Universal shells for quick-firing 75mm field guns

The supply of field guns with several kinds of projectiles was regarded as a serious inconvenience, which not only made more difficult the supply of ammunition, but also might cause that the right projectile was not on hand when the decisive moment arrived. From the end of the 19th Century the artillery specialists made every effort to invent a universal shell (Eihnheistgeschoss, projectile universel), that would combine the effect of the shell and the shrapnel, even sacrificing part of the effect of each of them. The idea of employ the shrapnel as single shell was thwarted by the lesson of the Russo-Japanese War, since the Russian artillery, equipped only with shrapnel, was not able to destroy or drive out troops in shelter or trenches.

After a lot of unsuccessful attempts, the problem was solved in 1903 by the Dutch artillery officer Pieter Daniel van Essen. Its projectile was a shrapnel with rear burster (s), whose head had a chamber containing the bursting charge (o), a smoke-producing charge (f) and a detonator (d). With time fire, the charge threw the bullets and the head, which, hitting the target, burst by means of the percussion mechanism of a double acting fuze; with percussion fire, the bursting charge detonated, causing the bursting of the whole projectile.

The patent (D.R.P. 156.189, 8 February 1903) was soon bought by the German firm Ehrhardt (Rheinmethall) that introduced its new kind of projectile under the denomination of Brisanzschrapnell Ehrhardt-van Essen. From 1903 to 1910, Ehrhardt uninterruptedly tried to improve its H.E. shrapnel, producing five different models, with the purpose to increase the effect of the bursting charge. Ehrhardt introduced also another kind of universal shell, this time developed from a H.E. shell. It was the Streubrisanzgeschoss (D.R.P. 229.359, 11 December 1903), a segment shell, where a little high explosive buster served to propel the segments in front of the projectile forward with great force, so that when the shell burst in air 100 m short of a shielded gun the segments would pierce the shield. Although well adapted against shielded guns, it was regarded as almost ineffective against animate targets, and it was not greatly appreciated.

Later the German firm Krupp produced its own universal shell, in two different models : the Granatsschrapnell (D.R.P. 224.371, 9 January 1909), with a separate head containing the high explosive, and the Schrapnellgranate, (D.R.P. 247.943, 26 June 1909), with the explosive shared into five different charges. Finally also the French firm Schneider introduced two different kinds of universal shells, P.U.F. (projectile universel simple), with the bursting charge filled among the bullets, and P.U.T. (projectile universel à pétard de tête), with the bursting charge contained in the head of the shrapnel.

The Ehrhardt Brisanzschrapnel was very successful, being tested in many countries and adopted by the United States of America, Holland, Romania and Bulgaria. In 1913 Russia ordered 50,000 rounds and also the Serbian Government was interested in it, but the dealings were interrupted by the outbreak of the World War. On the other hand, Argentina, Chile and Bulgaria adopted the Krupp universal shell. Also Germany and Austria-Hungary for their field gun and field howitzers introduced the Krupp and Ehrhardt universal shells with only some insignificant changes. The Schneider universal shells on the contrary were not greatly appreciated.

In December 1911, after a long series of tests, the Bulgarian Artillery Committee decided to adopt for its field guns the Krupp Schrapnellgranate, choosing the Ehrhardt Brisanzschrapnel for its mountain guns and field howitzers. Nevertheless in October-December 1912, pressed by the urgent needs of the Balkan war, the War Ministry placed an order at Ehrhardt also for the field artillery. At the beginning of the World War, the universal shell was regarded as the main projectile of the Bulgarian artillery.

I don’t know exactly what model of the Ehrhardt Brisanzschrapnel the Bulgarian Army adopted in 1912. If the data given by MUTHER, Der Gerät del leichten Artillerie…, p. 207, are correct, it might be the M. 07, but I’m not sure. At any rate in the next page I describe the later models, which probably the Bulgarian Artillery Committee tested but not adopted in 1910-11. Broadly speaking they were characterized by an increase of the shrapnel to the detriment of the H.E. head, with a corresponding increase of the number of the bullets.

Universal shells data
pattern		head charge	filled charge	base charge	bullets
Ehrhardt	M.03	40 g	=	60 g	200 x 9 g 105 x 12 g
	M. 06	100 g	=	70 g	285 x 9 g
	M. 07	250 g		70 g	260 x 9 g
	c/10 A	70 g	150 g	70 g	310 x 9 g [290 x 9 g]
	c/10 B	70 g	150 g	70 g	305 x 9 g [285 x 9 g]
	c/10 C	70 g	150 g	70 g	335 x 9 g [320 x 9 g]
Streubrisanzgeschoss		148 g	230 segments of different weight
Krupp	Gr-Schr.	40 g	105 g	40 g	300 x 9 g
	Schr-Gr.	195 g			330 x 9 g
Schneider	P.U.S.	=	440 g	80 g	295 x10
	P.U.T.	785 g	300 g	80 g	270 x 10
Remarks The number in bracket shows the number of bullets in Ehrhardt universal shells with steel fuze.

Gr.Schr. Krupp	M. 03	c/10 B	Streubris.
	Ehrhardt

Schneider		Van Essen

Universal shell

Ehrhardt

Krupp