175mm Self Propelled
Specification from 1963
30 August 1963 TM 9-500
CANNON, 175 MILLIMETER GUN: M113; MOUNT, GUN-HOWITZER: M158;
RAMMER AND LOADER ASSEMBLY ORD NO. 10898300;
MECHANISM, FIRING, CANNON: M35
Model Line item No. Federal stock No.
Cannon Mount Mechanism
M113 (T256E3) 1025-735-4329
CANNON, 175 MILLIMETER GUN: M113 (T256E3) with MOUNT, GUN-HOWITZER: M158, RAMMER AND LOADER ASSEMBLY ORD No. 10898300, AND MECHANISM, FIRING, CANNON: M35, provides the armament for GUN, FIELD ARTILLERY, SELF-PROPELLED: 175-mm, M107 (T235E1).*
The cannon M113 consists of a tube assembly screwed into an internal thread In a breech ring and locked in place by a key and a screw. The tube assembly is of monobloc (one-piece) construction. The chamber and bore are chrome-plated. Longitudinal rails secured to three hoops shrunk onto the jacket maintain the alignment of the cannon In the mount. The breech consists of an outer breech ring containing internal threads into which the tube is threaded.
The gun-howitzer mount M158 includes the recoil mechanism of the hydropneumatic variable recoil type, which controls the forces created by firing and checks the movement of the recoiling parts gradually, to avoid displacement of the vehicle, and also returns the recoiling parts into their original position. The major components are the recoil, counterrecoil, and recuperator cylinders, contained In the gun cradle, and the replenisher cylinder.
The rammer and loader assembly operates to lift a projectile from the rear or left side of the vehicle, position it for ramming, and ram it into the cannon chamber. Hydraulic power for operation is obtained from the vehicle hydraulic system. Operation can also be accomplished manually by means of hand cranks.
The firing mechanism is a percussion type and is operated manually by a lanyard.
Differences among models
Data plate location
Standard A (OTCM 37597)
Cannon complete 13,800 lb
Barrel assembly 12,050 lb
Breech mechanism 1,750 lb
Tipping parts 18,300 lb
Tube 413 in.
Cannon 35 ft, 8 in.
Length 349.16 in.
Number of grooves 48
In calibers 60
Breechblock Welin-step thread
Operation manual, by lanyard
Weight 4,500 lb
Weight (approx) 3,925 lb
Number of recoil cylinders 1
Length of recoil:
Normal high elevation-28 to 30 in.
Maximum low elevation-68 to 70 in.
Type of recoil oil FSN 9150-255-4443 (OHC)
Oil capacity 15 gal
Replenisher 2 pt
Recuperator 2 pt
Elevation (max) 65 deg
Depression 0 deg
Turret traverse (right or left) 30 deg
Traversing and elevating operation manual or hydraulic
Muzzle velocity 3000 fps
Range (maximum) 32,800 meters
Allowable recoil (variable)
Rate of fire:
Normal 1 rd per 2 min
Maximum 1 rd per 1 min
Maximum number of rounds fired consecutively at max rate
Maximum powder pressure permitted 50,000 psi
Average accuracy life 400 rd (EFC)
Sighting and Fire control:**
Installed on self-propelled gun M107 prior to issue:
MOUNT, TELESCOPE: direct fire, M138
MOUNT, TELESCOPE: panoramic, M137 (T186E3)
Boxed and stowed on self-propelled gun M107 prior to issue:
FUZE SETTER: M26 and M27
LIGHT INSTRUMENT: M52
PERISCOPE, TANK: M17
POST, AIMING: M1A2
QUADRANT, FIRE CONTROL: elevation, M15 (T23E2)
QUADRANT, FIRE CONTROL: gunner's, M1A1
REFLECTOR, AIMING POST: clear, M1
REFLECTOR, AIMING POST: red, M2
SCALE. GRAPHICAL FIRING:
SCALE, GRAPHICAL FIRING: site
TELESCOPE, ELBOW: direct fire, M116C
TELESCOPE, PANORAMIC: M115 (T146)
Basic Issue Item: See TM 9-2300-216-10
PROJECTILE, 175 MILLIMETER, DUMMY:
CHARGE, PROPELLING, 175 MILLIMETER, DUMMY:
PRIMER, PERCUSS10N INERT:
References: TM 9-2300-216-10, TM 9-1000-218—35, TM 9-1000-218-35P
*For characteristics and data, see item in section 23.
**For characteristics and data, see Item in sections 12, 14, 18, and 27.
Thanks to Lynden T. Couvillion (Couvi) for sending in the data.
Thanks to Charles E. Stephenson for preparing the information.