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Boys 0.55in

United Kingdom (1937)
Picture of Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR)
Picture of Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR) Picture of Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR)
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The Boys Anti-Tank rifle proved to be of some value for the British Army, particularly against earlier light and medium tank designs of the World War 2.

Detailing the development and operational history of the Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR).  Entry last updated on 6/11/2018; Authored by JR Potts, AUS 173d AB and Dan Alex; Content ©

Recognizing the increased reliance on armor by the world's armies in the lead-up to World War 2 (1939-1945), the British Army issued a requirement in 1934 for a portable, "light" anti-tank weapon based around the concept of an oversized rifle firing a massive, armor-penetrating bullet. The German Army of World War 1 (1914-1918) attempted such a feat to combat the arrival of British and French tanks but the design proved lacking on the whole while giving rise to the anti-tank/anti-material rifle concept. The designer of the heavy rifle was British Captain H.C. Boys, a designer at the Royal Small Arms Factory at Enfield, and centered around a 13.9mm cartridge (0.55 inches). To protect its development from prying enemy eyes, the weapon was known locally under the code-name of "Project Stanchion" though, eventually, the rifle came to be known by the name of its designer as the "Boys Anti-Tank Rifle".

Good progress on the design was made and subsequent tests proved encouraging with the bullet able to penetrate 1" (25mm) of armor plate. The Boys Rifle was essentially a dimensionally large version of a standard service rifle, a rifle that was intended to be nearly as portable in the field. This was facilitated through use of a spring-based absorber, muzzle brake and monopod (later changed to a spiked/footed bipod). An angled handle at the rear of the butt allowed for a second hand hold when porting the weapon about. The curved detachable box magazine was fitted into the top of the receiver ahead of the action. The weapon was actuated through a manual bolt-action facility as in a traditional bolt-action service rifle. This meant that the bolt-action ejected the spend shell casing while introducing a fresh round into the chamber. The trigger sat within a guard ahead of an angled pistol grip. Initial models sported a double sight arrangement for ranging from 300 yards and 500 yards while subsequent models sported fixed sights.

The weapon was introduced with British infantry elements in 1937. However, enemy tank designs had improved by the time of all-out war in Africa and Europe and it became increasingly clear that the Boys Rifle was an outgoing breed. The weapon managed to be effective during the early stages of the war as enemy armor was still of the light and medium class variety. Against these targets, the Boys Rifle proved its effectiveness. The weapon was especially popular with Finnish Army troops in Finland in 1940 during the "Winter War" against the Soviet Union - the rifle capable of knocking out the Soviet T-26 light tanks being encountered.

A shortened version was developed and issued in 1942 specifically for airborne forces and saw action in Tunisia, where it was proven more or less ineffective due to the reduced velocity inherent in the shortened barrel (also lacking a muzzle brake facility). The weapon was then relegated for use against bunkers, machine gun nests and lightly armored vehicles with success. In the Pacific Theater, the Boys Rifle continued use as it was still effective against the fleet of light and medium combat tanks being fielded by the Imperial Japanese Army. As such, it saw service through the end of the war in August of 1945. Across Europe, the Boys Rifle was eventually superseded by another dedicated anti-tank measure - the famous PIAT anti-tank rocket launcher (detailed elsewhere on this site). PIATs began appearing in useful numbers from 1943 onwards.

Most British and Commonwealth troops disliked the Boys Rifle design due mainly to the massive recoil inherent in firing such a large cartridge. Additionally, the muzzle blast was exceedingly heavy and the noise of the firing action easily gave the position of the firer away. The violent recoil forces led to many bruised necks and shoulders as the rifle was firmly seated against the shoulder when fired. The weapon was also constructed with numerous small screws fit into a relatively soft steel that made maintenance difficult in the field. Nevertheless, the weapon continued use throughout British and Commonwealth ranks with a few examples falling into the hands of German and Japanese troops only too eager to use the weapon against their previous owners. The use of the specialized cartridge, of course, limited enemy operations with captured Boys Rifles.

Picture of the Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR)
Picture of the Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR)

Any available statistics for the Boys 0.55in Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR) are showcased in the areas immediately below. Categories include basic specifications covering initial year of service, country-of-origin and manufacture(s) involved in bringing the weapon to market. Other qualities showcased are related to physical values such as the internal action, available calibers / chamberings, weight and lengths. Global operators are also presented in A-to-Z format as are any model variants available to the series.
Supported Mission Types:
Frontline Issuance
Special Forces
Close Quarters Battle
Designated Marksman/Sharpshooter
Area Effect/Suppression
Indirect Fire
Airspace Denial
Attachment Weapon
National Flag Graphic
National Origin: United Kingdom
Service Year: 1937
Manufacturer(s): Royal Small Arms Factory Enfield (RSA) - UK
Classification Type: Anti-Tank Rifle (ATR) / Anti-Material Rifle (AMR)
Global Operators:
Australia; Canada; China; Finland; France; Greece; Imperial Japan (captured); Ireland; Italy (captured); Luxembourg; Nazi Germany (captured); New Zealand; Philippines; Soviet Union; Taiwan; United Kingdom; United States
Structural - Internal Design, Dimensions, and Weights:


Manually-Operated Bolt-Action System


(Model / Chambering Dependent)
13.9mm (0.55 in)


(Model / Chambering Dependent)
5-round detachable box magazine


1,575 mm

62.01 in


910 mm

35.83 in


Pounds (Unloaded)
35.27 lb

Kilograms (Unloaded)
16.00 kg


Iron Front and Rear

Operating Performance (Typical):

2,900 ft/sec

884 m/sec


10 rpm


1,500 ft

457 m

500 yd

Variants: Series Model Variants
• Mk.I - Circular muzzle break; T-shaped bipod; service load 60g AP projectile at 747m/s.
• Mk.II - Square muzzle break; V-shaped bipod; service load 47.6g AP projectile at 884 m/s.
• Airborne Service Variant - 30" (762mm) barrel with no muzzle break.
• 14mm Pst Kiv/37 - Finnish Army designation