Röchling shell

Röchling shells were bunker-busting artillery shells, developed by German engineer August Coenders during World War II, based on the theory of increasing the sectional density to improve penetration.

[2] They resembled fin-stabilized arrow shells, but had a discarding flange acting as a driving band instead of fins.

They were regarded as a German secret weapon, and there is speculation that their use was limited in order to reduce the chance of dud shells being recovered and exploited by the Allied forces.

[12] Preserved small-size fin-stabilized prototype of Röchling shell (36 cm long) is since 2020 exhibited in the Museum of Czechoslovakian fortifications,[13] inside the fort Hůrka [cs].

Remnants of full-sized test shells are still visible in the walls of the fort.