Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Tail Pistol No. 48 Mk I (Service)Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Tail Pistols No. 54 Mk I and No. 60 Mk I (Service)
BRITISH EXPLOSIVE ORDNANCE
Part 2 - Chapter 2
Pistols

Tail Pistol No. 53 and No. 53A (Service)
Data
Bombs used in G.P. 250- and 500-lb. Mks I, II, and IV, 1,000-, 1,900-, and 4,000-lb.; all M.C. bombs; S.A.P. 250- and 500-lb. Mk V; A.P. 2,000-lb. Mks I, II, and III. The dimensions of this pistol are iden-tical to those of the Pistols No. 28 and No. 30, and so could be used in any bombs in which the latter are used.
Action Chemical long delay of ½ or 1 hour
Armed condition Assumed armed if dropped; armed if arming fork is threaded down to bottom of its cavity in pistol
Fuzes used with None
Arming time Eight arming-fork revolutions, or if dropped from sufficient height to brak ampoule
Body diameter 2 in.
Over-all length 4.25 in.
Color Body brass; V-shaped notch around body painted white

Description: This pistol is similar in appearance to the No. 37 Mk IV, except that the notch around the knurled exterior is painted white, and there is no anti-withdrawal devi-ce incorporated internally, the fuse differs from the No. 37 Mk IV in that a modified stri-ker assembly is used to enable shorter delays to be obtained. The striker is retained by a row of balls around its head. The balls retain the striker by their contact with a chamfe-red thrust sleeve, which, in turn, is located by a celluloid disc. The pistol is fitted with a device, similar to that incorporated in the No. 37 Mk V, consisting of a blotting-paper ring fixed to the base of the pistol head. The arming screw is provided with three slots along a portion of its screwed length. If an ampoule breaks, the tinted acetone passes through these slots into the head of the pistol and stains the blotting paper.

Operation: These pistols are issued assembled for use. When a bomb is fuzed with this pistol, the press cap and safety plate are removed, and the arming screw engaged by the arming fork of the tail arming assembly. The standard arming vanes on the tail unit will be replaced by the special red-colored vanes packed in the pistol box.

When the bomb is released from the carrier, the arming screw of the pistol is screwed down by the rotation of the arming vane of the tail unit, and crushes the ampoule, thus releasing the acetone. The forward movement of the arming screw then continues, and the head of the screw compresses the soft rubber washer, sealing the acetone in the pistol. The solvent action of the acetone softens the celluloid disc so that the thrust sleeve is allowed to move upward, forced by the camming force of the retaining balls against its chamfered edges. The balls are then released, and the striker allowed to ope-rate.

Remarks: The 30-minute delay is obtained with Pistol No. 53, and the one-hour delay with Pistol No. 53A. The alternative delays are provided by varying the strength of the acetone, which is tinted green for the thirty-minute delay and violet for the one-hour delay. The pistols are shipped with the ampoules assembled, and the ampoules are not to be changed. The times of delay quoted are subject to a variation of approximately plus or minus 30%. Should a bomb fuzed with a Pistol No. 53 or No. 53A be dropped from a height of 12 inches or more, the bomb must be considered. It is the practice of the R.A.F. Bomber Command to paint the arming vanes of the tail unit white, but this prac-tice is not general.

Figure 139 - Tail Pistol No. 53

Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Tail Pistol No. 48 Mk I (Service)Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Tail Pistols No. 54 Mk I and No. 60 Mk I (Service)