The PAW 600 (Panzerabwehrwerfer 600, officially designated 8H63) was a lightweight anti-tank gun that used the high-low pressure system to fire hollow charge warheads.

They had started the war with the 3.7 cm PaK 36, which had the advantage of being very light at 328 kg, so that it could be moved a reasonable distance by hand using only its own crew.

Its replacement, the 5 cm PaK 38, offered better performance (though still only marginal against the new threat) but, at 1,000 kg, was at the absolute limit of what the gun's own crew could effectively move into and out of a firing position by hand.

The situation was so bad that, by May 1944, the 14th (Panzerjager) Kompanie of infantry regiments were having their heavy anti-tank guns removed and replaced by the Panzerschreck rocket launcher.

In 1943, a specification was issued for a lightweight anti-tank gun that used less propellant than a rocket or recoilless weapon, yet was sufficiently accurate to hit a 1-meter square target at a range of 750 meters.

In this system, high pressure caused by the combustion of the propellant was confined to the breech section, which was relatively heavy, and did not act directly on the projectile.

The resulting PAW 600 (later redesignated 8H63) gun weighed about 600 kg, less than half that of the 7.5 cm PaK 40, while having comparable armor penetration out to its full effective anti-tank range of 750 meters.

To simplify development and manufacture, the projectiles used were based on the widely used 8 cm Granatwerfer 34 mortar (actual caliber 81.4 mm).

Traditional high-velocity anti-tank guns were very inefficient when employed as field artillery firing explosive rounds in support of the infantry.

The thick projectile walls necessary to withstand high velocities ensured a small explosive payload and the amount of propellent used was wasteful.

It is clear that, had the war in Europe carried on longer, the 8H63 would have been a major factor and would likely have complemented the towed PAK 40 and replaced various 7.5 cm infantry guns in production.

The weapon was used near the River Aller on 14 April 1945, as described in the following account by the official history of 15th/19th The King's Royal Hussars by Major G Courage 15/19H, who was with the regiment on the day.