.55 inch Boys Proof & Tracer

Proof

There were three marks of .55 inch Boys proof cartridge, each designed to give approximately 25% higher pressure than the corresponding Ball round.The first was "Cartridge S.A. Proof .55 inch Q Mark I" and was not shown in List of Changes. It was to Design DD/L/7916 dated December 1936. It utilised a standard brass case copper washed or "Reddened" all over. The bullet was the lead cored 930 grain Ball Mark I bullet and the propellant charge was 220 grains of Cordite MDT 7-2. No examples are known, but the headstamp should include the code "Q I" and have a yellow primer annulus.The "Cartridge S.A. Proof .55 inch Q Mark II" , like the Mark I, was not shown in List of Changes but since it reflects the introduction of the Ball Mark II round probably dates from the same time, January 1940. It used the same copper washed brass case but was fitted with the 930 grain steel cored Ball Mark II bullet. The charge was 215 grains of Cordite MDT 7-2. The headstamp included the code "Q II" and the primer annulus was yellow.The "Cartridge S.A. Proof .55 inch Q Mark IIIz" was unique among the .55 inch Boys cartridges in that it had a nitrocellulose charge rather than Cordite. It reflected the introduction of the Ball Mark III round and utilised the steel cored 735 grain bullet from that round. The charge was 198 grains of nitro-cellulose. In other respects it was similar to the earlier marks and included "QIIIZ" in the headstamp.

Illustrated are (left) are Proof Q Mark II headstamped "K41 QII" and (right) Proof Q Mark IIIz headstamped "K42 QIIIZ".

Tracer

The .55 inch Boys Tracer G Mark I is something of an enigma, since it was only provisionally approved and soon faded from the scene.Trials were conducted at Woolwich in mid 1938 with rounds supplied by ICI Kynoch to design DD/L/8549 and the round received provisional approval in November that year but was not shown in List of Changes. Like other experimental .55 inch Boys cartridges these tracer rounds used the headstamp of the .5 inch Stanchion round with the Design number "7246" and overstamped with a "G" for tracer.The specification called for a trace to 800 yards with a match to the trajectory of the armour piercing rounds to 600 yards. The bullet was flat based with a lead/antimony sleeve containing the copper tracer canister and an aluminium tip filler and weighed 930 grains. The tracer compound was 23 grains of Kynoch F4 composition with 12 grains of SFG priming.It was obviously intended that there should be a Practice Tracer as well since Kynoch production in 1937 included the code "P.G.I" in the headstamp with the "P" struck out. It had a red primer annulus.Since by then the Boys rifle could only be effective at close range interest in a tracer round quickly diminished and it is doubtful if much was ever issued.Illustrated (left) Tracer G Mark I and (right) the headstamp K.37 P.G.1"