Subsonic Ammunition That Won’t Cycle the Action: Good or Bad?

    About a week ago, JMac Customs has published a video where they were shooting a suppressed AK chambered in 5.45x39mm. The standard supersonic ammunition performed as expected, decreasing the sound to a hearing safe level. However, they were also shooting Detroit Ammo Co. subsonic 5.45x39mm ammunition which wasn’t powerful enough to cycle the action rendering the gun to a manual repeater. My first reaction was that this ammunition is worthless for a semi-auto gun. However, later I thought about a situation where this kind of ammunition can actually be useful. Let’s watch the mentioned video first.

    Imagine a situation (hunting, combat or whatnot) where you are running a suppressed gas operated firearm (not necessarily an AK and 5.45x39mm) and for whatever reason you find yourself in an unexpected situation where have to make one or several shots that have to be as quiet as possible not to compromise your presence or location. Ideally, you will have a dedicated gun for such a shot like an integrally suppressed .300 Blackout bolt action rifle sending subsonic 220-grain pills. But in reality, you can’t carry a bunch of guns for every possible scenario. So in the described situation, I think having a 10 or 20 round magazine with such subsonic ammunition that won’t cycle the action is actually a benefit. Such ammunition will allow you not only to shoot quietly because it is subsonic but it will also eliminate the sound generated by the reciprocating parts making it as quiet of a gas gun as possible.

    Subsonic Ammunition That Won't Cycle the Action Good or Bad (2)

    Subsonic and supersonic 5.45x39mm cartridges alternated in the magazine

    The beauty of such concept is that you are turning your gas operated firearm into basically a straight pull bolt action rifle by simply using a different ammunition. A simple magazine change will make your weapon suitable for a completely different task. Ideally, for the mentioned task you would need an adjustable gas block with a shut off setting. But then again, not every gun has an adjustable gas block and this looks to be a solution for such firearms.

    Subsonic Ammunition That Won't Cycle the Action Good or Bad (3)

    Detroit Ammo Co. clearly specifies on the package that these loads won’t cycle the action

    What do you think about the above-described concept? Do you think it is realistic or am I playing video games too much? If such situation can happen, is its likelihood high enough to justify carrying a spare 10-rounder of such ammunition? Let’s discuss it in the comments section.

    Hrachya H

    Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience. Hrachya also writes for
    Should you need to contact him, feel free to shoot him a message at [email protected]