There’s a world of options when it comes to AR15s, and for those that want to reach out to further targets or hunt with 5.56, the 18-inch ENDEAVOR® Mk4 chambered in 5.56x45mm is an awesome choice. Despite all the different caliber offerings available today for AR15 pattern rifles, 5.56x45mm still stands as one of the most popular.
Built on our Mk4 – AR15 platform, this ENDEAVOR can make use of just about any AR15 compatible component, and utilizes a nitride-finished 18-inch 416 stainless steel barrel for enhanced ballistic performance.
Each CMMG® ENDEAVOR rifle is purpose-built for long-range performance, with everything from the Magpul® MOE® rifle stock to the ZEROED™ muzzle brake, and every part in between selected for its utility to the avid marksman.
The EML™ 15 handguard maximizes customization potential. M-LOK® attachment slots at the 12, 3, 6, and 9 o’clock positions give you plenty of real estate to mount accessories, while the Picatinny rail sections allow for easy and solid mounting points for sights and accessories.
CMMG Endeavor MK4 5.56mm 18" Barrel 30 Rd Armor Black
Platform: Mk4
Caliber: 5.56X45mm
Operating System: Direct Impingement
Barrel Length: 18
Barrel Twist: 1:7
Barrel Contour: Mt
Barrel Material: 416Ss, Sbn
Barrel Twist: 1:7
Muzzle Device: Cmmg Zeroed Muzzle Brake
Muzzle Thread: 1/2 X 28
Gas Port Location: Rifle
Gas Block: 0.750 Non-Adjustable
Upper Receiver: Billet 6061 T6 Aluminum
Lower Receiver: Mk4 Forged 7075 T6 Aluminum
Hand Guard: Cmmg Eml15 M-Lok
Finish: Cerakote
Charging Handle: Cmmg Zeroed Ambi
Pistol Grip: Cmmg Zeroed Pistol Grip
Buffer Typel: Rifle/A1, Ar15
Receiver Extension: A1
Stock / Brace: Magpul Moe Rifle Stock
Trigger Type: Zeroed Drop-In
Trigger Guard: Cmmg Zeroed Trigger Guard
Safety Selector: Cmmg Zeroed 60/90 Degree
Magazine: Magpul 30Rd Pmag
Weight: 7 Lbs
Length: 37.8"
Caliber Dictionary
The Below Information Has Been Provided From Our Gun Caliber Dictionary And Is Meant For Informational Purposes Only. It Is Not Intended to Describe The Unique Specifications For This Ammunition.
The 5.56X45mm NATO cartridge was designed by James Sullivan, a member of Eugene Stoner's engineering team that developed both the M16 rifle and its original cartridge. The 5.56X45mm NATO was adopted by the U.S. military in 1964 and by NATO in 1980. With bullet diameter of .224-inch, the original M193 military cartridge used a 55-grain bullet at 3250 fps; the current M855A1 cartridge, developed by FN, uses a 62.5-grain bullet at 3020 fps, offering greater range and better penetration. The civilian version of the 5.56X45mm is 223 Remington; the cartridges are dimensionally identical but military chamber dimensions and specifications for military brass are different. It is considered safe to use 223 Remington ammo in a 5.56X45MM NATO chamber, but not a good idea to use 5.56X45mm ammo in a rifle specifically chambered for the 223 Remington. Although the stopping power of .22-caliber bullets remains controversial the 5.56X45mm has served well in now multiple generations of M16 rifles. — Craig Boddington
