Commando Barrel Assembly - Pinned XM177 Flash Hider with 12.5" barrel

sometimes in stock, sometimes made to order, could have a wait time of up to 5 weeks
Extremely Limited Production and Availability:
We are getting different barrels in every month, but usually only one brand per month.

Commando 12.5" Barrel Assembly With XM177 Flash Hider


CAR-15 16" barrel assembly with pin and weld of an XM177 flash hider to a premium 12.5" barrel

Here at Charlie's, our love of clones encompasses all military rifles. Because there are so many variants of the CAR-15, we asked Potomac Armory to put together a kit for our customers who want a non-NFA barrel option. They started by cutting down a government M4 contour 14.5" FN or Colt barrel to 12.5". It retains the carbine gas system and the traditional A-frame type front sight base, and the barrel smiths open the gas port a smidge since the barrel is getting shortened. The muzzle device is a XM177 flash hider. This is pinned and welded to bring the total barrel length above the 16" mark. The delta ring assembly is pre-installed, and a set of Colt "skinny" handguards round out the package.  Yes, 6 holes.  Charlies does the hard part of sourcing all the right parts and working with Potomac Armory, this barrel assembly is made with genuine parts and the art of love.


  • Colt or FN Government / M4 profile barrel, 12.5" cut-down and gas port opened (16+ inches when flash compensator is pinned)
  • 4150 CMV steel alloy with Parkerized exterior finish
  • 1:7 twist, chambered in 5.56 NATO
  • Chrome Lined
  • factory installed "F" height front sight base with sigh pins
  • Flash compensator, 4" length, forged steel and phosphated black, professionally pined to barrel
  • Skinny polymer single insulated CAR carbine handguard with 6 holes
  • Colt USGI barrel nut and delta ring assembly
  • Carbine length gas tube, either Colt or Remcon North

When the topic legendary special forces comes up, several units come to mind. Those who are only slightly acquainted with the topic may bring up the Navy SEALs or Delta Force. People more familiar with the topic will mention Marine Raiders or Airforce PJs. One unit that gets left out of many of these discussions is MACV-SOG, the Military Assistance Command, Vietnam – Studies and Observations Group. SOG units worked behind enemy lines on a variety of mission types, utilizing new equipment and tactics that would become the standard in future conflicts. A weapon that was ubiquitous with Vietnam era SF was the CAR-15, aka the Commando. This short barreled variant of the M16 would set the pace for all future carbine variants. While multiple weapons would be called Commandos, one common feature was the distinct muzzle device.

Maybe you will build an XM177 or a R609.  This barrel gives you a head start.

Note on front sight base (FSB):  There is a lot of talk and debate around whether the carry-handle upper receiver (A1/A2) with a carbine length gas system had a standard or a taller "F" height.  Honestly, it becomes at times a technical piece of history that is hard to identify who did what and when, and more importantly, does it really matter?  In the clone-building community, these issues get hotly debated.  First, to put this in perspective, the height difference is 0.04".  If you line up each FSB to another, can you see the difference?  Yes, but barely.  It is between 1/16th and 1/32nd of an inch.  Imagine that on ruler.  But, the best information that we, at Charlie's Custom Clones has found is that only the 20" rifles had different sight bases, and when the carbine gas system was introduced in the 1960s, the FSB was increased by 0.04" to provide for better sighting.  Is this correct?  We are not 100% sure, but we think so.  What this means is that all carbine gas systems, whether used on an A1 and A2 carry handle receiver, or on an A3 or M4 flat-top receiver should use the higher height, "F" size FSB.  The actual stamping or engraving of the "F" seems to have not occurred until later when the M16A4 was introduced, as there could be confusion between the 20" barrels.  So, we are using the "F" or standard, higher height FSB with this barrel assembly.