Field artillery material C / 73
The term field artillery material C / 73 was used to describe the field guns newly introduced after the Franco-German War in 1870/71 . These were the light 8 cm and the heavy 9 cm field cannons .
history
The development of the field artillery material C / 73 goes back to a personal initiative of Alfred Krupp . He had recognized early on that due to the advances in infantry weapons , sooner or later the superiority of the Prussian gun material C / 64 to C / 67 would no longer exist, especially after the introduction of the French Chassepot rifle with its significantly increased range. In addition, the field guns being developed or introduced in the European area surrounding Prussia indicated that significantly higher performance could be expected. The latest French 7 kg breech loader , the Canon de 7 modèle 1867 , had an initial speed of 395 m / s, the Swiss 8.4 cm breech loader a 396 m / s, the newest Russian 8.67 cm Breech loader one of 510 m / s and the English sixteen pound muzzle loader one of 510 m / s. The Prussian 8 and 9 cm field cannons had an initial speed of 341 and 323 m / s at that time.
Based on these findings, Krupp set himself the task of manufacturing a field gun with an initial speed of 1700 feet / sec (535 m / s ) around 1865 . In this intention he was encouraged by the experience he had meanwhile gained in the development of the heavy artillery. However, he had also become aware that the goal could not be achieved with individual corrections to the existing guns, but that the existing system had to be completely put to the test. In his opinion and experience, this included changes in the tube structure, in the area of projectiles and projectile guidance, in the powder and, as a consequence, the construction of a new mount, as the previous wooden mounts would no longer be able to meet the new requirements.
The attempts to manufacture a corresponding 8 cm cannon began in 1868. The first sample delivery to the Artillery Inspection Commission (APK) took place in May / June 1870. As part of this sample delivery, Krupp also presented the first steel mounts . In this version, the carriage walls were riveted together from several steel profiles. In June 1871 another sampling of a modified 8 cm pipe (more precisely 7.87 cm) took place. This tube had a different projectile guidance, an increase in the number of trains and an expansion of the combustion chamber. In a test shooting on July 8, 1871, the target initial speed of 526 m / s was achieved.
When it came to the powder question, he was able to fall back on the experience he had gained in the development of the heavy ring tube constructions. In doing so, he had recognized that the fine-grained powder previously used with its high combustion rate was not suitable for drawn pipes and that a powder with a lower combustion rate was required for these pipes. Based on these considerations, a coarse-grained gun powder with a grain size of 6 to 10 mm and a density of 1.65 to 1.75 was developed in cooperation with the Ritter powder factory in Hamm ad Sieg around 1868. This powder was then modified by Prussia and introduced as coarse-grained gun powder C / 73 with a grain size of 4 to 10 mm.
In the further testing, however, there were again differences of opinion between Krupp and the APK. As early as 1869, Krupp had found in his experiments that the lead jacket previously used to guide the bullet was no longer sufficient above an initial speed of 440 m / s due to its insufficient strength, and to remedy this, he gave the grenades a copper wire guide. Simultaneously with this change, the number of trains has also been increased from 12 to 18. These changes were not accepted by the APK, however, and so they fired grenades with a lead jacket from a gun that Krupp had designed for grenades with a copper wire guide. As a result of this procedure, the initial speed of 526 m / s could no longer be reached later.
After a number of other changes and after the original test gun with a caliber of 7.85 cm had been joined by another gun with a caliber of 8.8 cm, they both received the specifications in 1873 with which they were named "Field Artillery Material C / 73" was introduced. In the period between October 1873 and January 1874, Krupp received orders for around 2500 pipes. These were delivered by June 1, 1875.
technology
Casing tubes were used for the first time with these new guns , as Krupp had made the determination that the strength of the solid tubes was no longer sufficient with a higher load, which was necessary to achieve the desired initial speed. The coat enclosed about 2/3 of the tube of the soul . The soul tube ended at the leading edge of the wedge hole. The so-called “simple Krupp round wedge” in the construction of 1866 was used as a closure. The essential feature of this closure was that the rear surface of the one-piece locking wedge is semicircular and it had a locking screw on top. In contrast to earlier versions, only half a turn of the lock was required to open and close the lock, since in this version the threads of the lock screw were removed on one side and thus the wedge could be pulled out exposed after half a turn. This movement was limited by a limit screw which was installed in the bottom surface of the pipe. The Liderungsring C / 73 was used for leaning. Contrary to the original sampling from 1870, the mounts are now made from pressed steel profiles.
