General Dynamics Armament and Technical Products produces the MK19 MOD 3 air-cooled system, a blow-back operated, belt-fed, crewserved 40mm grenade machine gun. Highly portable within small soldier units, the weapon's high lethality and broad versatility make it the prime choice of the U.S. Armed Forces as an essential weapon in both offensive and defensive operations 
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Firing M430 High Explosive Dual Purpose grenades, the MK19 provides lethal fire against a variety of targets, including lightly armored vehicles and dismounted infantry. It will penetrate 75mm rolled homogenous armor at a maximum range of 2,050 meters. Dismounted personnel, within a radius of 15 meters from impact, will be immobilized by blast and fragmentation. Features include:

• Sustained automatic or single-shot firing 
• Dual spade grips for stable control
• Removable barrel
• No headspace or timing adjustments required
• Open-bolt firing eliminates cook-off, enhances cooling between bursts and allows sustained firing at three to five-round bursts
• Simple design for easy maintenance
• Mean rounds between failure exceeds 20,000 rounds

Specifications

Machine Gun Builder: General Dynamics
Length: 43.1 inches
Gun Weight: 72.5 pounds
Caliber: 40mm
Maximum Effective Range: 1,650 yards (1,500 Meters)
Maximum Range: 2,242 yards (2,050 Meters)
Cyclic Rate of Fire: 300-400 Rounds per Minute