
Colt's · Carbine
Colt M4 Block II SOPMOD
Gas-operated (direct impingement) · 5.56x45mm NATO · introduced 2009
Also known as M4A1 SOPMOD Block II, M4 SOPMOD Block 2, SOPMOD Block II
About the Colt M4 Block II SOPMOD
The Colt M4 Block II SOPMOD is a select-fire carbine chambered in 5.56x45mm NATO, produced by Colt's Manufacturing Company since 2009. This American-manufactured firearm reflects the engineering traditions and quality standards of its country of origin, designed to meet the demands of both civilian and professional users in a competitive global marketplace. Featuring a 30-round magazine capacity, this carbine offers generous firepower for duty use and home defense. The 14.5-inch barrel maximizes accuracy potential and ballistic performance, making this an excellent choice for target shooting, competition, or field use. At 3175g (112.0 oz), this is a substantial firearm whose weight contributes to reduced felt recoil and enhanced stability during precision shooting. The aluminum alloy frame achieves a notable weight reduction compared to all-steel construction while maintaining the structural rigidity required for safe, reliable operation. This firearm represents its manufacturer's commitment to delivering a well-engineered, reliable product that serves the needs of discerning shooters seeking quality, accuracy, and dependable performance from a proven platform.
The SOPMOD program has been equipping U.S. Special Operations Forces for over 20 years with cutting-edge accessories and modifications that give them decisive advantages in combat. The Block II configuration represents lessons learned from two decades of global special operations, with every component chosen based on real-world combat feedback from the world's most elite warfighters.
Colt M4 Block II SOPMOD specifications
General
- Type
- Carbine
- Action
- Gas-operated (direct impingement)
- Firing mechanism
- Hammer-fired
- Trigger
- Single stage
- Trigger pull
- 3.5 kg (7.6 lb)
- Calibres
- 5.56x45mm NATO
- Magazine capacity
- 30 rounds
- Magazine
- Detachable box magazine
Dimensions
- Barrel length
- 368 mm (14.5 in)
- Overall length
- 813 mm (32.0 in)
- Folded length
- 813 mm (32.0 in)
- Weight (empty)
- 3.17 kg (7.00 lb)
- Weight (loaded)
- 3.75 kg (8.26 lb)
Barrel
- Rifling twist
- 1:7 in (178 mm)
- Rifling
- Right hand
- Grooves
- 6
Materials
- Barrel
- Steel
- Receiver / frame
- Aluminum alloy
- Stock
- Polymer
- Finish
- hard_anodized
Performance
- Muzzle velocity (typical)
- 914 m/s (2999 fps)
- Muzzle energy (typical)
- 1670 J (1232 ft·lb)
- Effective range
- 500 m
History
- Introduced
- 2009
- Production status
- In production
- Country of origin
- US
- Designer
- Eugene Stoner
Features
- Collapsible stock
- Select fire
- Daniel defense ris ii rail
- Chrome lined barrel
- Chrome lined chamber
- Rotating bolt
- Flat top receiver
- Picatinny rail
- Sopmod accessory kit
- Mk12 gas block
- Surefire warcomp muzzle device
Safety
- Manual safety selector
- Half cock notch
The Block II designation represents the second generation of the SOPMOD program which began equipping SOF units in the late 2000s. The 14.5-inch barrel is pinned and welded to meet NFA requirements for civilian legal configurations, though military versions use the shorter barrel with appropriate tax stamps. The Daniel Defense RIS-II rail became the standard handguard for SOPMOD Block II uppers, replacing earlier rail systems. The weapon maintains the M4A1's full-automatic capability and improved heavy barrel profile for sustained fire. SOPMOD accessories are modular and mission-configurable, with over 90 approved components in the Block II kit.
This is a variant of the M4A1 Carbine.
Similar models

Aero Precision M4E1 Complete
Gas-operated (direct impingement) · 5.56x45mm NATO

Colt LE6920
Gas-operated (direct impingement) · 5.56x45mm NATO

AR-15
Gas operated short stroke · 5.56x45mm NATO

Berdan I M1868
10.75x58mmR Berdan

Colt AR-15 Sporter (SP1)
Gas-operated (direct impingement) · .223 Remington

Colt Burgess
Lever action · .44-40 Winchester

Colt Burgess Rifle
Lever action · .44-40 Winchester

Colt CAR-15
Gas-operated (direct impingement) · 5.56x45mm NATO