Rifle, Anti-Tank, .55 in, Boys

Boys Anti-tank Rifle
Boys anti-tank rifle Mk I
Type	Anti-tank rifle
Place of origin	United Kingdom
Service history
In service	1937–1943
Used by	See Users
Wars	World War II, Winter War
Production history
Designed	1937
Manufacturer	Royal Small Arms Factory
Produced	1937–1940
No. built	~62,000
Variants	Mk I, Mk II
Specifications
Weight	35 lb (16 kg) unloaded
Length	5 ft 2 in (1.575 m)
Barrel length	36 in. (910 mm); Airborne: 30 in. (762 mm)
Cartridge	Kynoch & RG .55 Boys
Calibre	(bullet diameter).5625 in. (14.3 mm) (9/16 in.) In
Action	Bolt
Rate of fire	~10 round/min
Muzzle velocity	Mk I: 747 m/s (2,450.1 ft/s) Mk II: 884 m/s (2,899.5 ft/s)
Effective firing range	23.2mm penetration at 90° 100 yards (91 m) 18.8mm penetration at 90° 500 yards (460 m)
Feed system	5-round detachable box magazine

Mk I: 747 m/s (2,450.1 ft/s)

23.2mm penetration at 90° 100 yards (91 m)

The Rifle, Anti-Tank, .55in, Boys commonly known as the "Boys Anti-tank Rifle" (or incorrectly "Boyes"), was a British anti-tank rifle in use during the Second World War. It was often nicknamed the "elephant gun" by its users due to its size and large bore.

There were three main versions of the Boys, an early model (Mark I) which had a circular muzzle brake and T-shaped monopod, built primarily at BSA in England, a later model (Mk I*) built primarily at the John Inglis and Company in Toronto, Ontario, Canada, that had a square muzzle brake and a V shaped bipod, and a third model made for airborne forces with a 30-inch (762 mm) barrel and no muzzle brake. There were also different cartridges, with a later version offering better penetration.

Although adequate against light tanks and tankettes in the early part of the war, the Boys was ineffective against heavier armour and was phased out in favour of the PIAT mid-war.

The eponymous creator of this firearm was Captain H. C Boys (the Assistant Superintendent of Design) who was a member of the British Small Arms Committee and a designer at the Royal Small Arms Factory, Enfield. It was initially called Stanchion but was renamed after Captain Boys as a mark of respect when he died a few days before the rifle was approved for service in November 1937.

A bolt action rifle fed from a five-shot magazine, the weapon was large and heavy with a bipod at the front and a separate grip below the padded . In order to combat the recoil caused by the large 0.55 inch (13.9 mm) round, the barrel was mounted on a slide, and a shock absorber was fitted to the bipod along with a muzzle brake on the barrel. The Boys had been designed with numerous small narrow-slotted screws of soft steel set very tight into the body of the weapon and its repair and maintenance proved a nightmare for British ordnance repair crews.