The Barrett Firearms company was founded by Ronnie Barrett for the purpose of building semi-automatic rifles chambered for powerful .50BMG ammunition, originally developed for and used in Browning M2HB heavy machine guns. Barrett began his work in early 1980s and first working rifles were available in 1982, hence the designation M82. Barrett continued to develop his rifle through 1980s, and developed improved M82A1 rifle by 1986.
The first real success was the purchase of about 100 M82A1 rifles by the Sweden Army in 1989. Major success followed in 1990 – 1991, when US Military purchased numbers of the M82A1 during the operations Desert Shield and Desert Storm in Kuwait and Iraq. About 125 rifles were initially bought by US Marine Corps, orders from US Army and Air Force followed soon. The M82A1 is known for US Military as the SASR – “Special Applications Scoped Rifle” and it was and still is used as an anti-materiel weapon and EOD tool. M82 also can be used to defeat enemy snipers or criminals from standoff range or when targets are behind the cover, but the anti-personnel work is not a major application for Barrett M82.
The latest derivative of the M82 family is the M82A1M rifle, adopted by USMC as the M82A3 SASR and bought in significant numbers. This rifle differs from M82A1 in that it have a full length Picatinny rail that allows a huge variety of scopes and sighting devices to be mounted on the rifle. Other changes are addition of the rear monopod, slightly lightened mechanism and detachable bipod and muzzle brake. The Barrett M82 rifles were bought by various military and police countries from at least 30 countries, such as Belgium, Denmark, Finland, France, Greece, Italy, Mexico, Portugal, Saudi Arabia, Spain, Sweden, Turkey, UK, USA and others. The M82 also is widely used for civilian .50 caliber long range shooting competitions, being fired accurately out to 1000 yards (911 meters) and even further.
The Barrett M82A1 rifle was recently used in 2002 as a platform for experimental OSW (Objective Sniper Weapon) prototype. The M82A1 rifle was fitted with shorter barrel of 25mm caliber, and fired low-velocity high explosive shells developed for 25mm OCSW automatic grenade launcher. The experimental OSW showed an increased effectiveness against various targets but the recoil was beyond the human limitations.
The Barrett M82 is recoil operated, short barrel stroke, semi-automatic firearm. When gun is fired, barrel initially recoils for a short distance being securely locked by the rotating bolt. After the short travel a post on the bolt, engaged in the curved cam track in the receiver, turns bolt to unlock it from the barrel. As soon as the bolt unlocks, the accelerator arm strikes it back, transferring some part of the recoil energy of the barrel to the bolt to achieve the reliable cycling. Then barrel is stopped and the bolt continues back, to extract and eject a spent case.
The receiver is made from two parts (upper and lower), stamped from sheet steel and connected by cross-pins. Heavy barrel is fluted to improve heat dissipation and save weight, and fitted with large and effective reactive muzzle brake. On the earlier models the muzzle brakes were of round cross-section, latter M82 rifles are equipped with two chamber brakes of rectangular cross-section.
Barrett M82A1 rifles are fitted with scope mount and a folding backup iron sights. Every M82 rifle is equipped with folding carrying handle and with a folding bipod M82A1 can be fitted with carry sling but according to those who carried it in the field, M82 is way too uncomfortable to be carried on sling due to excessive length and heavy weight. It is usually carried in special carry soft or hard case.