M18 recoilless rifle

M18 recoilless rifle

M18 recoilless rifle standing on its bipod and monopod, and dummy rounds (note perforated cartridge cases)

 

M18 recoilless rifle

M18 recoilless riflewith its bipod folded to form shoulder support

 

M18 recoilless rifle

Firing the M18 recoilless rifle

 

M18 recoilless rifle

Loading the M18 recoilless rifle

 

 

Caliber

57 mm / 2,25”

Type

Recoilless weapon

Overall length

1560mm

Weight

20,1 kg empty

Max. effective range

~400 meters

Armor penetration

~75mm / 90o

 

The M18 recoilless rifle was developed in USA between 1943 and late 1944 as a man-portable anti-tank weapon for infantry. Initially known as T15, it was officially adopted as M18 in late 1944, and first weapons reached frontline units by early 1945. M18 recoilless rifles were widely employed by US forces in Korea, more often against enemy entrenchments, machine gun nests and light buildings than against tanks, because penetration of the HEAT round was usually insufficient to defeat  frontal armor of Soviet-made T34 tanks. Compared to contemporary M1 and M9 Bazooka anti-tank launchers, M18 recoilless rifle was noticeably more accurate and had much longer range (max range was listed as about 4900 yards / 4460 meters), thanks to its rifled barrel and higher muzzle velocity. On the other hand, the rifle itself and its ammunition were significantly heavier and more expensive than Bazookas.

Over the time, M18 recoilless rifles were used by armed forces of the Austria, Brazil, China, France, Greece, Italy, Japan, south Korea and a host of other nations.

 

The M18  recoilless rifle uses following main types of ammunition – M306 / M306A1 HE rounds, M307 / M307A1 HEAT rounds, M308 / M308A1 WP (smoke / incendiary) rounds, T25E4 canister / antipersonnel rounds as well as target practice rounds with inert warheads. The complete round of ammunition is assembled using steel, rimmed case which has 400 perforations in its side walls. Projectiles have pre-engraved driving bands to engage barrel rifling with minimum of friction. Case perforations allow most of the hot propellant gases to escape into the barrel and then rearward, through the venturi nozzle, compensating for the recoil and generating a large and dangerous backblast. Typical round for M18 recoilless rifle weights about 2,5 kg, including about 450 g (1 pound) of propellant stored inside the combustible, water-proof bag inside the case; warhead weight is about 1,25 kg, including 250 g of explosive for HE round and 180 g of explosive for HEAT rounds. Muzzle velocity was listed as 1200 fps / 366 m/s.

M18 recoilless rifle is built around a steel rifled barrel, open at both ends. Rear end of the barrel is fitted with breechblock and venturi nozzle. For loading, breechblock is opened up, round of ammunition inserted into the breech and breechblock is closed. Propellant ignition is achieved by means of the conventional percussion primer at the base of the case. Pistol grip, trigger unit, folding shoulder rest / bipod and telescope sight base are attached to the barrel. Pistol grip is normally located at the angle to the right of the barrel. Gun is to be fired from the shoulder, using shoulder rest and pistol grip, or from the ground, using either integral bipod (which, when folded, forms the shoulder support) or machine gun tripod (M1917A1 or M74). Aiming is achieved by using optical telescope sight, with range settings between 200 and 1800 yards.