The great increase of power due to great increase of initial velocity of the projectile, which has been obtained by the use of smokeless powders in guns which were designed to use brown or black powder, has naturally led to much speculation in regard to the possibilities of the use of smokeless powders in guns constructed to withstand the pressures obtainable with heavy charges of the new explosive. The maximum pressure with charges of smokeless powder, in the guns in use at the present time, is limited to about 16 tons, the same as that obtained by brown or black powders; and the increase of power with these guns is due, mainly, to the absence of a solid residue when smokeless powder is used, giving a larger volume of gas (at the instant of maximum pressure, to expand through the remaining length of bore) than was possible with brown or black powders.
The Willson Disc Gun
Lieut.-Comdr. R. R. Ingersoll, U. S. Navy