US868938A

US868938A - Barrel for portable firearms and cannon with deepened grooves.

Info

Publication number: US868938A
Application number: US38556007A
Authority: US
Inventors: Carl Puff
Original assignee: Individual
Current assignee: Individual
Priority date: 1907-07-25
Filing date: 1907-07-25
Publication date: 1907-10-22
Anticipated expiration: 1924-10-22

Description

No. 868,938. PATENTED OCT. 22. 1907.

G. PUFF.

BARREL FOR PORTABLE FIREARMS AND CANNON WITH DEEPBNED GROOVES. APPLIOATION TILED JULY 25. 1907.

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UNITED STATES PATENT OFFICE.

CARL PUFF, OF SPANDAU, GERMANY.

BARREL FOR PORTABLE FIREARMS AND CANNON WITH DEEPENED GROOVES.

Specification of Letters Patent.

?atented Oct. 22, 1907.

To all whom it may concern:

Be it known that I, CARL Pm, a subject oi the German Emperbr, and a resident of Spandau, Germany, have invented certain new and useful Improvements in Barrels for Portable Firearms and Cannons with Deepened Grooves, of which the following is a specification.

The invention relates to the rifiing of firearm barrels designed to fire projectiles, which, in addition to the usual guiding means, are provided with special driving plates or disks, or the like, of increased diameter, which offer a large pressure area and a smaller sectional charge of the projectile, especially at the beginning of the development of the gases.

Such projectiles have usually been fired until now by means of strongly-conical barrels. It follows that the driving disks, which have a greatly larger diameter than the projectile, must be very long if the projectile is to be properly guided.

According to the present invention, the barrel is cylindrically-bored, while the rifiing grooves are made deeper than is usual and necessary for imparting the desired torque to the projectile, this deepening of the grooves being found in the region of the breech and diminishing toward the muzzle, where the grooves may be of normal depth. I desire to emphasize that the essence and underlying principle of my invention is the deepening of the riding grooves, as contradistinguished from making these grooves shallower than normally. It will be understood that, for any given caliber, a certain depth of groove is absolutely necessary to produce the proper effect upon the projectile,-that is, to cause it to rotate at the proper speed.

I am aware that, heretofore, it has been proposed to cause rifiing grooves, normal at the breech, to become shallower toward the muzzle, where they are necessarily of a depth less than is requisite for giving the proper twist to the projectile. It will be obvious that all such constructions are entirely foreign to my invention, since they lack entirely the essence thereof, namely the deepening of the groovcs,-in fact, they constitute the very antithesis of my construction, shallow'ing instead of deepening the grooves.

In my construction, the deepened portions of the grooves are filled by the driving disk or collar on the projectile, but not by the body of the projectile proper.

The guiding surface of the projectile body enters the grooves only to the usual or normal depth; and the driving disks or collars are compressed as the projectile advances and the grooves shallow to normal depth toward the muzzle. Or the driving disks may be stripped off from the projectile by suitable means located adjacent the muzzle. The object of deepening the grooves toward the breech and causing such deepened portions to be filled by the driving collars is to afford an enlarged pressure area on the projectile, whereby-the gas pressure is considerably reduced, or, if the gas pressure remains the same, the speed of the projectileisincreased.

, The essential features of the invention, and certain of the possible embodiments thereof, will be readily comprehended by reference to the drawings forming a part of this application and in which:

Figure 1 is a diagrammatical longitudinal section through a barrel, in which the grooves shallow from abnormal depth at the breech to normal depth at the muzzle, showing a projectile with its driving disk; Fig. 2 is a cross-section taken through Fig. 1 just in advance of the transition cone; Fig. 3 is a longitudinal section through a. barrel, showing a different form of projectile which may be used; Fig. 4 is a cross-section through a different form of barrel; Fig. 5 is a 1ongitu din-a1 section of a form of barrel in which the driving disk is stripped off the projectile at the muzzle; Fig. 6 is a fragmentary longitudinal section through a barrel, showing a different form of projectile which may be employed; and Figs. 7-9 show other forms of projectiles.

In Fig. 1 of the drawings, 11-!) is the bore proper of the barrel, or the diameter between lands, 0-11 the normal depth of the grooves, ef the deepened part of the grooves, extending through the length g-h, 1Ik the transition cone extending from the rear endsof the grooves to the surfaces of the lands, 1 the body of the projectile, and 2 the driving disk or collar thereof. The length 9-7 of the deepened part of the grooves may be chosen at will. In the diagrammatical illustration, the diameter of the collar 2, as well as the deepening of the grooves, has been somewhat exaggerated. The form and cross-section of the lands may be quite arbitrary, for instance they may be narrower at the rear than toward the muzzle.

In Fig. 3 is shown a projectile 3,11avinga free driving disk 4.

Fig. 4 shows a form of barrel in which the ribs m left between grooves correspond to the diameter of the driving disk, while the narrow ribs n are of the usual depth and cut into the guiding surface of the projectile.

In the form of barrel shown in Fig. 5, the grooves not only shallow from the rear until they have reached normal depth, but are progressively made still shallower, until they vanish toward the muzzle. When the driving disk on the projectile reaches this region, it is stripped off, and may be thrown out through openings 6,

Fig. 6 shows a; projectile having a driving disk 7 which is in the formof a, cup.

Figs. 7 8 and 9 show projectiles with other forms of driving disks.

Having now fully described my invention; what I claim as new is:

A bnrrel for portable firearms and guns adapted to fire projectiles provided with enlarged driving disks, having eeeese rifiing grooves of greater than normal depth at the rear and shallowing to normal depth and finally disappearing 10 at the muzzle, and having also a lateral opening adjacent the muzzle for the discharge of the driving disk.

In testimony whereof I have hereunto-set my hand in presence of two witnesses.

CARL PUFF. Witnesses I'IENRY HAsPEn, WOLDEMAR HAUPT.