Operation M1919 Browning machine gun

us soldiers fire m1919a4 in aachen


loading

the m1919 fired .30 cal m1906 (30-06) ball cartridge, , later .30 caliber m2 ball cartridge, contained in woven cloth belt, feeding left right. metal m1 link later adopted, forming disintegrating belt.

two marines m1919a4 on namur island during world war ii

loading accomplished inserting pull tab on ammunition belt left side of gun - either metal links or metal tab on cloth belts - until belt-holding pawl @ entrance of feed way grabbed belt , held in place. cocking handle pulled palm of hand facing up, , released. advanced first round of belt in front of bolt extractor/ejector on bolt grab first cartridge. cocking handle pulled , released second time. removed first cartridge belt, advanced next round position grabbed , moved first round down chamber of barrel ready firing.

as bolt went battery, extractor grabbed next round on belt advanced , resting in feedway waiting loaded. every time gun fired single shot, gun performed sequence of extracting , ejecting spent round bolt came rearward, loading next round fired barrel, advancing belt, grabbing next round in preparation loading, chambering bolt came forward again under tension spring. if trigger held down, gun continue fire in full automatic, repeating sequence on , on until stopped.

the gun s original design water-cooled machine gun (see m1917 browning machine gun). when decided try lighten gun , make air-cooled, design gun fires closed bolt created potentially dangerous situation. if gun hot prolonged firing, cartridge ready fired resting in red hot barrel, causing propellant in cartridge heat point ignite on own without warning. each further shot heating barrel more happened, gun continue fire , become uncontrollable until ammunition ran out, since trigger not causing gun fire in situation. known cook-off, , reason gunners taught cock gun palm facing up, in event of cook-off, thumb wouldn t dislocated reciprocating charge handle. gunners trained manage barrel heat firing in controlled bursts of 3 5 rounds, delay between bursts delay heating. other machine gun designs fired in same way, though feature quick change barrels , fire open bolt, 2 features make air-cooled machine guns capable of sustained fire, , features m1919 design lacked.

firing

when gun ready fire, round in chamber , bolt , barrel group locked together, locking block @ rear of bolt. when rear of trigger pivoted upwards operator, front of trigger tipped downward, pulling sear out of engagement spring-loaded firing pin, allowing move forward , strike primer of cartridge.

as assembly of bolt, barrel , barrel extension recoiled rear of gun upon firing, locking block drawn out of engagement cam in bottom of gun s receiver. recoiling barrel extension struck accelerator assembly, half-moon shaped spring-loaded piece of metal pivoting receiver below bolt , behind barrel extension. tips of accelerator s 2 curving fingers engaged bottom of bolt , caused move rapidly rear. extractor-ejector mechanism pivoted on front of bolt, claw gripped base of next round in belt. camming track in left side of receiver caused move down bolt moved back, lowering next round down on top of fired case, pushing straight down out of extraction grooves of bolt face through ejection port. spring in feed tray cover pushed extractor-ejector down onto next round, if feed tray cover opened, extractor-ejector pulled upwards if belt needed removed.

the belt feed lever connected belt feeding pawl @ front end, had cam pin @ rear end ran through track in top of bolt, , pin in feed tray cover acted pivot between 2 ends. rearward movement of bolt caused rear end of feed lever pull right, causing feeding pawl @ other end move left on belt. pawl pull belt further right bolt came forward again, sending loose m1 link of previous round taken out of belt fly out right side of receiver. recoil buffer tube extended of receiver make cycle of bolt smoother previous designs, absorb of recoil of bolt, , formed place pistol grip installed.

except m1919a6, other variants had mounted on tripod or other type of mount used effectively. tripod used infantry allowed traverse , elevation. aim gun along vertical axis, adjustment screw needed operated. allowed gun pointed upwards or downwards, free traverse either side. gun aimed using iron sights, small folding post @ front end of receiver , rear aperture sight on sliding leaf range graduations 200 1,800 meters in 200 meter increments. when folded down, aperture formed notch used fire gun without flipping leaf. rear sight had windage adjustment dial on right side.