Developed in 1915 to replace the earlier 6 inch 30 cwt model, it co-existed with the 6 inch 26 cwt Howitzer, hence the reason for including the weight in the nomenclature. Although replaced by the 4.5 and 5.5 inch guns, after 1942 it remained in use in the Far East until the end of the war. The design was so sound there was only ever a Mark 1, the only change being to upgrade the wooden wheels of the 6 inch 26 cwt Howitzer to pneumatic tyres.
Data
| Weight of gun & breech mechanism | 2,856 lbs |
| Total Length | 87.55 inches |
| Length of Bore | 79.8 inches (13.3 calibres) |
| Rifling | 36 grooves uniform Right Hand 1/15 |
| Breech Mechanism | Asbury interrupted screw, percussion fired |
| Elevation | 0° to +45° |
| Traverse | 4° Right & Left |
| Recoil System | Hydropneumatic, variable, 24 to 54 inches |
| Weight in Action | 9,262 lbs |
Carriage
| Mark 1R | Wooden wheels, rubber tyres |
| Mark 1P | Pneumatic tyres |
Performance
| Firing standard 86 lb High Explosive Shell | |
| Muzzle velocity | 1,409 ft/sec |
| Maximum range | 11,400 yards |
Ammunition
| Shell High Explosive Streamlined 86 lb Mark 1D | Filled with Amatol or Lyddite |
| Shell High Explosive Streamlined 100 lb Mark 1D | Similar to previous but 3 inches longer |
| Propelling Charge | |
| Super charge for use with 86 lb shell | Weight 5 lb 3 oz divided into 5 charges |
| Normal charge for use with 100 lb shell | Weight 4 lb 11 oz divided into 5 charges |