Adams Arms Releases 300 Blackout Piston Guns

As an owner of an Adams Arms piston rifle, I can say that I love my piston rifle.  It is reliable and eats just about everything I shoot without fail. When I started a .300blk build a few months back, I was looking at having my gunsmith convert a standard Adam’s Arms kit to .300blk.  Now Adams Arms has released a new .300blk line, with uppers in both 14.5″ and 9.5″ barrels.  Both are also also available as complete firearms.

No word on if they plan to make a conversion kit that will be .300blk compatible, right now their site only lists 223/556 conversion kits.  I would hope that they would release a conversion kit in the near future for those building their own uppers.  Here is the press release from Adams Arms.

Adams Arms is very proud to introduce their new line of piston driven 300BLK products, complete with the Adams Arms legendary Lifetime Warranty and accuracy guarantee. Our new line of piston driven 300BLK uppers and pistols are available in multiple configurations and barrel lengths with the same clean running, reliable system you have come to expect from Adams Arms and the accuracy and durability of Voodoo Innovations Melonited barrels, combined with the benefits of the .30 caliber 300BLK cartridge.

Adams Arms 300BLK uppers and pistols are perfect for your home defense, hunting, and sporting needs, where you need more punch than 5.56/.223 can provide, while maintaining low recoil and flash signature benefits of 5.56 in a compact AR design.

One of the main benefits of the 300BLK cartridge is shooting suppressed to increase reliability and reduce sound signature. The Adams Arms piston systems include adjustable gas blocks for your various shooting applications and to accommodate a wide range of subsonic and supersonic ammo. The XLP gas block gives the shooter the ability to fine tune their rifle. The Adams Arms piston systems run cleaner and cooler, offering a more reliable option for shooting suppressed without extreme fouling or carbon build up resulting in failures.


  • Jeff S

    I too, love my AA piston upper (11.5″)… I had been thinking about trying out .300BLK – this might push me over the edge. Now to file the paperwork for my SBR – the 9.5″ could be awesome.

  • Jeff S
  • Mack

    haven’t people been using aa piston conversions on rounds other then .223? or am i mistaken? i have a .223 aa piston conversion and it is amazing, but beings i think i will never have a DI gun again specially with xlp being released, it would be neat to be able to have it in different calibers.

  • Dual Sport

    I have read numerous times a reliable piston system that works with the 300 is not yet out there. Perhaps this it?

    I wonder how well all those 5.56 piston rifles and conversion kits are holding up today? Carrier tilt issues ever resolved? AA has had their product in the field for several years now.

    Were they ever accepted by the military? Any comparisons to the HK416 system?

  • ValleyForge77

    Why the 1:9.5 twist rate, I wonder? If it was 1:7, I’d already have one on order. Instead I have to wait now and see some independent reviews to get an idea of accuracy with 1:9.5 (and a short stroke piston)

    • ValleyForge77

      Oh, and how long is the pistol buffer tube and is the castle nut staked? (want to see how it will pair up with an SB-15 as far as LOP, or if another pistol buffer tube is easily swappable). I also see mention of an accuracy guarantee, but can find nothing in regards to what that actually is. Dammit, I’m trying not to just take a flyer on this and get an independent review first, but getting real itchy. Have some questions as you see. Don’t know much about voodoo barrels ….and of course 300 BLK piston is pretty cutting edge. XLR looks pretty awesome with 5 adjustments. Curious about the Samson evo. Would have to swap the VDI comp to a 51T. Awww hell, I might end up writing my own review first, dammit.