|Country of Origin||UK (L16)|
|Date Of Introduction||1987|
|Caliber||3.2 in (81 mm)|
|Weight||121 lb (55 kg) (including basic issue items)|
|Range||91 - 6,133 yd (83 - 5,608 m)|
|Rate of Fire||Maximum: 30 rounds per minute for 2 minutes.|
Sustained: 15 rounds per minute, indefinitely
|Unit Replacement Cost||$24,717|
|Weight||35 lb (16 kg), with blast attenuator device|
|Weight||27 lb (12 kg)|
|Traverse (approximate)||100 mils (10 turns) right or left from center|
|Elevation (approximate)||800 to 1515 mils (10 mils for each turn of elevation drum)|
|Weight||29 lb (13 kg)|
|Weight||2.5 lb (1.1 kg)|
|Length||4.375 in (111 mm)|
|Width||4.75 in (121 mm)|
|Height||7.375 in (187 mm)|
|Field of View||17° (302 mils)|
|Magnification||1.5 unity power|
|Light Source||Self-contained, radioactive tritium gas (H3)|
The M252 81mm mortar is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon.
The components of the mortar consist of a cannon, mount, and baseplate.
The M252 medium mortar offers a compromise between the light and heavy mortars.
Its range and explosive power is greater than the M224, yet it is still light enough to be man-packed over long distances.
The M252 weighs about 93 pounds and can be broken down into several smaller loads for easier carrying.
Rounds for this mortar weigh about 15 pounds each.
The M252 replaced the M29A1 in U.S. service.
M253 Cannon Assembly
The cannon assembly consists of the barrel that is sealed at the lower end with a removable breech plug, which houses a removable
firing pin. At the muzzle end is a cone-shaped blast attenuator device (BAD) that is fitted to reduce noise. The BAD is removed only
by qualified maintenance personnel.
The M177 mount consists of elevating and traversing mechanisms and a bipod.
- The bipod provides front support for the barrel and carries the gears necessary to lay the mortar. The barrel clamp,
which consists of an upper and lower clamp, is situated at the top. The upper clamp is fitted with a locking arrangement that
consists of a curved handle and a spring-loaded locking rod, which is ball-shaped at its lower end. The lower clamp is shaped and
bored on each side to house the buffer cylinders. On its right side, the clamp is recessed to receive the ball end of the locking rod.
A safety latch located at the side of the recess is used to secure the ball.
- The sight bracket is attached to the buffer carrier, which is fitted to the traversing screw assembly. Attached to the
right of the screw is the traversing handwheel. The traversing screw assembly is fitted to the clamp assembly, which is pivoted in
the center on an arm attached to the elevating leg. Attached to the arm is the cross-leveling mechanism, which is attached to the
clamp assembly at its upper end.
- The elevating shaft is contained in the elevating leg; to the left of the elevating leg is the elevating handwheel. A
plain leg is fitted to a stud on the elevating leg and is secured by a leg-locking handwheel. A spring-loaded locating catch is
behind the elevating gear housing, which locates the plain leg in its supporting position for level ground. A securing strap is
attached to the plain leg for securing the bipod in the folded position. Both legs are fitted with a disk-shaped foot with a spike
beneath to prevent the mount from slipping.
The M3A1 baseplate is of one-piece construction, and supports and aligns the mortar for firing.
During firing, the breech plug on the barrel is sealed and locked to the rotatable socket in the baseplate.
The sightunit is the device on which the gunner sets deflection and elevation to hit targets by using the elevation level vial and the cross-level vial.
After the sight has been set for deflection and elevation, the mortar is elevated or depressed until the elevation bubble on the sight is level.
The mortar is then traversed until a proper sight picture is seen (using the aiming posts as the aiming point) and cross-level bubble is level.
The mortar is laid for deflection and elevation when all bubbles are level. After the ammunition has been prepared, it is ready to be fired.
The two major components are the elbow telescope and sight mount. The elbow telescope has an illuminated cross line.
The sight mount has a dovetail, locking knobs, control knobs, scales, cranks, and locking latch.
The following are authorized (Standard B) cartridges for the M252 81mm mortar:
Click here for more information.
- High explosive: M821, M889, M374-series, and M362.
- Red phosphorus/white phosphorus: M819 and M375-series.
- Illuminating: M853 and M301-series.
- Training practice: M879, M880, M68, and sabot.
The mortar squad consists of five men. Their firing positions and principal duties are as follows:
- The squad leader stands behind the mortar where he can command and control his squad.
In addition to supervising the emplacement, laying, and firing of the mortar, he supervises all other squad activities.
- The gunner stands to the left side of the mortar where he can manipulate the sight, elevating handwheel, and traversing handwheel.
He places firing data on the sight and lays the mortar for deflection and elevation.
He makes large deflection shifts by shifting the bipod assembly and keeps the bubbles level during firing.
- The assistant gunner stands to the right of the mortar, facing the barrel and ready to load.
In addition to loading, he swabs the bore after 10 rounds have been fired or after each fire mission.
He may assist the gunner in shifting the mortar when the gunner is making large deflection changes.
- The first ammunition bearer stands to the right rear of the mortar.
He has the duty of preparing the ammunition and passing it to the assistant gunner. He is also the squad driver.
- The second ammunition bearer stands to the right rear of the mortar behind the ammunition bearer.
He maintains the ammunition for firing and provides local security for the mortar position.
He performs other duties as the squad leader directs.
More M252 Art
M252 Photos - Click on image sample to see full size image.
10th Mountain Division's 1st Battalion, 87th Infantry Regiment
U.S. Army Photo by SPC Timothy J. Belt
1024x880, 260K, JPEG
81mm mortar platoon, Battalion Landing Team 1st Bn., 2nd Marines, 22nd MEU
Forward Operating Base Hit, Al Anbar province, Iraq
Marine Corps Photo by Sgt. Richard D. Stephens
1024x1300, 250K, JPEG