M240B

M240B

 

M240B

The M240B is a belt-fed, gas-operated, air-cooled, crew-served medium machine gun chambered for the 7.62x51mm NATO cartridge that fires from the open bolt position.

Weights:

  • Gun: 27.1lbs
  • Barrel: 6.6lbs
  • all SL3 components: 12.9lbs
  • Tripod w/ T&E: 14.8lbs

Ranges: 

  • Max Range: 3725m 
  • Max effective (point): 800m
  • Max effective (area): 1800m
  • Grazing Fire: 600m 
  • Trace Burnout: 900m

You can purchase the full publication for Machine Guns and Machine Gunnery using our Amazon-affiliated link below

Machine Guns and Machine Gunnery

Rates of Fire:

  • Sustained: 100rds/min, 6 - 8 round burst, 4 - 5s pause, barrel change every 10mins
  • Rapid: 200rds/min, 6 - 8 or 10 - 12 round burst, 2 - 3s pause, barrel change every 2mins
  • Cyclic: 550-650rds/min, continuous burst, barrel change every 1 min

 2800 feet per second

Rifling: 4 grooves with a uniform right hand twist, one turn in 12 inches

Weapon Conditions: 

  • Condition 4: Bolt forward, chamber empty, no rds on feed tray, cover closed, wpn on “Fire”
  • Condition 3: Bolt forward, chamber empty, rds on feed tray, cover closed, wpn on “Fire”
  • Condition 2: N/A
  • Condition 1: Bolt locked to rear, chamber empty, rds on feed tray, cover closed, wpn on “Safe” 

Immediate Action:

  • Sound off “Misfire” (x3)
  • Wait 5 seconds for a hang fire
  • Pull cocking handle to the rear, observe for feeding and ejecting
  • If you have feeding and ejecting, continue on with mission
  • If you DO NOT or 2nd consecutive misfire, go into PAD’s
  • PADs:
  1. Place the weapon on Safe
  2. Assume live round in Chamber
  3. Determine whether the barrel is hot or cold.
  • Hot barrel for M240B
    • More than 200rds within 2 minutes
    • Long continuous bursts
    • 15mins since last deemed a hot barrel
    • Vehicle Commander or Team Leader deems it hot
  • If hot, wait 15mins for barrel to cool down
  • Once cold, unload and clear weapon, go into CCLI
    • Clean
    • Care
    • Lubricate 
    • Inspect

Cycle of Operations:

  1. Feeding
  2. Chambering
  3. Locking
  4. Firing
  5. Unlocking
  6. Extraction
  7. Ejecting
  8. Cocking

Major Component Diagram:

(US Department of the Army. (2017.) Medium Machine Gun (TC 3-22.240))

Significance: 

The M240B's robustness, firepower, and versatility make it a critical asset in the infantry's arsenal. Its reliability in adverse conditions, coupled with its capability for sustained fire, contributes significantly to the firepower and effectiveness of military units on the ground.

 For information, check out our guide on Basic Machine Gun Gunnery. Click the link below

BASIC MACHINE GUN GUNNERY

***Disclaimer: This is not advice or an instructional. We do not represent the DOD.***

***Purely for Educational Purposes only.***

You can purchase the full publication for Machine Guns and Machine Gunnery using our Amazon-affiliated link below

Machine Guns and Machine Gunnery

 You can also download the PDF here for free 

MCWP 3-15.1 Machine Guns and Machine Gun Gunnery 

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