M4A1 Geissele USASOC Upper Receiver Group, URGI, CLONE CORRECT, 14.5" Potomac 2023 Production

$1,499.00 - $1,839.00
Assembled to Order, Ships in 2 to 5 weeks

Geissele Upper Receiver Group, USASOC URG-I with pinned flash hider


This is the current production, Military Clone Correct Upper Receiver Group, with Colt and Geissele correct components

Now available with Surefire SOCOM WarComp 3-prong, SOCOM WarComp Closed-Tine, SOCOM 4-prong, Extended A2, or no muzzle device.

The US Army Special Operation Command is changing out the M4 upper receivers with this new improved model, which features the Geissele Mk16 DDC rail, and a Daniel Defense 14.5" Government profile mid-length barrel

Note:  This product originally came to market with Charlie's and Geissele collaborating to bring a military correct upper receiver group.  Geissele exited the clone-correct market in late 2018, and Charlie's now has this model assembled by Potomac Armory, with all genuine Colt and Geissele and other military-correct components.  This is as close as you get to what the US Army is issued.

Each URGI is fitted with the handguard Geissele designed specifically for USASOC, the MK 16 M-LOK™ Super Modular Rail handguard with a full-length Picatinny top rail and lots of slots for other accessories. T-markings are engraved on the rail but not painted white to help keep the rifle unobtrusive.


  • Colt M4 upper receiver with forward assist, shell deflector & ejection port cover, currently sourcing Colt upper receivers without CAGE Code markings, complete with M4 feed ramps and interior dry lube treatment.  
  • Geissele Mk16 Super Modular Handguard with Geissele roll-marks in DDC
  • FN military grade barrel - chrome-lined and phosphated steel 14.5" CHF barrel with 1-7" rifling & 1/2"-28 tpi muzzle threads and mid-length gas system
  • Geissele Airborne (military version with roll-marks) DDC charging handle
  • Mk12 gas block
  • Colt M16 bolt and carrier group
  • Surefire flash hider, pinned and welded, with your choice of SOCOM WarComp 3-prong, SOCOM WarComp Close Tine, SOCOM 4-prong, or Extended A2.

Note:  if you select Surefire SOCOM WarComp, we time this as neutral (ports pointed up).  If you want it timed to the starboard side, please make sure to put that in the comments.  Both are correct.  Our gunsmiths prefer ports timed up.

Production note In 2018 Geissele was manufacturing this, but stopped offering the clone-correct URGi.  In 2020, Potomac Armory took over the build from the exact same components that Geissele used:  factory Geissele, Surefire, Colt and Daniel Defense parts.  All the same product, but not shipped in a Geissele box, as this is no longer a Geissele factory product.  Potomac Armory and Charlie's Custom Clones are factory dealers and OEM (original equipment manufacturers), and are using 100% authentic parts, and nothing fake substituted. In 2021, the Daniel Defense barrels became impossible to obtain, and FN barrels have been substituted.  Note:  Both FN and DD barrel makers are using the same 4150 CMV phosphated coated steel, the same chrome-lining.  These are all military grade barrels.  

Note:  This barrel, with a pinned and welded flash hider will measure over 16" so it will be "street legal," and will not require NFA registration as an SBR when mounted on a lower receiver as a rifle.

Note on Surefire muzzle devices:  The SOCOM versions of flash hiders will support the Surefire SOCOM family of suppressors.  Also, any of the Surefire muzzle devices will fully function without a suppressor.

Note on pictures:  The pictures below contain shots of pre-production prototypes, as well as versions that may have been offered in the past and are no longer offered.  Charlie's updates pictures from time to time.  Please refer to the specifications above, which are the most accurate we have at this time.