MOUNTING, TRIPOD, ·303-in. MAXIM GUN, MARK IV.
The mounting consists of a crosshead (a), elevating gear (b), and socket (c), mounted on three legs.
It is constructed to give 13 degrees elevation and 25 degrees depression at heights varying from 14½-in. to 30-in. from the axis of the gun to the ground. By arranging the position of the rear and front legs respectively, elevation may be given up to about 43 degrees and depression to 55 degrees. An all-round traverse can be obtained.
The crosshead (a), to which the gun is pivoted, is formed with a pivot to fit into the socket (c) and an arm (d) which carries the elevating gear (b).
The elevating gear, which is actuated by a hand wheel (v), consists of an inner and outer screw (right and left-handed) and a nut working within a tumbler (g). The tumbler is split and provided with a jamming bolt (h), by which the wear may be taken up. The inner part of the screw is attached to the crosshead by a chain. Chains also, for future manufacture and replacement, will secure the joint pins to the mounting.
The socket (c) is bored to receive the crosshead and is provided with three lugs (n), to which the legs are hinged; a jamming block and screw with handle (f) is attached to the front to secure the crosshead in any desired angle of traverse; the block works in a recess in the upper portion of the crosshead and prevents it from rising. Both faces of the rear lug and one face of each front lug are fitted with clutch plates having radial serrations to correspond with similar serrations on the faces of the leg joints. Joint studs with disc spring and jamming handle (s) are
Plate III.
MOUNTING TRIPOD ·303 INCH, MAXIM GUN MARK.
SCALE = ⅛
SIDE ELEVATION.
A Crosshead B Elevating gear C Socket D Arm, crosshead F Screw, clamp checking traverse G Tumbler, elevating gear H Bolt, jamming elevating gear J Front legs K Rear leg M Shoes N Socket lugs S Stud, joints, a jamming handle, front legs T Joint pin, a jamming handle rear leg V Handwheel elevating gear
fixed to the front lugs, by which the legs are securely clamped to the socket in the required position.
The legs (j, k) are of tubular steel, the lower ends being fitted with shoes (m) to steady the mounting on the ground, and the upper ends having a joint with radial serrations mentioned above. The rear leg is provided with a joint pin with nut and jamming handle (t).
On a portion of the periphery of the leg joints, numbers are stamped at regular intervals so that when read in conjunction with a zero mark the relative position of the legs to their normal position may be readily seen.
A strap is fixed to the rear leg to secure the three legs during transport.
When firing, the ammunition box is placed on the ground on the right side of the gun.
Weight of mounting 48 lbs. variable.