Artillery / Germany
17-cm Kanone 18 and 21-cm Mörser 18

17-cm Kanone 18 and 21-cm Mörser 18 

When it came to artillery design in the years during both world wars, Krupp of Essen can be regarded as the virtual leaders. The company's sound approach, coupled with the thorough development of innovations, led to some of the most remarkable artillery pieces in use anywhere in their day, and one of these innovations featured on what were two of the most remarkable artillery pieces in service during World War II. This innovation was the 'double recoil' carriage on which the normal recoil forces were first taken up by the orthodox recoil mechanism close to the barrel and then by the carriage sliding inside rails set on the bulk of the travelling carriage. In this way all the recoil forces were absorbed with virtually no movement relative to the ground, and firing accuracy was thus enhanced. Further improvements also ensured that the entire barrel and carnage could rest on a light firing platform that formed a pivot for easy and rapid traverse.

This double-action carriage was used mainly with two Krupp weapons. The smaller was the 17-cm Kanone 18 (actual calibre 172.5 mm/6.79 in) and the larger the 21-cm Mörser 18 (the Germans often followed the continental practice of calling heavy howitzers a mortar). These two weapons were first introduced in 17-cm (6,8-in) form in 1941 and in 21-cm (8.3-in) form in 1939. Both proved to be excellent weapons and demand was such that Krupp had to delegate extra production to Hanomag at Hannover. Of the two weapons priority was at first given to the 21-cm Mrs 18, and a wide range of special projectiles was developed for this weapon, including concretepiercing shells. But with the advent of the 17-cm K 18 it soon became apparent that the 17-cm shells were only marginally less effective than their 21cm equivalents, and that the 17-cm gun had a much greater range (29600 m/ 32,370 yards as opposed to 16700 m/ 18,270 yards). Thus in 1942 priority was given to the 17-cm K 18, production of the 21-cm Mrs 18 ceasing.

But the 21-cm Mrs 18 remained in use until the end of the war, as did the 17-cm K 18 which continued to impress all who encountered it, either as recipients of the 68-kg (149.9-lb) shell or as gunners. In fact the Allies sometimes acted as gunners, for in 1944 some Allied batteries used captured 17-cm K 18s when ammunition supplies for their normal charges were disrupted by the long logistical train from Normandy to the German border. For all their weight and bulk, both the 17-cm (6.8-in) and 21-cm pieces were fairly easy to handle. A full 360° traverse could be made by only one man, and although both pieces had to be carried in two loads the carriage was well equipped with winches and ramps to make the process of removing the barrel from the carriage a fairly light and rapid task. For short distances both weapons could be towed in one load by a heavy halftrack tractor.

Specification 17-cm K 18

Calibre: 172.5 mm (6.79 in)
Length of piece: 8,529 m (27 ft 11.8 in)
Weight: travelling 23375 kg (51,533 lb) and in action 17520 kg (38,625 lb)
Elevation: 0° to +50°
Traverse: on platform 360° and on carriage 16°
Muzzle velocity: 925 m (3,035 ft) per second
Maximum range: 29600 m (32,370 yards)
Shell weight: HE 68 kg (149,9 lb)

Specification 21-cm Mrs 18

Calibre: 210.9 mm (8,3 in)
Length of piece: 6,51 m(21 ft 4,3 in)
Weight: travelling 22700 kg (50,045 lb) and inaction 16700 kg (36,817 lb)
Elevation: 0° to +50°
Traverse: on platform 360° and on carriage 16°
Muzzle velocity: 565 m (1,854 ft) per second
Maximum range: 16700 m (18,270 yards)
Shell weight: HE 121 kg (266,8 lb)
Views: 519
  • Like it
  • 0