Improvements in Projectiles for Rifled Ordnance.
Year: 1895

page_text: Date of Application, 18th June, 1895-Accepted, 17th Aug., 1895
COMPLETE SPECIFICATION.
Improvements in Projectiles for Rifled Ordnance.
I, ELIAS MATTISON JOHNSON, of Spuyten Duyvil New York, County and
State of New York, United States of America, Manufacturer do hereby declare
the nature of this invention and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement :-
Fig. 1 is a side elevation of a projectile of my improved construction;
Fig. 2 is a longitudinal sectional view through the axis of the same;
Fig. 3 is a top view of the projectile with the cap removed and
Figs. 4, and 6 are detail views illustrating various modifications in the shape
of the cap and the manner of attaching it to the projectile.
Like letters of reference designate corresponding parts in all the figures.
My invention relates to projectiles for rifled ordnance, and while not limited in
its application to, yet is more especially intended for, armor piercing projectiles;
that is to say; conoidal projectiles adapted to penetrate the armor-plates of ships
of war, floating batteries, and fortifications protected by armor plates of modern
construction.
As is well known, modern armor-plates of the more approved patterns as now
produced in Europe and in the United States are hardened on the exterior surface
to a depth of from half an inch to one inch and a half (more or less) by various
processes among which may be mentioned the so-called "Harveyizing" process,
the "Campbell" (or Sheffield) process, and several other processes, both patented
and secret, which appear to have met with some degree of success in being able to
resist penetration by special armor-piercing projectiles, fired from heavy-power
guns, specially constructed for the purpose by permitting the use of heavy charges
of high explosives. An examination of the projectiles after firing, seems to show
that the resisting power of these modern plates is due to the fact, that as the hard
point of the projectile strikes the hardened surface of the plate against which it is
fired, the point of the projectile becomes " upset" by the blow at the moment of
impact, and thus loses, in a great measure its power of penetrating the softer
metal underlying the hardened exterior surface of the plate. Now, if this
66
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upsetting of the hard point at the moment of impact with the hardened surface
of the armor-plate can be prevented, and the shape of the point sustained and
kept intact while the hardened surface of the plate is being pierced, then the
projectile would have no difficulty in penetrating the underlying softer metal and
completely piercing the plate, so that the projectile, if of explosive character would
have reached the point where it can do most effectual damage prior to bursting or
explosion, instead of exploding practically exteriorly to the armor-protected sides
of the vessel and thus doing comparatively little execution.
My invention is based upon this theory, and experiments have demonstrated that
it is correct. My improvement, therefore, consisting broadly in the combination
of a pointed projectile (having a hard point) of a detachable supporting and
sustaining cap, recessed on its under side so as to overlap and cover the point of
the projectile and adapted to sustain and support said point at the moment of
impact with the hardened surface of the armor against which the projectile is fired
so that the point cannot fly off or become "upset" by the blow of impact with
the plate but will be supported and its shape sustained while the hardened surface
of the plate is being pierced.

