Allegiance Ammunition SilentStrike Subsonic .223

When prospective suppressor owners mention looking for subsonic .223 ammunition, my first impulse is to say “novelty” or “expensive .22lr”. After all, achieving low velocities is usually accomplished by anemic powder charges or heavy bullets. The later, fitting anything over ~80 grains in a 223 Remington case, is a challenge. However, Allegiance Ammunition is selling the SilentStrike – a 110gr frangible .223 round That never breaks the sound barrier.

Granted, 110 grains is about half of the weight of a standard 300 Blackout round, the current king of AR15 rifle suppression. On the other hand, the bullet weight is about double that of a standard .223 round. Meaning even though the velocity isn’t there, the extra mass should help with terminal ballistics.

Like most longer bullets, a higher rate of twist is favored for better accuracy. I’d like to get a better look at the projectile and possibly a gel test before using the SilentStrike for any serious work. However I’d love to hear and see some run through a suppressed AR.

Details below.

SilentStrike .223

SilentStrikeTM is the worlds only full functioning 223 subsonic round that will operate the AR and M4 weapon platform at 975 FPS in semi and full auto.

SilentStrikeTM uses a dense compressed powder metal core to achieve bullet densities that allow the round to generate sufficient gas pressure to operate the gun.

SilentStrikeTM can be engineered to act as a solid if penetration is needed or as a frangible if fragmentation is needed for greater tissue damage. A 1×7 twist is required for best results. It will work at a limited range in a 1×9 but will not be as accurate at the longer ranges. No modifications to the host weapon is needed. SilentStrike is based upon a stock factory spec which is a H buffer, stock recoil spring and a min .065-.070 gas port.

SilentStrikeTM delivers whether the user is a varmint hunter, law enforcement personnel, or part of a covert team needing astonishing stealth combined with maximum power and performance.



Ridge Road Outdoor Marketplace


Whether a law enforcement or military team that needs astonishing stealth combined with maximum power and performance, SilentStrike™ delivers. SilentStrike™ fully functions in semi and full auto in the M4, AR, H&K 416 weapons platform at a silent 1050 FPS. No modification to the weapon is needed. SilentStrike™ is available in a solid lead core, lead powdered metal, and tungsten core. The fragmenting SilentStrike™ core gives excellent results in soft tissue even at sub-sonic velocities. Can also be produced in the Covert, non-cycling configuration.



SilentStrike L (SSL)223 97gr is a fully functional subsonic round that is more economical to shoot than the SST which is our Tactical frangibleTungsten powdered metal core. The SSL is a jacketed NON frangible designed to function the M4, AR15 at 1020 FPS. Not only is this round great for target shooting it also an effective hunting round.


LE – Science – OSINT.
On a mission to make all of my guns as quiet as possible.
Twitter: @gunboxready
Instagram: @tfb_pete


  • G B

    I’m interested simply because it’s a subsonic .223 load that will cycle an AR. I’ve heard that loads like that exist but haven’t been lucky enough to come across one.

    Also a mag of quiet, frangible ammo would be nice to have around for critters that manage to find their way into the garage or the attic space above it.

    • Pete – TFB Writer

      Same here. I’d like to buy enough for testing and one magazine, just because.

  • James Ivy

    Definitely a critter getter but like any subsonic 223 rounds now or ever it will never be a choice for defense/offense , I load up 225-55-lfn gc under 2.5-3 gr of trailboss for my Ruger American ranch it puts me at around 1020 and has been great for dispatching crows and chipmonks but at the same time keeping my neighbors from calling the cops. Btw I’m in Alabama with plenty enough land to shoot and do it safely but it seems Everytime I shoot the cops are called from the same people the cops know me pretty well now and I usually have a glass of sweet tea for them when they arrive that makes my neighbor soooooo mad.

  • Joe

    I’m looking forward to a couple of gel tests. Seems close to .38 Special in weight and velocity, without having to adopt a different caliber/upper.

  • Sianmink

    “Can also be produced in the Covert, non-cycling configuration.”
    Translation: this is one of the tests that didn’t work, but we’re gonna try to sell it anyway.

  • Stand Your Ground

    the bullet weight is about double that of a standard .233 round.

    • Pete – TFB Writer

      Yikes. Those .233’s are nasty.

      Fixed. Thanks.

      • Beju

        I stick with .9mm

        • Pete – TFB Writer

          Quite a sting those things have.

    • Pete – TFB Writer

      Yikes. Those .233’s are nasty.

      Fixed. Thanks.

  • feetpiece _

    Le Mas APLP all over again.

  • Edeco

    Fran-gee-blay… must be Italian.

    Seriousely, I used to think faster twist hurt muzzle velocity, but I found a test where there was no discernable effect. However it’s supposed to make shorter bullets go nose-high so I wonder if there’s practical loss of retained velocity at some distance…

    • Cyborg Fred

      Works wonders with copper and bonded bullets. Faster than normal twist rates and short barrels.

    • Pete – TFB Writer

      Perfect leg lamp reference. 3 TFB points.

  • I think you’d probably get more terminal effect from just firing the entire .223 cartridge at someone out of a wristrocket slingshot.

  • Cyborg Fred
  • XT6Wagon

    but how will the tacticool crowd injure themselves if they can’t feed .300 ammo into a .223 gun?

  • Renato H M de Oliveira

    110 grains subsonic frangible (not HP/SP) @ 1000ish fps.
    Less performance and less diameter than a 38 Special.
    Why bother?

  • noob

    Weren’t “blended metal bullets” a big thing back in 2003?

  • ToddB

    I know some say ‘whats the point why not just use a 22LR’? Well 22LR you can really only get up to 40gr, yes they have those Aguila 60gr but requires a fast twist barrel. I could sit here and pick at the ‘anemic’ 300AAC since it only uses a 230 gr bullet, I can use 500gr in my 45-70. But I can’t exactly feed 30 rounds thru my 45-70 in semi auto. I do not have nor intend to buy a 300blackout. But there is a use for subsonic 223. Not a ton of uses, but some.

    When it comes to subsonic, weight is where its at. Nice this one uses a 100gr bullet, presume it works in a 1-9 twist. No its not a 300AAC, but you could shoot these with a mag change. And nice they cycle the weapon. I did manage to find a good accurate subsonic 223 load, but certainly won’t cycle. I went with cast as jacketed just does not do well at this velocity. A 70gr works really well, and use a gas check the same mold can be used full power. I tried the various powders other have used. Trailboss works the best, sort of. It did work, but large velocity swings between shots, like 250fps, which really kills any accuracy. Tried titegroup and some others, but worse results, one was fine the next barely made it out the end of the barrel. I have not needed to enlarge flash holes for 30 cal subsonic or bigger. But that was the only way to get subsonic 223 to work. I dremel a cut on the rim so I know they are drilled. Actually pretty accurate once you get them working right. And really really quiet thru a can.

  • redsr

    ~100 grs is about the minimum for 12″ bare gel block penetration for handgun bullets… A 22 cal vs 9mm/.380 cal bullet would presumably allow for greater penetration depth for less weight for the 22 cal.

    Also worth remembering that flat base bullets w/in 200 yards are more accurate than boattail. Not certain of case here, but short range subsonic bullet “desirables” are quite different than for supersonic rifle rounds with much greater effective range…