Objections to increasing spiral.
“The use of an increasing or varying turn is obviously injurious, for besides altering the shape of the bullet, it causes increased resistance at the muzzle, the very place where relief is wanted.”
Length and spiral increased.
“Finding that all difficulty arising from length of projectiles, is overcome by giving sufficient rotation, and that any weight that may be necessary can be obtained by adding to the length, I adopted for the bullet of the service weight, an increased length, Diameter decreased.and a reduced diameter, Trajectory lowered.and obtained a comparatively low trajectory; less elevation is required, and the path of the projectile lies more nearly in a straight line, making it more likely to hit any object of moderate height within range, and rendering mistakes in judging distances of less moment. The time of flight being shortened, the projectile is very much less deflected by the action of the wind.”
Proper powder for expanding bullets.
“It is most important to observe that with all expanding bullets proper powder must be employed. In many cases this kind of bullet has failed, owing to the use of a slowly igniting powder, Powder for hardened bullets.which is desirable for a hard metal projectile, as it causes less strain upon the piece, but is unsuitable with a soft metal expanding projectile, for which a quickly igniting powder is absolutely requisite to insure a complete expansion, which will fill the bore. Consequences of imperfect expansion.Unless this is done the gases rush past the bullet between it and the barrel, the latter becomes foul, the bullet is distorted, and the shooting must be bad. Advantages of hexagonal form.If the projectiles used be made of the same hexagonal shape externally as the bore of the barrel internally, that is, with a mechanical fit, metals of all degrees of hardness, from lead, or lead and tin, up to hardened steel may be employed, and slowly igniting powder, like that of the service may be employed.”
Mr. Whitworth’s claims.
Mr. Whitworth does not lay claim to any originality as inventor of the polygonal system, but merely brings it forward, as the most certain mode of securing spiral motion, but he deserves to be honored by all Riflemen, as having established the degree of spirality, the diameter of bore, to ensure the best results from a given weight of lead, and length of barrel.