare supersonic projectile itself, hundreds of yards downrange, will be near 140db. how would a longer barrel reduce that to 120?

      • Aaron E

        I’m sure that’s the million dollar question that many other suppressor makers are wanting to ask Gemtech, but again, it is what they are claiming in person, and in literature – as reported. I am not defending their claim, only that they did in fact claim the results. Any research on the matter, I’m sure it would benefit the readers.
        Not being a physicist I couldn’t begin to try to explain all the dynamics of the engineering work Gemtech has done, but I sure am excited to see if it all plays out – especially if they can work out the .308 and .223 suppressors.
        As far as dB differences all I know is that there is definitely a difference in noise levels at the shooter’s position on a 10.5″ Rock River I shoot (5.56mm) than the noise level standing next to the rifle when fired. And the noise levels from the 10.5″ rifles we use, are again much different from our 14.5″ and 16″ barreled rifles.

        I imagine that may play a role in how a longer barrel could effect dB levels at the shooter’s position, but again, I’m not a physicist.