Krupp 75mm mountain gun M. 1886

 

 

0K75mmGb 1886_4

 

 

Bulgarian designation :

75-мм нескорострелно планинско оръдие “Круп”

Krupp designation :

7,5cm Gebirgskanone L/13

Calibre :

75mm L/13

Weight of the barrel :

102 kg

Weight of the carriage :

157 kg (original carriage)

244 kg (improved carriage adopted in 1892)

Weight in action :

259 kg with the original carriage

346 kg with the improved carriage

Barrel length :

975 mm

Length of the bore :

845 mm

Length of the rifled part :

700 mm (9.4 calibres)

Barrel grooves

number :

24

depth :

1.25 mm

width :

7 mm

Length of twist :

1875 mm (25 calibres)

Height of the line of fire :

660 mm

Battering charge :

400 g of black powder (full charge)

150 g of black powder (reduced charge)

165 g of smokeless powder (Wόrfel-Pulver C/89)

Common shell

weight :

4.3 kg - charge : 94 g of gunpowder

max. range :

4000 m

Shrapnel  M. 86

weight :

4.355 kg – charge : 55 g of black powder

85 bullets x 15 g

max. range :

2200 m

Shrapnel  M. 96

weight :

4.355 kg – charge : 55 g of black powder

170 bullets x 11 g

max. range :

2200 m

Case shot :

weight :

4.2 kg

max. range :

300 m

Muzzle velocity :

294 m/s with full charge

152 m/s with reduced charge

Remaining velocity :

228 m/s at 2200 m with shrapnel

195 m/s at 4000 m with common shell

Angle of elevation :

500 m – 1° 14’

1000 m – 3° 05’

1500 m – 5° 09’

2000 m – 7° 31’

3000 m – 13° 16’

3500 m – 16° 55’

4000 m – 21° 12’

Angle of descent :

at 100 m – 0° 24’

at 500 m – 2° 04’

at 1000 m – 4° 17’

at 1500 m – 6° 52’

at 2000 m – 9° 52’

at 2500 m – 13° 21’

at 3000 m – 17° 25’

at 3500 m – 22° 06’

at 4000 m – 27° 12’

Length of the line of sight  :

940 mm

Elevation :

+ 20° / - 10° (original carriage)

+ 23° 12’ / - 6° (new carriage)

Wheels

weight :

55 kg

track :

0.83 m

Transport :

4 loads: 1 – barrel (130 kg); 1 – trail; 1 – wheels and shafts; 1 – two ammunition boxes weighting 48 kg each

Ammunition :

in 1889 : 64 common shells, 40 shrapnel, 8 case shots

in 1912 : 138 shells

Remarks :

Slow firing steel mountain gun without mantel, equipped with a cylindro-prismatic wedge breech mechanism with the expanding steel obturation ring system Broadwell. It fired the same projectiles as the 75mm field gun M. 1886, but employed a lighter battering charge. At first the charge was composed by Feinkφrniges Geschόtzpulver (black powder), but later the gun was modified to use the smokeless powder (Wόrfel-Pulver C/89). It was equipped with rope brake to reduce the recoil from 10-12 to 2-3 paces.

Initially this gun was provided with a carriage that proved to be unable to withstand the force of the recoil to such degree that sometime it overturned. Therefore in 1892 it was removed and replaced with a stronger one.

On short rides the old carriage could be towed by two horses without using a limber, by means of a shaft, which could be dismantled to be transported by pack horses.

More pictures from a Krupp catalogue

 

 

 

0K75mmGb 1886_2

0K75mmGb 1886_1