US 1769263 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
July 1, 1930. J JOHNSON 1,769,263
BULLET AND THE MANUFACTURE OF SAME Filed April 12. 1927 FIGS INVENTOR EDWIN.J.JOHNSO N ATTORNEY so separated from the fin.
Patented July 1930 UNITED STATES nnwm .1. Jonson, or MONTREAL, QUEBEC, caiunaf BULLET Am) rim MANUFACTURE or SAME Application filed April 12, 1927, Serial No; 183,156, and'in Canada March25, 192?. v
This invention relates to new and useful improvements in bullets and the method of manufacturing same and the object of the invention is to provide a simple and inexpensive method of manufacturing bullets, the lubricating qualities of which will tend to protect the bore of the-rifle from fouling or corrosion.
Another object is to provide a bullet which, when fired through a rifle, will leave a protective coating on the bore to protect same from rust and the like.
Accordin to my invention, the bullets are made min a round rod of lead, lead alloy, or like material. The rod is passed through a set of rolls or a stamping press which forms the rod into a plurality of cylindrical slugs joined together by thin films. The slugs in this form are subjected 2 to a tumbling process to release the slugs which, when separated from the fins, are treated to a second tumbling process in a suitable rumblin 7 mill. Graphite or such like material is ed into the mill and coats or permeates the surface of the slugs. The
graphite coated slugs are then pressed into bullet form ready for attaching same to-the cartridge cases. In making the bullets, the graphite covered slu'gs are subjected to a very high pressure which forces the graphite into the surface of the bullet, so that the surface becomes impregnated and covered with graphite. The graphite forms a lubricant which prevents the bullet from fouling the bore of the rifle. It also coats the rifling as the bullet passes therethrough and protects the bore from rust and the like.
In the drawings which illustrate my invention I have shown, in diagrammatic form, the various stages through which the bullets pass in the course of manufacture.
Figure 1 is a longitudinal elevation of a rod from which the bullets are made.
5 Figure 2 is a plan view of the slugs connected by fins. I
Figure 3 is a side elevation of the slugs shown inFigure 2. r
Figure4 is a side elevation of the slug Figure 5 is a side elevation of the slug after rumbling in graphite. Figure 6 is a side elevation of the finished bullet.
Figure is an end view of the bullet shown in Figure 6.
Figure 8 is a diagrammatic illustration showing one apparatus which is used for pressing the slugs into bullet form.
eferrmg more particularly to the drawings, 11 designates a round rod of lead, or such likematerial, from which the bullets are made. The rod is fed between a set of rolls or to a press, where it assumes the form shown in Figures 2 and '3, that is a series of cylindrical slugs 12, with rounded ends 13, said ends being connected together by thin fins 14. Theslugs with the fins attached thereto. are then subjected to a tumbling process which separates the fins from the slugs. The slugs 15, free from the fins, are then subjected to a second tumbling process and mixed with graphite which permeates the surface of the slugs and forms an outer coating 6 thereon, as. shown in Figure 5. The graphite coated slu s are then pressed into the shape shown in igures 6 and 7, by the dies shown in Figure 8, that is with the nose 17 rounded off, and a band 18 formed. approximately 80 midway between the nose and the base 19, which may have a depression 20 formed therein, in the usual manner. In Fi re 8 which shows-the preferred form of ullet forming dies, the slug is fed 85 into apertures 21 and 22 formed in the upper and lower swaging dies 23 and 24, andrests against the e ection pin 25. The upper end 26 of the ejection pin is rounded ofi' to press into the slug and form same into the bottom of the bullet with the depression 20 formed therein. It will be seen that the aperture in the upper die is made slightly larger than the aperture in the lower die, so that the band 18 may be formed in the bullet. Fitting into the aperture in the upper die is the swaging pin 27, the lower end of'which is provided with a recess 28 of the same contour as the nose of the bullet.
. The lower edge 29 of the swaging pin is of 100 ing for same ring form, so that the band and the nose of the bullet may be easily formed. An aperture 30 is' provided in the wall of the upper die to allow waste material 31 to be pressed therethrough, as shown.
In operation the swaging pin is moved towards the ejection pin and coming in contact with the graphite coated slug presses same into bullet form, as shown in Figures 6 and 7. The slug is subjected to a very high pressure which forces the excess material through the aperture 30 as shown in Figure 8. The high pressure also forces the graphite into the surface of the bullet until said surface becomes impregnated and covered with graphite. In releasing the formed bullet from the die, the ejection pin is moved through the dies and cuts off the waste material. The finished bullets shown in Figures 6 and 7 are for illustrative purposes only and it will be readily understood that by using different dies, any desired shape of bullet may be obtained.
It will be seen that in this process, the graphite is mixed with the material on the outer surface of the bullet and forms a coatso that when the bullet is fired through the bore of the rifle, the graphite forms a lubricant which assists the passage of the bullet and leaves a deposit of graphite therein, which forms a protectivecoating for the rifling in the bore. The method of manufacturing the ple and produces a bullet of much better lubricating qualities than those at present in use. 1
Having thus described my invention, what I claim 1s:-
A method of manufacturing bullets which consists of passing a rod through a set of rolls and forming therefrom a series of cylindrical slugs with rounded ends, joined together by thin fins, subjecting the connected slugs to a tumbling process to release same from the fins, separating the slugs from the fins, subjecting the slugs to a second tumbling process and mixing graphite with the slugs during said second rumbling process so that their surfaces are coated or permeated with graphite, and finally shaping the bullet.
In Witness whereof I have hereunto set my hand.
EDWIN J. JOHNSON.
shoulder between the bullets is very sim