M4E1 Threaded ATLAS S-ONE 5.56 Complete Uppers - Selectable Barrel and Handguard options and Finish

M4E1 Threaded ATLAS S-ONE 5.56 Complete Uppers include the new ATLAS S-ONE Handguard! The S-ONE line of handguards are designed with size and weight in mind, providing the perfect addition to your lightweight build. The proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.

All complete uppers include:

• M4E1 Threaded Upper Receiver
• ATLAS S-ONE Handguard - some configurations have length options
• CMV Barrel - choice of length and gas system
• Barrel option - pinned and welded VG6 Epsilon 556SL option available with 14.5" Black Carbine and Mid-length configurations
• Low profile gas block and gas tube to suit barrel
• This complete upper does not include a BCG or Charging Handle

M4E1 Threaded Upper Receiver Features:

• New enhanced forging that gives the upper receiver a "billet look"
• New picatinny profile that blends seamlessly with the Enhanced Series Handguards
• M4 Feedramps
• .250 takedown pin holes
• Laser engraved T-marks
• Includes port door and forward assist installed

ATLAS S-ONE Handguard Features:

• Front and rear picatinny rail
• Eliminated center of top rail for weight reduction
• Indexing grooves in 12:00 position for positive grip control
• Quick disconnect sling socket at the 3, 6 and 9 o'clock positions
• Compatible with low profile gas blocks
• 1.3" Inside diameter
• 1.5" Outside diameter
• Compatible with mil-spec AR15 upper receivers and barrels

5.56 Barrel Features:

• Chamber: 5.56
• Twist: 1 in 7
• Threading: 1/2"x28
• Material: 4150 Chrome Moly Vanadium
• Finish: QPQ corrosion resistant finish
• Gas Block: .750 (note exceptions below)
• Gas System:  some barrel lengths have choice of gas system
• M4 Barrel Extension
• HP and MPI Tested

Note:

• 14.7" barrels can be pinned and welded with a standard A2 flash hider to yield an overall length of 16+"
• 14.7" Pencil profile barrels require a .625 diameter gas block
• 14.5" barrels with a pinned and welded VG6 Epsilon 556SL yield a 16+" overall length
• The VG6 Epsilon 556SL has a .745" outside diameter, permitting full maintenance and removal of your gas block without having to remove the muzzle device