Backing up a bit for the 1st tube test, the German Proof Black Powder used must have the following characteristics:

75% Saltpeter

10% Sulphur

15% Charcoal

and must have a grain size of 1.78mm.

The 1910/1911 Rules called for Special Proof Powders from the United Koln-Rottweil Powder Works.

The 1939 Law for rifle barrels for centralfire cartridges called for 2 shots of Smokeless Powder.

Hochachtungsvoll,

Raimey
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