PSA M4A1 Carbine 5.56 NATO AR-15 with Adams Arms Piston, 16 in Barrel, Samson KeyMod Handguard, Hiperfire Trigger
This PSA M4A1 Carbine is a customized, piston-driven AR-15 built around a PSA lower featuring the iconic "PROPERTY OF U.S. GOVT." roll mark and three-position SAFE-SEMI-AUTO selector markings. It is outfitted with an Adams Arms short-stroke piston system, a Samson Evolution EX Series 12-inch KeyMod free-float handguard, a Hiperfire trigger with Hiperfire angled safety, and an Epsilon EG6 multi-port muzzle brake. A WARNE one-piece scope mount, MFT collapsible stock, and Strike Industries charging handle round out a well-specified, matte-black, US-made carbine.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: This firearm is in great shape. There are minor, superficial scratches and blemishes present.
What’s Included
- 1x 30-round Magpul PMAG polymer magazine
- Two-point rifle sling (installed)
- WARNE one-piece scope mount with rings (installed)
- Samson Evolution EX Series 12-inch KeyMod free-float handguard (installed)
- Adams Arms short-stroke piston system (installed)
- MFT collapsible carbine stock (installed)
- Anti-rotation trigger/hammer pins (installed)
- Multi-port muzzle brake/compensator (installed)
Built on a PSA M4A1-pattern lower, this carbine combines AR-15 familiarity with a short-stroke piston operating system from Adams Arms. The upper is a flat-top Picatinny design with forward assist and ejection port cover. It feeds from STANAG-pattern magazines and is chambered in 5.56mm NATO with a 30+1 capacity.
The Adams Arms piston kit includes an Adams Arms-marked piston gas block, delivering a piston-driven action in place of a standard direct-impingement setup. A Samson Evolution EX Series 12-inch KeyMod free-float handguard provides a rigid, lightweight aluminum interface for accessories.
Controls and fire-control components are upgraded with a Hiperfire trigger, Hiperfire angled safety selector, and anti-rotation/anti-walk (anti-roll) trigger and hammer pins. Selector markings are the classic SAFE-SEMI-AUTO style, and the rifle uses a manual safety.
Externally, the 16-inch threaded barrel wears an Epsilon EG6 multi-port muzzle brake. A Strike Industries charging handle, MFT collapsible carbine stock, and a rubber overmolded finger-groove pistol grip enhance handling. A WARNE one-piece scope mount with rings is installed, and a two-point sling is included. Receivers are aluminum alloy with a matte black hard-anodized finish, and the rifle is made in the United States.