page_text: On the accompanying drawing, the reference-letter A denotes the cylindrical
body of a projectile (either solid or hollow). B the conoidal head, and C the
head point or apex, which on firing the projectile against a modern armor-plate,
first strikes the hardened surface of the plate.
Upon this hard point C, I place a cap D, of any suitable metal or grade of
metal, and of any desired shape exteriorly; but recessed on its under side as
shown at D', so that it will overlap and fit upon the point C. To prevent this
cap D from becoming detached during the flight of the projectile through the air
(or water), it can be fastened to the head of the projectile around the point in
various ways as shown for example in Figs. 1, 2 and 3, in which I have shown the
supporting cap D attached to the conoidal heat B of the projectile by means of
short metal bolts c (preferably three in number, although there may be more or
less), which are fastened obliquely into the sides of the cap D, so as to project
with their inner erds into the recess D' and into apertures in the conoidal head B,
around and below the point. But the method or means of fastening the supporting
cap Dupon the projectile, as well as the shape of the cap, may be varied or
modified in many ways without departing from the spirit of my invention.
Thus, in Figures 1 and 2, I have shown, as examples, the sustaining-cap D with
a pointed head d; while in Figure 4, I have shown cap D with a rounded or semi-
spherical head d'; in Fig. 5 thead . Again, instead of the bolts e for attaching
D is flat; and in Fig. 6, I have shown cap D
with a concave or recessed
the supporting-cap D to the projectile as illustrated in Figs. 1, 2 and 3, dovetailed
bolts or keys may be used, as shown in Figure 4, fitting into dovetailed recesses in
the conoidal head of the projectile below the point C; or hook-shaped fastenings
may be used, as illustrated in Fig. 5 or a band or hoop e may be used for connecting
cap D to the conoidal head B of the projectile as illustrated in Fig. 6.
In other words: I desire it to be distinctly understood, that I do not confine or
limit myself to any particular exterior shape or configuration of the supporting
cap D, nor to any particular means for or method of fastening said cap detachably
upon the head of the projectile.
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Experiments have demonstrated that this recessed supporting cap D will
effectually support and sustain the hard impact-point C of the projectile, so that
this cannot fly off, "flow" or become "upset" at the moment of impact with the
hardened surface of the plate. It would appear that, at the moment of impact,
the fastenings by which cap D is attached to the projectile break or become
disrupted thus severing the connection between the cap and the projectile, and
spreading or enlarging the cap laterally, so as to form, so to speak, a supporting
ring or circular sleeve around the projectile through which this enters and pierces
the plate. It has been demonstrated that the metal of the cap D, acting in this
manner will effectually support the point C and sustain its shape by such support,
not only, at the moment of actual impact, but while the point penetrates the
comparatively thin hardened outer surface or hard skin of the plate after the
piercing of which the softer metal of the plate which underlies its hardened surface
will of itself support the point and prevent it from "flowing" or upsetting
during the penetration of this softer metal which forms the body of the plate.
I am aware that so-called 66 compound projectiles that is to say: projectiles
composed or built up of several separate and separable sections adapted to break
apart and scatter after the projectile leaves the muzzle of the gun and during its
Hight towards the point aimed at for small arms have been made before, in which
the several separable parts or sections are held together either by soldering, or by
a small cap which overlaps and is fastened to the front end of the sectional
bullet; but both the construction and the result of such a device differs very
essentially from my invention which has relation to an altogether different class or
type of projectiles, quite the reverse of "separable" namely projectiles, which
shall remain solid and in one piece not only during their flight through the air, but
even after actual impact and until penetration has been effected not until then is it
desirable that a projectile of the "armor piercing" type, to which mine belongs,

page_text: should break and scatter. This is a fundamental difference, and distinguishes
modern "armor piercing" projectile from all others.
"
I am also aware of the United States Patents to Wm. H. Brown No. 376,728
dated January 24th, 1888, and Geo. R. Wilson Jr.; No. 465,230 dated
Dec. 15th, 1891, the former showing a cylindrical body with a conical point
encased throughout its entire length in a jacket or envelope of soft metal,
substantially like the so-called "Lorentz jacketed pocket, and many other
bullets of that type; while the Patent to Wilson specially describes and claims a
projectile with a stepped or shouldered point covered by a hollow (i.e. not solid) or
chambered frangible cap; the frangibility or brittleness of the cap, so that it may
be instantly shattered on impact, being an important and absolutely necessary
feature. I claim neither of these constructions, combinations or arrangements,
which could under no circumstances be applied to, or from an equivalent for, my
invention.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :
1. The combination with an armor-piercing projectile having a hard solid point,
of a detachable solid cap recessed to fit and overlap the point of the projectile
and adapted to support and sustain the same at the moment of impact with the
plate against which the projectile is fired; substantially as and for the purpose set
forth.
2. The combination with an armor-piercing projectile, having a hard solid point,
of a solid supporting and sustaining cap, recessed on its under side to fit and overlap
the point of the projectile and attached detachably to the conoid below the point
by fastenings adapted to break or rupture by the blow of impact; substantially as
and for the purpose set forth.
3. The combination with a conoidal projectile of a supporting and sustaining
cap, recessed on its under side to fit and overlap the point of the projectile, and
attached detachably to the head of the projectile below the point of the same by
fastenings entering apertures or recesses in the head of the projectile and adapted
to become broken or ruptured by the blow of impact; substantially as and for the
purpose shown and set forth.
Dated this 12th day of June 1895.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.