Colt ACC-M (Advanced Colt Carbine-Monolithic): 21st Century M4/M4A1 Carbine

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By David Crane
defrev at gmail dot com

November 4, 2008

So far, DefenseReview has covered the Colt SCW (Sub-Compact Weapon), Colt APC (Advanced Piston Carbine) and Colt AHC (Advanced Hybrid Carbine), but those aren’t the only newly-developed weapons in Colt Defense’s bag of tricks. If you’re interested in an upgraded/modernized version of the standard, direct-gas-impingement (DGI) Colt M4A1 Carbine, Colt Defense has two weapons for you, the Colt ACC (Advanced Colt Carbine) and Colt ACC-M (Advanced Colt Carbine-Monolithic) select-fire carbines.

The Colt ACC adds some of Colt’s new components/features and accessories that we’ve already covered. These include the:…


– Colt Mil-Std-1913 Flat-Top Upper Receiver with ARS

– Colt Gas Regulator Sleeve a.k.a. Gas Impingement Sleeve (Patent Pending), which compensates for gas port erosion and maintains a lower cyclic rate of fire (ROF).

– Optional Folding Titanium Front Site a.k.a. Flip-Up Front Sight/BUIS, which reduces weight on the barrel, improving accuracy and zero retention.

– Buttoned or Cold Forged Barrels, which are capable of exceeding 15,000 rounds before replacement.

– Colt Pivot-Forward Extractor – The "pivot forward design" increases hold on the cartridge case during hard extraction and full-auto fire.

– Enhanced Dust Cover "Wiper", which automatically covers the ejection port cover, and eliminates the need for a manual dust cover/ejection port cover.

– Optional Colt Grip Laser (CGL) vertical foregrip with "travel light" and visible laser that can operate in both pulse mode and constant laser mode.


The Colt ACC-M (Advanced Colt Carbine-Monolithic) just adds Colt’s proprietary Mil-Std-1913 "Picatinny" monolithic rail system (quad rail)/forend rail tube to the mix.

The cool thing about the Colt ACC is that existing Colt M4 Carbines and Colt M4A1 Carbines can be easily and relatively inexpensively modified/upgraded into Colt ACCs, which is more cost-effective than completely replacing the weapons with a whole new carbine with different control layout and overall ergonomics and handling characteristics that requires new and different training and maintenance protocols.

Even converting existing M4s and M4A1s to the Colt ACC-M configuration is more cost effective, since you only have to replace the upper receiver rather than switch to a whole new weapons system, and all current controls and handling characteristics, training and maintenance remain the same.

It would seem logical that the Colt Commando (11.5" barrel) and Colt M4 CQBR (10.3" barrel) can also be converted/upgraded/modernized to the new Colt ACC configuration.


Company Contact Info:

Colt Defense LLC
547 New Park Ave
West Hartford, CT, 06110
800-241-2485 Toll Free
860-232-4489 Office
860-244-1442 Fax
http://www.colt.com/mil/home.asp Website


Related Articles:

Colt IAR (Infantry Automatic Rifle) Assault Rifle/SAW Hybrid Weapon (Photos!)

Colt Advanced Hybrid Carbine (AHC): Gas-Impingement/Gas Piston Hybrid Weapon

Colt Advanced Piston Carbine (APC): Meet Colt’s New Piston-Driven HK416 Killer

Colt Sub-Compact Weapon (SCW): Folding-Stock Tactical 5.56 SBR (Photos!)

Sources Sought: ‘Improved Carbine and Subcompact Individual Weapon System’

FERFRANS Gas Piston/Op-Rod SOAR Tactical AR-15 SBRs for Special Operations

FERFRANS Ultra-Concealable Piston-Driven 6-inch AR Subcarbine/SBR (Video!)

FERFRANS Combat Rifles and GRSC Combat Rifle Scope (CRS) at the Range


Acronyms and Abbreviations used in this article:

Full-Auto – Fully-Automatic
BUIS – Back-Up Iron Sight

Colt ACC-M (Advanced Colt Carbine-Monolithic): 21st Century M4/M4A1 Carbine by

About David Crane

David Crane started publishing online in 2001. Since that time, governments, military organizations, Special Operators (i.e. professional trigger pullers), agencies, and civilian tactical shooters the world over have come to depend on Defense Review as the authoritative source of news and information on "the latest and greatest" in the field of military defense and tactical technology and hardware, including tactical firearms, ammunition, equipment, gear, and training.

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