This contract overrun upper receiver is built around the M4E1 Enhanced upper receiver and is powered by a superlative arms gas piston system. This gas system offers a range of adjustments and provides a different operating system that results in less upper receiver fouling than traditional direct impingement systems.
This upper receiver includes a pin and welded VG6 Epsilon 5.56 muzzle device providing a decrease in muzzle rise and recoil with the added function of bringing the overall barrel length to 16".
INCLUDES:
M4E1 Enhanced Upper Receiver
12.7" Enhanced Handguard
Dimpled 14.5" 5.56 CMV Mid-Length Barrel
VG6 Epsilon Muzzle Device (Pinned and Welded)
Superlative Arms Mid-Length Piston System
Assembled BCG w/ Superlative Arms Piston Bolt Carrier
Aero Precision Ambidextrous Charging Handle
M4E1 UPPER FEATURES:
Forged from 7075 T6 aluminum
Precision machined to M4E1 specs
M4 feedramps
Matte black hard coat anodized Mil 8625 Type 3 Class 2
Laser engraved T-marks
Comes assembled, with port door and forward assist installed
Accepts standard AR15/M16 components
Handguard mounting platform is forged into the receiver
Works with Aero Precision handguards but also fits most BAR-system handguards
Barrel nut and wrench are included
 
GEN 2 ENHANCED HANDGUARD FEATURES:
1pc free float design
Built in anti-rotation tabs
Scalloped rails
Continuous top rail
1.78" inside diameter fits most muzzle devices and 1.5" suppressors
Compatible with low profile gas blocks
Quick disconnect sling socket at the 3, 6 and 9 o'clock positions
Additional milling along flats to aid with gripping and add visual appeal
New profile for the continuous picatinny top rail
14.5" 5.56 MID-LENGTH BARREL FEATURES:
Chamber: 5.56
Length: 14.5"
Twist: 1 in 7
Threading: 1/2"x28
Material: 4150 Chrome Moly Vanadium
Finish: QPQ corrosion resistant finish both inside and out
Gas Block Journal: .750
Dimpled Gas Block Journal
Gas System Length: Mid
Weight: 26oz
M4 Barrel Extension