A shortened, quick-and-dirty translation:

Bullet effects then and now

Kiessling
Das Schiesswesen, Band 10, Nr. 7, S.57-60, 23.7.1908

The old hunters rule was to shoot only at game standing broadside, with the head held high.
In this position the animal offered the vital organs, entrance and exit wound would not be covered by the hide. One intended and got a clear and ample blood trail. The blood trail was the alpha and omega of all shooting.

The hunter did not expect the game to collapse immediately, indeed he did not wish this because such shots usually were foul. Most often, only the extension of a vertebra was hit, the game collapsed immediately, but got up again soon, to vanish in racing flight after some tumbling leaps. In such cases, the position of the hunter was not pleasant. Reloading the muzzleloader took too much time, so the hunting sword had to help – if the hunter was able to reach the animal in time.
Hunters were strictly advised to race to the game immediately and use the sword, without any searching were the bullet sat. If the stag was up again and fought off the hunter, then it was allowed to cut the tendons of the hind legs. – So such shots hitting an extension of a vertebra were dreaded for good reason; and if sometimes the hurry was in vain, then still there was no reason for triumph. The stag had been hit in the spine, maybe even in the head, or both front legs were broken.
So it was expected that the game did not fall with the shot, but went off in racing, but evidently sick flights. Then the bullet strike had already told its glad message, and the hunter could lovingly reload his rifle, to then examine the tracks and to plan the search. The experienced hunter never departed from the rule to shoot only broadside animals, for he knew that only then the energy of the rifle was sufficient to guarantee success.
Diagonal shots lacked in penetration, or they would at least not cause massive destruction of vital organs and quick death. Game that was hit in such way was living on for hours, even days, was chased around for hours by the dog, and finally it was lost somewhere, because the dog could not hold the track, due to lack of a blood trail. Such cases happened quite often .....
Hitting the lung tips ort he liver was quite acceptable, even if the game was still alive for hours. The pure gut our ancestors did not like – except they wanted to see an experienced dog at work. But even back then not every dog, especially not a young dog was working in an exemplary manner.
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It is a fact that with our (modern) bullets game can be barbarically destructed, and this will almost always happen when strong bones in combination with thick muscles are hit......And so, as always, the world is turning a circle: we also prefer broadside shots, but with the opposite reason: our ancestors tried to cause as much destruction as possible, we want to minimise it.
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