This system will work with .223/5.56 x 45 mm NATO. For other calibers, please contact Support.

Kit includes:

Patented One-Piece Bolt Carrier

P Series Micro Block - Non-Adjustable

Bolt Spring

Drive Rod with Bushing and Spring

Installation Instruction Card

Our Piston Kits No Longer Require the Receiver Bushing or Installation Dowel





The Adams Arms Piston System:

A short stroke free floating piston system.

Is Self-Cleaning.

Carbon and gases are expelled forward, away from operator.

Corrosive resistant coating processes.

Harmonics are not transferred into the barrel.

Doesn't vent directly to atmospheric pressure; this eliminates flash signature and super sonic crack which is optimal for night vision and suppresses fire.

Has a Lifetime Warranty.

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. Many aftermarket proprietary barrel nuts do not offer the clearance for the drive rod or proper seating of the spring and bushing.

Micro Gas Blocks should have the set screws torqued to 87 in-lbs

Installation Instructions: CLICK HERE

This is a clearance/final sale item