The “Recoilless Gun” is a short rifled howitzer containing a tube of monobloc steel construction, a breech ring, breech mechanism and block, and a venturi tube. Intended for airborne operations, the weight of the L.G. 40 has been kept to a minimum by the use of hollow machine parts, plastic washers, tubular platform, and aluminum alloy body. It is used for antitank and antipersonnel purposes.
Interrupted collars on the breech end of the tube are used to attach it to the breech rings. The tube is also machined to seat the extractor and the barrel lock. The breech, which is of the horizontal sliding block type, is operated by a lever. This lever, when depressed, also cocks the piece.
The gun has no recoil or counterrecoil system. A funneled tube (venturi) attached to the rear of the bored breechblock allows the gases to escape to the rear, thus eliminating recoil.
The sighting equipment consists of a base bracket, oscillating bracket, cross-leveling gear, range gear, telescope carrier, and telescopes.
The carriage has a circular base to which three tripod legs are pivoted in lugs. The wheels, which can be detached for transport, are light-weight metal disks fitted with solid rubber tires.
The gun can be traversed 360° by locking the elevating mechanisms, but its ordinary traverse is 60°. Elevation is limited to 42° by stops, but the rack can be locked at 20°.
SPECIFICATIONS
| Caliber | 7.5 cm (2.95 ins.) | |
| Length of tube | ||
| Weight (travelling position) | 325 lb. | |
| Weight (firing position) | 321 lb. | |
| Length (travelling position) | 45 ins. | |
| Length (firing position) | ||
| Height (travelling position) | ||
| Height (firing position) | ||
| Width (overall) | ||
| Width of trail spread | ||
| Length of bore | 17.5 ins. | |
| No. of grooves | 28 | |
| Width of grooves | .2 in. | |
| Depth of grooves | .03 in. | |
| Width of lands | ||
| Muzzle velocity (H.E. shell) | 1,197 f.s. | |
| Max. range (horizontal) | 7,400 yds. | |
| Max. range (vertical) | ||
| Rate of fire | ||
| Traverse | 30° x 2—360° | |
| Elevation | -15 +42° | |
| Depression | -15° | |
| Length of recoil | ||
| Ammunition | 3 types | |
| Wt. of projectile | H.E. 12 lb., 9 oz.; A.P.C.B.C. 15 lb.; hollow charge 10 lb., 2 oz. |
German: p. 119