Stand clear of the backblast area! A shout heard by many soldiers, in many services over the past 60 plus years. The command, commonly made when a man-portable anti-tank weapon is brought to bare, is still being uttered by soldiers who wield the latest generation of the Carl Gustav recoilless rifle.
In 1946 Swedish engineers developed the next generation anti-tank weapon, following the World War II tradition of the British PIAT, U.S. Bazooka and the Wehrmacht Panzerfaust. However, unlike the traditional rocket fired from a smooth tube, Swedish designers adapted a pre-war concept of a rifled tube.
Most rear-loading shoulder-fired anti-tank rocket systems of World War II relied on stabilization from fins when fired from the tube. The Gustav, firing an 84 mm round, used rifling inside the front portion launcher tube to create the in-flight spin that create a large, accurate high explosive round. The larger HE, or high explosive, round was determined as necessary as tank armor advanced through World War II. Additionally, the 84 mm rounds, unlike their 'bazooka' brethren, had a larger propellant charge at the base, creating velocities twice that of fin-stabilized ant-vehicle rockets.
The operation of the Carl Gustav is simple with effective and devastating results, earning it on a continuing place on the battlefield. The operator mounted the tube, with a left mounted off-set sight, to the shoulder. A secondary trooper, who also hauls the 84 mm rounds, acts as a loader. The rear of the Carl Gustav has a Venturi cone which helps dissipate the blast of the firing round.
The loader unlocks and pivots the rear-breach open, slides the round in, swivels the breach back down and locks it into place. With a simple squeeze of the trigger the operator launches an 84 mm HE round out to fixed targets past 600 yards. When fired, the loader unlocks the breach, swivels it out of battery and discards the large spent propellant case.
The Carl Gustav is called recoilless rifle because unlike a rifled firearm, the blast from the propellant gases exit the rear of the tube, as well as pushing the round out the muzzle. This front and rear expansion of gases results in a tamed, balanced recoil for a large caliber weapons system.
Aiming of the post-World War II Carl Gustav was achieved by a simple iron sight. The system fielded today in places like Afghanistan are aimed with modern electro-optical devices or simple 3x magnification. And of course, there are the emergency iron sights, folded down on the left side of the muzzle.
The diversity of rounds fired by the Carl Gustav range from varieties of HE, to dual-warhead, flechette, smoke and illumination.
The first generation Carl Gustav was in Swedish service by 1948, with a second and now third generation in the hands of soldiers around the world. The Carl Gustav still serves with the United States Army Special Operations, Canada, Great Britain, Japan and many other countries, including its parent country, Sweden.