Grey Ghost Precision Cornerstone AR-15 Custom 5.56 NATO Rifle — 16.5" JAKL Piston Upper, ACR Folding Stock, Pinned & Welded Flash Hider
This Grey Ghost Precision Cornerstone build combines a Palmetto State Armory JAKL 16.5" long-stroke piston monolithic upper with a Bushmaster/Remington ACR Enhanced folding telescoping stock, creating a buffer-less, side-charging AR-pattern rifle that folds flat without tools. A pinned and welded 3-prong flash hider brings the barrel to a non-NFA overall length, while the Grey Ghost lower’s tensioning screw ensures a tight, rattle-free fit. The result is a durable, modular platform ready for suppressed or unsuppressed use with its 8-position adjustable gas block.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Specific Condition Notes: Light surface scratches and finish blemishes are visible on the receivers and handguard, but all controls operate smoothly. The bore is clean and shiny with no pitting.
Bore Condition: Good — clean, well-maintained, minor wear marks.
Bore Rifling: Good — intact, well-defined lands and grooves.
What’s Included
• 5 × Magpul PMAG GEN M2/M3 30-round polymer magazines (mix of windowed and non-windowed versions)
The PSA JAKL upper uses a captured recoil assembly inside its 6105 aluminum monolithic receiver, eliminating the traditional AR buffer tube and allowing the ACR stock to fold and lock securely on either side. The rifle stays fully functional when folded, offering compact storage and quicker deployment.
A reversible, non-reciprocating side-charging handle gives the shooter ambidextrous control without disturbing optics on the Picatinny top rail. The full-length M-LOK handguard offers ample real estate for accessories and maintains a continuous upper rail for uninterrupted sight mounting.
The long-stroke gas piston system reduces fouling in the action and features an 8-position tool-free adjustable gas block, letting the user fine-tune performance for standard, suppressed, or adverse conditions. The pinned & welded 3-prong flash hider meets the 16" minimum length requirement while minimizing muzzle flash.
The Grey Ghost Precision forged 7075-T6 lower includes an integral tensioning screw for a tight upper-lower fit, a flared magwell for faster reloads, and a Magpul MOE pistol grip. Combined with the ACR’s 7-position length of pull, adjustable cheek riser, and rubber butt-pad, the rifle can be tailored quickly to different shooters or shooting positions.