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Adams Arms P Series Micro Adjustable Block Piston Kit

03:16
Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, NSN no FGAA-03300
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1
1 of 1 videos
Adams Arms Piston VS DI
Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, NSN no FGAA-03300
1 of 3 images
Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, NSN no FGAA-03300
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1
2 of 3 images
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1
3 of 3 images
EDEMO Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO1

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Questions & Answers
Is this kit supposed to come with a upper receiver bushing? Because I most certainly did not receive one haha or the install tool in the install video Expert Answer

I would recommend contacting the manufacture.
Adams Arms (727) 853-0550

by Ben, Gear Expert, September 22, 2021
See 2 More Answers
Will a faxon bolt for 5.56 work with this carrier? https://www.opticsplanet.com/faxon-firearms-5-56-bolts-bolt-carriers.html Expert Answer

Yes, this will fit under a standard handguard just fine.

by Ben, Gear Expert, September 22, 2021
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
BUY IT - This IS absolutely the setup for 300BO by Mgillee, Verified Owner, December 21, 2023
This IS the kit you want. I originally bought the old style, with two a settings, in the pistol length. It was impossible to get to work right, even with gas port increases in the barrel. 1 year later and this kit presents itself. IT IS PERFECT!!! ...
Read More...
1/2 found this helpful
Helpful Positive Review
Great kit but.... by Mr1218, Verified Owner, May 28, 2020
So this kit is great but. The description should tell you to ensure the gas port on your barrel is at least.125” and you should purchase the Nemo arms 300 blackout buffer spring. I also had to take.035” off of the oprod so the gas block would be full...
Read More...
8/10 found this helpful
Helpful Positive Review
Best upgrade I ever made by wtf, Verified Owner, April 10, 2021
It is almost the same weight as a standard AGB, it's actually quite impressive. Very high quality product. Works flawlessly, no modification to the kit or the op-rod required as others stated. If you are running into length issues - I would modify t...
Read More...
7/7 found this helpful
Most Recent Reviews
Missing parts, can't use it by Pat, February 11, 2024
It showed up missing the mounting screws and optics planet said the manufacturer was sending the parts. Well it's been 4 months now and still no parts.
Most Recent Reviews
Fantastic 300B supersonic by PeterPan, Verified Owner, September 29, 2023
I ran this on a 10 inch SBR using huxwrx suppressor. I used buffers weighting from 1.5oz, 2.2oz, 2.7oz, 3oz, H, H2, H3, H4 I used buffer springs: Carbine, Super 42 braided, NEMO 300B low power spring I used sub ammo that was 208gr and two types of ...
Read More...
Most Recent Reviews
Helped my 8.5” 300 BLK OUT cycle suppressed by DarHan, Verified Owner, March 16, 2023
I installed on my pistol and it works great with a sound suppressor and subsonic loads. It worked with super sonic loads unsuppressed before I installed it. Now I can dial it down for sound suppression and get less recoil and less wear on my upper an...
Read More...
Read All 7 Reviews
Color:
Black
Included Accessories:
Bolt Spring, Drive Rod with Bushing and Lightened Spring, Installation Instruction Card, Patented One-Piece Low Mass Bolt Carrier, P Series Micro Block - Adjustable
Condition:
Used
Condition Quality:
Unknown
Condition Details:
Missing Item

Code: ADA-GCK-AD85I5-FGAA-03300-EDEMO-MI-U

MPN: FGAA-03300-EDEMO

Product No Longer Available

Product Info for Adams Arms P Series Micro Adjustable Block Piston Kit

The Adams Arms Retro-Fit Piston Drive System will convert any standard upper receiver using the same gas port on the barrel. However, instead of directing the gases into the receiver, the gases go into a gas plug and drive rod sleeve that contains the gases and push the bolt carrier rearward to cycle the action. Adams Arms proprietary operating systems mechanically actuate the bolt carrier external of the receiver to keep the internal receiver and all the critical moving parts clean and free from heat and carbon build up. In addition, their proprietary operating systems feature a self-cleaning function. This kit will convert a standard upper receiver from piston operated to gas piston operated. For those wanting to convert a carbine to piston operated, select the correct length conversion kit that will work with 300 BLK and a Pistol Length Gas System.image

Features of Adams Arms P Series Micro Adjustable Block Piston Kit

  • This system will work with 300BLK and a Pistol Length Gas System. Patented One-Piece Bolt Carrier - LOW MASS
  • P Series Micro Block - Adjustable (5 Settings - 100%/74%/53%/32%/11%)
  • Gas Plug
  • Bolt Spring
  • Installation Instruction Card To select the correct length kit, use the following measurements:
  • Pistol: 4.846" from barrel extension to shoulder
  • Carbine: 7.866" from barrel extension to shoulder
  • Mid: 9.866" from barrel extension to shoulder
  • Rifle: 13.241" from barrel extension to shoulder
  • We recommend using a standard barrel nut or barrel nut with similar measurements for proper fit and function of the kit.

Package Contents:

  • Adams Arms P Series Micro Adjustable Block Piston Kit
  • Card link to installation video on site

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Adams Arms P Series Micro Adjustable Block Piston Kit Unavailable & Discontinued Models

List of Unorderable Models

  • USED, Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300 , MPN: FGAA-03300-EDEMO , Code: ADA-GCK-AD85I5-FGAA-03300-EDEMO-MI-U
  • Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300 , MPN: FGAA-03300 , UPC: 812151023865 , Code: ADA-GCK-AD85I5-FGAA-03300
  • USED Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO5, Condition Fair, Installed/Mounted , MPN: FGAA-03300-EDEMO5 , Code: ADA-GCK-AD85I5-FGAA-03300-EDEMO-IN-D
  • USED Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO4, Used, Condition Fair , MPN: FGAA-03300-EDEMO4 , Code: ADA-GCK-AD85I5-FGAA-03300-EDEMO4
  • USED Adams Arms P Series Micro Adjustable Block Piston Kit, Pistol Length 300 BLKOUT Kit, Low Mass Carrier, Black, FGAA-03300, EDEMO3, Condition Fair, Other , MPN: FGAA-03300-EDEMO3 , Code: ADA-GCK-AD85I5-FGAA-03300-EDEMO-OT-D
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Last updated 2026-09-16 UTC.