7.5-cm Feldkanone 16 nA and leichte Feldkanone 18
Almost as soon as the German army began to adopt new field guns in the late 19th century they adopted the calibre of 77 mm (3.03 in) as their standard field gun calibre. In 1896 they produced the C/96 of this calibre, and in 1916 updated and revised the design to produce the 7.7-cm FK 16 (FeldKanone, or field gun, and 16 for 1916).
After 1918 there was a drastic rethink of German weapon practices, and among the changes that emerged from this study was the adoption of a new standard calibre of 75 mm (2.95 in); this calibre was (and still is) a standard field gun ammunition calibre, so the Germans were only following a well trodden path. The Versailles Treaty had left the rump of the German army with a stockpile of the old FK 16s, so in order to modernize these guns they were rebarrelled with new 75-mm (2.95-in) barrels. The guns were then known as the 7.5-cm FK 16 nA, with the nA denoting neuer Artillerie, or new model.
The rebarrelled guns were issued during 1934, initially to horse-drawn batteries supporting cavalry units. The Germans continued to use horse cavalry units until 1945, but by then the FK 16 nA had fallen out of use for it was really a relic of a past era, and was as such too heavy and lacking in mobility for the cavalry role. Instead many were relegated to the training role or were issued to various second-line units. Large numbers were still in service when the war ended, and one fired its way into history when it held up an Allied armoured formation for some time during the fighting near the Normandy beach-heads in June 1944. That particular gun was not destroyed until it had knocked out at least 10 Allied tanks.
Even while the rebarrelling of the old FK 16 carriages was under way a call for a new design of cavalry gun was put out. During 1930 and 1931 both Krupp and Rheinmetall produced designs, and although the Krupp design was finally chosen it was not until 1938 that the first examples were issued for service. The new design became the 7.5-cm leFK 18 (leichte Feldkanone, or light field gun), and it had such modern features as a split trail carriage to increase the on-carriage traverse (so useful for anti-armoured warfare) and a range of ammunition that included a hollow-charge warhead for use against tanks. The leFK 18 was judged to to be a great success. Its range was less than that of the weapon it was intended to replace, and the complex carriage made it an expensive and difficult item to produce. Consequently not many were produced and the emphasis for field artillery calibres changed to 105 mm (4.134 in). However, the leFK 18 was kept in production for export sales to gain influence and foreign currency. Some sales were made to various South American countries and in one of them (Brazil) the leFK 18 is still in limited use.
Specification FKlGnA Calibre: 75 mm (2.95 in) Length of piece: 2.70 m (106.3 in) Weight: travelling 2415 kg (5,324 lb) and in action 1524 kg (3,360 lb) Elevation: -9° to +44° Traverse: 4° Muzzle velocity: 662 m (2,172 ft) per second. Range: 12875 m (14,080 yards) Shell weight: 5.83 kg (12.85 lb)
Specification leFK 18
Calibre: 75 mm (2,95 in)
Length of piece: 1.94 m (76,4 in)
Weight: travelling 1324 kg (2,919 lb) and in action 1120 kg (2,470 lb)
Elevation: -5° to +45°
Muzzle velocity: 485 m (1,590 ft) per second
Range: 9425 m (10,310 yards)
Shell weight: 5.83 kg (12.85 lb)