United States' flag

United States' T48 Gun Motor Carriage

Photos

T48 57 mm Gun Motor Carriage:
United States' T48 57 mm Gun Motor Carriage
Aberdeen Tank Museum
     

Design

It was ordered to be developed by the Ordnance Committee in April 1942. It was only to be temporary until a more powerful design could be developed.

Originally designed for US and British service but none saw service with US forces.1 Production for Britain was initiated on October 18, 1942.

Placed on an M3 half-track. The gun was mounted in the center of the vehicle behind the front bulkhead. A gunner's seat pivoted independently of the main gun.

  Weight Muzzle Velocity
HE 6.25 lb1 2,720'/sec1
AP   2,700'/sec1

M1 gun could penetrate 55 mm armor at 1,000 yards. Muzzle velocity of 2,800 ft/sec. Gun was positioned between the 2 windshields and placed in a quick release traveling lock.

Prototype

Production

  • T48:
    • Production: 1942
    • Manufacturer: Diamond T, Autocar1

Variants

Usage

British Service

Was equipped with British Wireless Set, No. 19.

Russian Service

Re-armed with more powerful Russian 57 mm anti-tank gun.

Specifications

  T48 Gun Motor Carriage
Crew Commander, driver, gun crew (3)
51
Physical Characteristics  
Weight 19,000 lb, 21,000 lb1
Length w/gun 20' 3.5"1, 21' 5/8"
Length w/o gun  
Height 7', 8' (approximate)1
Width 7' 1"1
Width over tracks  
Ground clearance 11 3/16"1
Ground contact length 3' 10.75"1
Ground pressure 12.3 psi1
Turret ring diameter  
Armament  
Main 57 mm M1 gun1
Secondary  
MG  
Side arms 5: .30 cal Rifles (British)
Grenades
Quantity  
Main 501, 99
Secondary  
MG  
Side arms Grenades: 22
Armor Thickness (mm)  
Hull Front, Upper 0.5"@0°1, 6
Hull Front, Lower 6
Hull Sides, Upper 0.25"@0°1, 6
Hull Sides, Lower 6
Hull Rear 0.25"@0°1, 6
Hull Top 6
Hull Bottom 6
Turret Front  
Turret Sides  
Turret Rear  
Turret Top  
Engine (Make / Model) While 160 AX1
Bore / stroke  
Cooling Water1
Cylinders I-61
Capacity  
Net HP 1471
Power to weight ratio  
Compression ratio  
Transmission (Type) Dual range synchromesh1
8 forward, 2 reverse1
Steering Cam and twin lever1
Steering ratio  
Starter  
Electrical system  
Ignition  
Fuel (Type) Gasoline1
Octane  
Quantity 60 gallons1
Road consumption 3.6 mpg1
Cross country consumption  
Performance  
Traverse 27.5° both ways
Speed - Road 45 mph1
Speed - Cross Country  
Range - Road 200 miles, 220 miles1
Range - Cross Country  
Turning radius 30'1
Elevation limits -5° to +15°
Fording depth 2' 8"1
Trench crossing  
Vertical obstacle 1'1
Climbing ability 30° slope1
Suspension (Type) Front: Semielliptic spring1
Rear: Vertical volute spring1
Wheels each side Front: 11
Rear: 2 sets of articulated four-wheeled bogies1
Return rollers each side 11
Tracks (Type) Endless band1
Length  
Width 12"1
Diameter  
Number of links  
Pitch 4"1
Tire tread  
Tire size 8.25 x 201
Track centers/tread 63 3/16"1
Wheel centers 64.5"1
Wheel base 135.5"1

Sources:

  1. Tank Data 2, Aberdeen Proving Grounds Series, E. J. Hoffschmidt and W. H. Tantum IV, 1969