Quick-firing vs. not quick-firing guns
On 4 May 1901, cpt. Stefan Slavchev gave a lecture at the officers’ club in Sofia, in which he showed the superiority of quick-firing guns over the guns then in use in Bulgaria. He compared the recently adopted 7.7cm Model 1896 field gun of the German artillery with the 8.7cm field gun of the Bulgarian army.
To calculate the firepower of the latter, he used the firing tables in use in Bulgaria. For the 7.7cm gun, for which similar tables were not yet available, he obtained one, using the ballistic and construction data of that gun and following the method of the leading German artillery expert of the time, gen. Heinrich Rohne (Schießlehre für die Feldartillerie unter besonderer Berücksichtigung der deutschen Feldgeschütze. Mittler & Sohn, Berlin 1893).
To confirm his reflections, he cited the firing tests of a 7.5cm quick-firing Krupp gun carried out in the Meppen proving ground in 1898 and the report of the battle of Ondurman (2 September 1898) published in the Revue d'Artillerie in 1899, in which two mountain guns were compared : a 7.5cm Krupp gun similar to the one in use in Bulgaria and a Nordenfelt quick-firing gun.
Cpt. Slavchev stated that the results of his research could also be applied to the other models of 7.5cm quick-firing field guns in use at the time, namely the French gun mod. 1897, the Krupp gun mod. 1899 adopted by the Swiss artillery and the Ehrhardt gun. There was actually a notable difference between the German 7.7cm gun, which was in fact an accelerated fire, and a true quick-firing gun like the French one. Therefore, the inferiority of the not quick-firing gun was less accentuated than it was in reality, but even so, the need for a rearmament of the artillery with modern quick-firing guns was imperative.
In his lecture, cpt. Slavchev considered the power of both a single shot and the fire of an entire battery under normal and abnormal conditions. The latter were the ones most likely to occur on the battlefield.
The evaluation criteria adopted were the following :
<![if !supportLists]>a) <![endif]>single shot power was defined by the number of people knocked out by a single shot;
<![if !supportLists]>b) <![endif]>battery power was defined by the time it takes for the battery to knock out 50% of enemies with the least amount of projectiles consumption, since it was believed that with similar losses a department would have stopped its action;
<![if !supportLists]>c) <![endif]>normal conditions meant the most favourable conditions for achieving the greatest destruction: the exact distance to the target and the best position of the point of burst in time fire;
<![if !supportLists]>d) <![endif]>abnormal conditions meant the case in which the trajectory did not pass exactly through the target (error in distance) and the burst point of the shrapnel is not optimal (error in height of burst);
<![if !supportLists]>e) <![endif]>during the analysis only time fuze shrapnel was considered, since it was considered the main combat means of neutralizing animated targets.
On the basis of these considerations, cpt. Slavchev came to the following consideration :
<![if !supportLists]>1) <![endif]>if the shot is fired in normal conditions (distance not exceeding 4000 m and known with precision, an interval not greater than 100-150 m), the effectiveness of the single shot of the two guns is the same;
<![if !supportLists]>2) <![endif]>if the shot is made in abnormal conditions, the difference between the two guns is irrelevant overall;
<![if !supportLists]>3) <![endif]>under normal conditions the two batteries employ the same number of shrapnel to accomplish their task, and the quick-firing battery takes only 15’ less than the 8.7cm battery, assuming that six 7.7cm guns fire 48 rounds per minute and six 8.7cm firing with smokeless powder and reduced recoil, 24 rounds : the difference is irrelevant, since in combat it can easily be cancelled by a slower commander, an inadequate order reception, poor shooting observation, etc. – even when the target is larger and requires more time to be neutralized, the difference between the two batteries remains insignificant;
<![if !supportLists]>4) <![endif]>under abnormal conditions, if the 8,7cm battery uses black powder and the recoil is not reduced (rate of fire of 8 rounds per minute), other things being equal, it will be overwhelmed by the quick-firing battery, since the latter will accomplish its task at least 6 times faster;
<![if !supportLists]>5) <![endif]>if the 8,7cm our battery fires with smokeless powder and reduced recoil (rate of 24 rounds per minute), the difference in power between the two batteries will be :
<![if !supportLists]>a) <![endif]>firing with the method used in Bulgaria at the time, with an error of 100 m, it needs three times more time than the quick-firing one to perform the same task;
<![if !supportLists]>b) <![endif]>with progressive fire it will take an average of 41% more shrapnel and 2½ times longer to perform the same task – in this case it doesn’t matter for the two batteries battery, whether or not there is an error in the range, as long as the target is caught in the 200m bracket;
<![if !supportLists]>c) <![endif]>if it fires with the method used in Bulgaria at the time and quick-firing battery uses progressive fire, the latter the quick-firing battery, consuming only 7% more shrapnel, will perform its task in a third of the time it takes the 8,7cm only for the adjustment.
Cpt. Slavchev concluded that under these conditions the rearmament of the Bulgarian artillery with quick-firing guns was extremely urgent, especially since both Turkey and Romania were moving in this direction. However, in case this was not possible at the moment, he made some proposals to reduce as much as possible the inferiority of the non-quick firing guns then available
As for the combat he suggested :
<![if !supportLists]>– <![endif]>to line up in such a way that the firing is carried out in normal and abnormal conditions for the enemy;
<![if !supportLists]>– <![endif]>to switch to fire for effect as soon as possible and to open fire early;
<![if !supportLists]>– <![endif]>to use progressive fire, if not always, due to the large consumption of ammunition, at least in the case of a duel with the enemy’s batteries, especially if they are armed with quick-firing guns;
<![if !supportLists]>– <![endif]>to take care that the duel against quick-firing batteries starts at a distance of less than 3000 m;
<![if !supportLists]>– <![endif]>to perfect as much as possible the training of the artillery officer;
<![if !supportLists]>– <![endif]>to improve the number of horses in batteries;
<![if !supportLists]>– <![endif]>to increase the number of the ammunition wagon of the battery;
<![if !supportLists]>– <![endif]>to increase the percentage of the shrapnel stored in the limbers and the ammunition wagons.
As for the technical point of view, he suggested :
<![if !supportLists]>– <![endif]>to use only smokeless powder;
<![if !supportLists]>– <![endif]>to provide means for reducing the recoil of all field guns;
<![if !supportLists]>– <![endif]>to improve the structure of the 7.5cm shrapnel, as it does for the 8.7cm one.