Rifle 7.62mm 2A1
Encyclopedia
The Rifle 7.62mm 2A/2A1 is a 7.62mm NATO (7.62x51) calibre bolt-action rifle adopted as a reserve arm by the Indian military in 1963.

The design of the rifle - initially the Rifle 7.62mm 2A - began at the Ishapore Rifle Factory in India, soon after the Sino-Indian War
Sino-Indian War
The Sino-Indian War , also known as the Sino-Indian Border Conflict , was a war between China and India that occurred in 1962. A disputed Himalayan border was the main pretext for war, but other issues played a role. There had been a series of violent border incidents after the 1959 Tibetan...

 of 1962.

The Ishapore 2A/2A1 has the distinction of being the last bolt-action rifle designed to be used by a regular military force other than specialized sniper rifle
Sniper rifle
In military and law enforcement terminology, a sniper rifle is a precision-rifle used to ensure more accurate placement of bullets at longer ranges than other small arms. A typical sniper rifle is built for optimal levels of accuracy, fitted with a telescopic sight and chambered for a military...

s. Due to fluctuating supplies of affordable .303 British ammunition, the Ishapore rifles are becoming increasingly popular with civilian shooters and collectors in Australia, United Kingdom and the United States.

Design

Externally the Ishapore 2A/2A1 rifle was based upon (and is almost identical to) the .303 British
.303 British
.303 British, or 7.7x56mmR, is a .311 inch calibre rifle and machine gun cartridge first developed in Britain as a blackpowder round put into service in December 1888 for the Lee-Metford rifle, later adapted to use smokeless powders...

 calibre SMLE Mk III*
Lee-Enfield
The Lee-Enfield bolt-action, magazine-fed, repeating rifle was the main firearm used by the military forces of the British Empire and Commonwealth during the first half of the 20th century...

 rifle, with the exception of the distinctive “square” (10 or 12 round) magazine. The rifle was designed to allow the British Pattern 1907 (P'07) sword bayonet
Sword bayonet
thumb|300px|right|[[Ishapore 2A1]] Lee-Enfield w/ P1907 sword bayonetA sword bayonet is any long, knife-bladed bayonet designed for mounting on a musket or rifle. Its use is thought to have begun in the 18th century and to have reached its height of popularity throughout the 19th and into the early...

 to be attached. There were other differences to the Ishapore 2A/2A1 rifles that include the use of improved steel (to handle the increased pressures of the 7.62mm NATO round), and a redesigned extractor to cope with the rimless round. Production of these rifles started in early 1960s and is believed to have been discontinued in 1975. The original (2A) design incorporated the Lee-Enfield rear sight which had metric graduations out to 2000 meters. The re-designated "Rifle 7.62mm 2A1" incorporated a more realistic 800 meter rear sight. The stock is recycled from the No. 1 Mk. III armory stock, with the addition of a cross screw forward of the magazine well. Some stocks were salvaged from existing surplus and show artificer repairs where rotted or damaged wood has been replaced, this is especially evident with the recoil draws that often fail over time due to the rifle being rack stored butt down / muzzle up that allows oils and grease to migrate downwards into this critical area.

Additional Facts

The Ishapore 2A and 2A1 rifles are often incorrectly described as ".308 conversions". In fact, the 2A/2A1 rifles are not conversions of .303 calibre SMLE Mk III* rifles: they were designed and built right from the outset to fire 7.62mm NATO ammunition. Although the 7.62mm NATO and commercial .308 Winchester
.308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...

 ammunition are physically interchangeable, these weapons were not designed for use with commercial .308 Winchester ammunition. One of the most noted misconceptions between the 7.62mm NATO and commercial .308 Winchester ammunition; "the .308 Winchester generates significantly higher pressures than 7.62mm NATO ammunition". This is due to incorrectly substituting the SAAMI (piezoelectric transducer) pressure measurement system with the (Copper Units of Pressure
Copper units of pressure
Copper units of pressure or CUP, and the related lead units of pressure or LUP, are terms applied to pressure measurements used in the field of internal ballistics for the estimation of chamber pressures in firearms. These terms were adopted by convention to indicate that the pressure values were...

, "CUP") measurement system. The original specifications for 7.62mm NATO (M80 BALL) ammunition uses the CUP (Copper Units of Pressure) method. The commercial ammunition usually conforms to the SAAMI standards using the (piezoelectric transducer system) AND/OR the (Copper Units of Pressure, CUP) pressure measurement systems.

For example, 7.62mm NATO ammunition that has been subjected to 125°F to -65°F storage conditions can have an average pressure that shall not exceed 55,000 CUP (Copper Units of Pressure). Whereas commercial .308 Winchester ammunition can have a SAAMI
Saami
Saami or SAAMI can stand for:*Sami people*Sami languages*Sporting Arms and Ammunition Manufacturers' Institute...

/ANSI
Ansi
Ansi is a village in Kaarma Parish, Saare County, on the island of Saaremaa, Estonia....

maximum average pressure of 62,000 PSI (piezoelectric method) OR a maximum average pressure of 52,000 CUP (copper units of pressure); both of these measurements from SAAMI are one and the same, they just represent different methods of measuring (such as inches and millimeters).

The real issue is the differences in the NATO vs. COMMERCIAL cartridge cases, typically the commercial cases are thinner than the NATO cases. Firing commercial cases in NATO chambers can possibly lead to problems, such as a ruptured case, because NATO chamber head space is longer. Prior to firing ANY .308 Winchester ammunition through a 7.62mm NATO chambered rifle, it is strongly advised to check the headspace using a "field" gauge for commercial .308 Winchester ammunition. Doing so will ensure that it is truly safe to fire commercial ammunition in a NATO chamber. The simplest and safest solution is to use 7.62mm NATO ammunition exclusively.

External links

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