Technical specifications
| Light field cannon | Heavy field cannon | |
|---|---|---|
| Caliber (mm) | 78.5 | 88 |
| pipe | Jacket pipe | |
| Pipe material | Cast steel | |
| Locking system | Round wedge | |
| Pipe weight (kg) | 390 | 450 |
| Floor guidance | lead | |
| Grenade (type) | Wall grenade C / 73 ring grenade C / 76 |
|
| Grenade weight (kg) | 5.07 | 7.0 |
| Range grenade (m) | 6800 | 7000 |
| Shrapnel (type) | Tubular shrapnel C / 73 | |
| Shrapnel weight (kg) | 5.439 | 9.002 |
| Filling balls in shrapnel | 175 | 270 |
| Gun Charge (Type) | coarse-grained gun powder C / 73 | |
| Gun load (kg) | 1.25 | 1.50 |
| Initial speed (m / s) | 465 | 444 |
| Source: Meyers Konversationslexikon | ||
Muzzle energy
The increase in performance actually achieved with the 9 cm cannon can best be illustrated by comparing the muzzle energies (the name at the time was "living force"). While the 6 pounder field cannon C / 61 had a muzzle energy of approx. 36 mt, the 9 cm field cannon C / 73 already had a muzzle energy of approx. 76 mt ( meter ton ). This is a term no longer used today. Today the muzzle energy or bullet energy is given in joules . The previously common designation in mkg or mt was calculated using the formula E = , where M denotes the projectile mass, v the initial speed and g the acceleration due to gravity (9.81 m / s²).
Individual evidence
- ↑ Diedrich Baedecker. Alfred Krupp and the development of the cast steel factory in Essen. Verlag GDBaedecker, Essen 1889, p. 108.
- ↑ William Berdrow: Alfred Krupp and his race . Paul Schmidt publishing house, Berlin 1937, p. 149.
- ^ Krupp 1812–1912 , published by Gustav Fischer. Jena 1912. p. 228.
- ↑ Diedrich Baedecker: Alfred Krupp and the development of the cast steel factory in Essen . Publishing house GD Baedecker. Essen 1889. p. 108.
- ↑ Krupp 1812-1912. Publishing house by Gustav Fischer. Jena 1912. p. 228.
- ^ Georg Ortenburg: Weapons and the use of weapons in the age of armies of millions: Verlag Bernard & Graefe. Bonn 1992. p. 48.
- ^ Krupp 1812–1912 , published by Gustav Fischer. Jena 1912, p. 229.
- ↑ Krupp 1812-1912. Publishing house by Gustav Fischer. Jena 1912. p. 227.
- ↑ William Berdrow: Alfred Krupp and his race . Paul Schmidt publishing house, Berlin 1937, p. 162.
- ↑ The template for this picture comes from: Brockhaus' Konversationslexikon, 14th edition, 1894 to 1896, 7th volume, p. 914 - Fig. 24.
- ↑ However , this was later replaced by the copper wire guide.
- ↑ Meyers Konversationslexikon . 4th edition, Volume 7 from 1885 to 1892, Verlag des Bibliographisches Institut, Leipzig and Vienna.
- ↑ Meyers Konversationslexikon . 4th edition. Volume 10 from 1885 to 1892. Publishing house of the Bibliographisches Institut, Leipzig and Vienna. P. 132, keyword: power.