AR Five Seven Mod. AR57 LEM 5.7x28mm Semi-Auto Rifle - Top-Feed, Downward Ejection, 16 in Fluted Threaded Barrel, 6x 50-Rd Mags
This AR Five Seven Mod. AR57 LEM stands out for its proprietary top-feed system that uses FN P90-pattern magazines and ejects downward through the AR-15 magwell. It features a 16-inch fluted, threaded barrel with a multi-prong flash suppressor, a short receiver top rail behind the magazine, and a railed handguard. Marked "MOD. AR57 LEM" and "AR57 Bellevue, WA," this 5.7x28mm rifle comes with six 50-round magazines and shows very good condition with an excellent bore.
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: There are minor marks from previous handling and use. The bore is bright and clean. Refer to the photos for a closer look at surfaces and markings.
What’s Included
- AR Five Seven Mod. AR57 LEM 5.7x28mm semi-automatic rifle
- Six 50-round P90-pattern polymer magazines
- Polymer angled foregrip (installed)
- Polymer flip-up sight (installed)
The AR57 LEM uses a proprietary top-feed upper that accepts P90-pattern magazines, sending spent cases straight down through the AR-15 magwell. This configuration delivers a 50+1 capacity with the included magazines.
The 16-inch steel barrel is fluted to save weight and threaded for muzzle devices; it is fitted with a multi-prong flash suppressor. The bore is described as excellent with sharp rifling.
A segmented top-rail arrangement—comprising a short rail on the receiver behind the magazine and separate rail sections on the handguard—provides mounting real estate. A polymer angled foregrip is installed, and a polymer flip-up sight is included. The lower is AR-15 pattern with a textured polymer pistol grip and a collapsible polymer stock; length of pull is 11.0 inches.
Construction features include an aluminum receiver with a hard-anodized finish. Markings include "MOD. AR57 LEM" and "AR57 Bellevue, WA." This rifle is made in the United States and operates via a straight blowback, semi-automatic action in 5.7x28mm.