The Krummlauf is a bent attachment to the barrel of the German Sturmgewehr  44 assault rifle, which allowed soldiers to shoot over obstacles without exposing themselves to returning fire from the enemy.

Developed in 1943, the Krummlauf became one of Germany’s impractical weapons to turn the tide of the war in its favor. It was first tested when a 20mm curved barrel was attached to an 8mm rifle, which became the baseline for the final design. There were two versions of the Krummlauf, one for infantry and one for armor.

The infantry version has a 30-degree bend to the barrel, which includes a periscope-style mirror, allowing the soldier to have a better aim in the right direction without compromising their position.

The armored version, on the other hand, has four variants, like 30-degree, 40-degree, 60-degree, and a 90-degree bend to the barrel, which was dubbed the “Versatz P”, allowing the rifle to be positioned vertically without taking a lot of space in the vehicle. This was mounted on a hemispherical steel ball with a cup joint, enabling the barrel to be tucked into a port of the vehicle’s armor.

The armored version was first intended to be equipped by the German Elephant tank destroyer, providing the crew with extra protection against enemy soldiers approaching the vehicle with explosive charges, as the tank destroyer has no mounted machine guns.

Despite its innovative intention, the Krummlauf is highly inaccurate when attached to a rifle, and it’s only effective in close ranges. Moreover, the lifespan of the curved barrel is very short since it can only last 300 or 160 rounds when fired, compared to a standard rifle barrel, which can last thousands of rounds.

https://tanks-encyclopedia.com/ww2/nazi_germany/panzerjager_tiger-p_elefant/

https://www.warhistoryonline.com/guns/krummlauf.html

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