Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Nose Pistol No. 27 Mks I, I* and No. 42 Mks I and II (Service)Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Nose Pistol No. 33 Mk I (Service)
Part 2 - Chapter 2

Tail Pistols No. 28 Mks II*, III, and IV, No. 30 Mks III* and IV, and No. 65 Mk I (Service)

Bombs used in No. 28 G.P. 250-lb. Mk IV, 500-lb. Mk IV, 1,000-lb., 1,900-lb. and 4,000-lb.; all M.C. bombs; S.A.P. 250-lb. Mk V, and 500-lb. Mk V; A.P. 2,000 lb. Mk IV; A.S. 100-, 250-, and 500-lb. Mk IV, when used for land bombardement; and L.C. 500-lb. No. 30 - A.S. 100-, 250-, and 500-lb. Mk IV. May also be used in any of above bombs when sensitive-type tail initiation is required
Action Instantaneous on impact
Armed condition When arming fork is less than two rotations from being completely unthreaded from striker stem
Fuzes used with Nose Pistols No. 27, 42, or 44. Tail Pistol No. 28 might be found in A.S. 100-lb. Mk V with Nose Fuze No. 858
Arming time 13 arming fork revolutions (arming fork unthreads completely in 15 revolutions)
Body diameter 2 in.
Over-all length 3 7/8 in.
Color Brass body; No. 30 has green groove around body.

Description: The Pistols No. 28 and No. 30 consist principally of a body with 1.1-in. standard threads, a striker threaded at the top end to take the arming fork, and a creep spring to prevent the striker from hitting the detonator until impact. The creep spring is housed in a creep spring holder, which threads into the bottom of the pistol body. A tab locking device for securing the pistol in the bomb is fitted around the body just below the knurled section, and a washer is fitted just above the body threads. Until placed in the bomb, the arming fork is preventing from rotating by a safety plate resting on two narrow recesses inside the upper part of the body, and extending between the arming fork arms.

When issued, the pistols are covered at the top by a press-cap and overseal. A guide pin, threaded into the side of the lower body extension, engages in one of two grooves in the striker and prevents it from rotating.

The Pistol No. 28 has a 5/8-in. knurled surface around the upper part of the pistol body. The Pistol No. 30 has the same type of knurled surface with a ¼-in. green groove in the center of the knurled portion. The Pistol No. 28 has a blunt striker, while the No. 30 has a needletype striker.

Operation: When the bomb is loaded in the plane, the arming fork of the pistol is en-gaged with the arming fork on the end of the reach rod which extends through the tail unit. When the bomb is released, the arming vanes on the end of the reach rod rotate and thus unthread the arming fork of the pistol until it rises clear of the threaded end of the striker stem. At this point the pistol is armed, and on impact the weight of the striker body is sufficient to overcome the creep spring and force the striker point against the cap in the detonator.

Remarks: The Pistol No. 30, though originally intended primarily for use in the A.S. bombs, is gradually replacing the No. 28 in other types of bombs in which a sensitive-type tail initiation might be required. The No. 30 is now considered the standard British tail pistol.

No. 28 Mk II* is a converted Mk II, which is obsolete, and the Mk III is of new manu-facture. The Mk IV is of similar construction, but the body, safety plate, and creep spring holder are of moulded plastic material. Also in the Mk IV an internal projection in the central bore replaces the guide pin of the earlier marks. Pistols No. 30 Mk III* and Mk IV are similar to the Pistols No. 28 Mk II* and Mk III, except that the striker has a long, sharp point and the knurled section of the body has a green groove around it.

The Pistol No. 65 Mk I resembles the Pistol No. 28 externally, while internally it differs from it by having a sharp, sensitive striker and a different type arming assembly. The arming assembly consists of an arming screw, pinned securely to the arming fork, and screwed into a threaded central hole in the after end of the striker.

Figure 128 - Tail Pistol No. 28 and No. 30

Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Nose Pistol No. 27 Mks I, I* and No. 42 Mks I and II (Service)Part 2 - Pistols, Fuzes, and Detonators; Chapter 2: Nose Pistol No. 33 Mk I (Service)