The DSR 1 rifle is designed and manufactured by the German company AMP Technical Services. Currently (2008) it is marketed by DSR-precision GmbH as a specialized sniper rifle for police sharpshooters. This rifle evolved from the now discontinued ERMA SR-100 sniper rifle. It has been adopted by the German GSG 9counter-terrorist unit, as well as by other European special police units and agencies.
The DSR 1 system is configured in a bull-pup design, with a free-floating barrel. The folding bipod is mounted onto upper rails (above the barrel), and the adjustable horizontal front grip is mounted on the lower rails (under the barrel). The rifle features a fully adjustable rear stock and cheek piece. The holder for a spare magazine is installed in the front of the trigger guard to decrease reloading time. The DSR 1 action features a benchrest match-grade, fluted barrel that is quickly interchangeable and is fixed into receiver by three screws. The bolt features six lugs that lock directly into the barrel. The barrel is protected by a ventilated aluminium handguard and is fitted with a muzzle brake (which is very useful when firing full-power, magnum loads). The trigger is two-stage and adjustable. The DSR 1 features a manual, ambidextrous three position safety, located above the trigger guard. For the standard version of the DSR 1 a tactical silencer is available. The silencer is designed to be used with high power ammunition of the DSR 1 chamberings. This silencer effectively suppresses the muzzle blast. Naturally it can not suppress the crack of a supersonic projectile but the direction where the bullet comes from is effectively concealed. The tactical silencer is easily mounted in seconds on the muzzle brake using a quick release lever.
The expected accuracy of the DSR 1 is high: some sources state sub 0.2 MOA accuracy (0.20 inch / 5 mm groups measured center-to-center at 100 yards) with match-grade ammunition and favourable environmental conditions.
The 5-shot groups where obtained by test shooters whilst shooting from the bipod and measured from centre to centre. The table shows that with target factory ammunition the DSR 1 performs in the 0.34 - 0.63 MOA region. If the DSR 1 can perform better under ideal environmental conditions with to the particular rifle tailored handloads to test if the used cartridges and/or the human test shooters are a limiting factor was not tested by Visier magazine.
An article on the DSR 1 in the French Armes & Tir November 2001 gun magazine corroborates the German Visier results. The Armes & Tir test shooters used RUAG target cartridges and could shoot 200 x 300 mm (0.69 x 1.03 MOA) groups at 1,000 m distance with a .338 Lapua Magnum chambered DSR 1 rifle.
The test results reported by the gun magazines Visier and Armes & Tir are good but not exceptional for an expensive high end factory bolt action sniper rifle system.
The DSR 1 Subsonic is a DSR 1 variant.The DSR 1 Subsonic is adjusted to use the subsonic type of ammunition calibre 7.62x51mm NATO/.308 Winchester. Barrel length is 310 mm. The 8 inch twist rate of the barrel is especially adapted to stabilize the heavy projectiles of subsonic ammunition. This ammunition has the same dimensions like standard ammunition of the same calibre. The propellant charge is reduced to keep the bullet velocity (app. 320 m/s) below the speed of sound (340 m/s). This avoids the super sonic crack of standard ammunition. No type of suppressor can reduce the supersonic crack of a bullet flying at supersonic speed. Only use of subsonic type of ammunition is recommended.
The DSR 50 Sniper Rifle is an enlarged variant of the DSR 1. It has an integrated hydraulic recoil damping system in buttstock and a blast compensator. The blast compensator is a linear compensator or a forward venting muzzle brake that also reduces the perceived muzzle blast. The DSR 50 Sniper Rifle is chambered for the .50 BMG (12.7x99mm NATO) cartridge that is significantly larger than the .338 Lapua Magnum cartridge, which is the biggest available chambering for the DSR 1 rifle. Sniper rifles chambered in .50 BMG are often employed as anti-materiel rifles.