Initiating devices for British bombs are divided into two distinct groups, pistol and fuzes. The term PISTOL is used to decribe an initiating device which contains no explo-sive components (primer, detonator, or booster) as it is normally shipped or issued. A PISTOL is purely a mechanical device for initiating explosive components which are inser-ted in the bomb as a separate entity. Initiating devices which contain explosive compo-nents as integral parts, however, are termed FUZES. Generally, in addition to a primer-detonator combination, FUZES also are fitted with burster charges or boosters.

As a general rule, British pistols are used to initiate high explosive bombs, while British fuzes are employed in miscellaneous types of missiles, such as smoke bombs, flares, etc. Many exceptions, however, will be found to this rule.

In most instances, fuzes and pistols are designed so that they may be dropped "SAFE" by leaving some form of safety device (safety fork, safety pin, or safety clip) in plase. Certain fuzes and pistols, however, may not be dropped "SAFE", due to the absence of safety devices or to the automatic removal of such devices when the bomb is released.

In bombs of 500 lb. and under in weight, fuzes cannot be used, and pistols are scre-wed directly into an exploder container, which contains booster pellets and a detonator. In bombs over 500 lbs., the pistol is screwed into a detonator holder, which in turn is threaded into the exploder container of the bomb. In this size bomb, if a fuze is to be used, the detonator holder is omitted, and the fuze is screwed directly into the exploder container. A discussion of the detonators used with British pistols will be found in Appen-dix I. Suffice it to say here that relatively insensitive anvil-type detonators are emplyed with pistols which have blunt strikers. Sensitive "capsule" detonators are used with pistols containing needle-pointed strikers. The following diagram shown the typical fuzing arrangment for a bomb of more than 500 lbs. in weight

Tail fuzes normally have arming vanes as an integral part of the fuze mechanism. Tail pistols, on the other hand, generally are armed by an arming fork, which engages a simi-lar fork on the reach rod attached to the arming vanes incorporated as an integral part of the standard British tail unit.

A novol type of device is employed by the British to secure their pistols in bombs. This device consists of a spring clip or "tab locking device" fitting around the base of the pis-tol. The clip has a series of dents which fit into cavities located around the pisotl body. A small tab, about ¼" long, projects below the clip, and when the pistol is screwed into the bomb, the tab engages one of the small holes drilled in the top of the exploder con-tainer. This prevents the clip from moving around with the pistol and provides a ratchet effect. This device prevents the pistol from working loose while in the plane and yet lea-ves the pistol only hand tight in the bomb, so that it may be easily removed.

Most British bombs are equipped for both nose and tail fuzing, and occasionally dual fuzing is used. However, it is the more common practice for British armorers to fuze either nose or tail, using only one fuze. Generally, if a delay is desired, the bomb is fuzed in the tail, while nose pistols or fuzes will be used for instantaneous action.

Included in this publication are all British pistols and fuzes currently in service use. In addition, obsolescent pistols and fuzes, which are no longer in manufacture but stocks of which are still available for use, are also presented. Certain pistols and fuzes have been declared obsolete by the British, but because of their former importance or as a matter of interest have been included in the book. More important obsolete items, such as the No. 845 fuze, are presented in the main body of this section. Other obsolete items are included in chart form at the end of the section.

British fuzes and pistols are designated by a number and a mark, the number corres-ponding to the U.S. "Mark" designation, the Mark (always expressed in Roman numerals) equivalent to the U.S. "mod". Since some British pistols carry the same number and mark designations as a British fuze, the name "Pistol" or "Fuze" must always follow the number and mark designation, as: No. 38 Mk. I Pistol, No. 38 Mk. I Fuze, etc.

lthough the fuze or pistol designation is almost invariably stamped on the external sur-face of the fuze or pistol, in many cases this designation is not visible when the fuze or pistol is inserted in the bomb. Since some British fuzes and pistols contain anti-with-drawal devices and others are inherently dangerous to remove, it becomes necessary to recognize fuzes and pistols from their external appearance alone. To assist recognition the following section has been included in this publication. In all cases, the fuzes and pistols are shown in the armed position, and only so much of the fuze or pistol which re-mains visible when inserted in the bomb is pictured. Reference numbers indicate the pages in this publication where diagram sketches and complete descriptions of the item in question may be found.