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The means adopted by the powder-makers to effect the improvements referred to above have been to lighten the charge of powder, or to compress more fixed gas into a smaller solid weight. This statement more particularly applies to the light (33 grains) bulk powders. By “bulk” is meant those powders that fill the space occupied of old by 42 grain nitro powders in the 3 drams measurer meant for black powder.

But this does by no means embrace all the possible improvements. The 26 grains, and concentrated, powders occupy only about half the space of the bulk powder of whatever specific gravity, and consequently the prospect opens before them of making use of their 80 times power of expansion in the barrel, instead of the 40 expansion power of the bulk powders. This is not as great a possible improvement as it sounds, but it is a large one all the same. At present the coned cases used for this class of nitro powder bring it down below its possibilities, because, as these cones stretch under powder-gas pressure, it is similar in effect to the powder occupying more space in the chamber, and negatives a great part of its capacity for double expansions of other powders within the barrel. At present the makers of condensed powders have not been strong enough to get gun chambers generally shortened to suit them, and thus they are condemned to compete handicapped; but if we were starting to design guns afresh, and were not bound by precedent and the necessity of sometimes borrowing cartridges and lending them, gun chambers and cartridges would be shortened to make use of the possible 80, instead of 40, expansions, with an accompanying still further reduction of lost powder-gas momentum, or loss by “blast,” and its automatic accompaniment of more reduction of recoil.