Built for compact performance and dependable cycling, the MICRO AR15 5" PISTOL KIT bundles matched components that simplify short-barrel builds. The forged flat-top M4 Mil-Spec upper (7075-T6), precision 5" 4150 chromemoly barrel (1:5 twist), and MICRO gas system deliver reliable function across common loads. A 4" free-float M-LOK handguard and nitride, case-hardened BCG reduce weight while improving durability. A “Stay Spooky” dust cover and Charging Handle to complete the look.
This kit ships largely assembled so you can finish your pistol quickly and get to the range. Ideal as a truck/pack gun, compact defensive platform, or a fun micro build with attitude.
Key Features
-
Forged flat-top M4 Mil-Spec upper receiver (7075-T6 aluminum)
-
MICRO 5" 5.56 NATO barrel — 4150 chrome-moly, 1:5 twist, pistol/micro gas system
-
4" free-float M-LOK handguard (low-profile)
-
Bolt Carrier Group — 8620 case-hardened, nitride finish, staked gas key
-
Cerakote charging handle, forward assist, dust cover, and thread protector
-
Includes: “Stay Spooky” dust cover and charging handle for seasonal style
Specs
-
Barrel: 5" 5.56 NATO, 4150 Chrome Moly
-
Twist Rate: 1:5
-
Gas System: MICRO (pistol-length)
-
Handguard: 4" free-float M-LOK
-
BCG: 8620 case-hardened, nitride finish
-
Compatibility: Standard Mil-Spec AR-15 lowers
What’s Included
-
Forged flat-top M4 Mil-Spec upper (assembled)
-
Installed 5" barrel & MICRO gas block/system
-
4" free-float M-LOK handguard (installed)
-
Bolt Carrier Group (installed)
-
Charging handle (installed)
-
Forward assist & "Stay Spooky" dust cover (installed)
-
Thread protector / muzzle protector (installed)
-
Lower Parts Kit (LPK) and buffer assembly when listed on SKU — check product page for bundle details
What’s NOT Included
-
Stripped lower receiver (serialized). AR15-Overstock does not sell or transfer stripped lowers.
Why Buy This Kit
-
Matched components reduce the guesswork and compatibility issues common to short-barrel builds.
-
5" barrel gives a balance of compactness and more forgiving gas tuning vs. ultra-micro barrels.
-
Ships mostly assembled for fast, easy builds.
-
Seasonal styling option adds character without compromising performance.