Improvements in the Ignition of Cartridges.
Year: 1895

page_text: Date of Application, 23rd Mar., 1895-Accepted, 27th Apr., 1895
COMPLETE SPECIFICATION.
Improvements in the Ignition of Cartridges.
DANIEL HICKIE of 66 Basinghall Street London E.C. Mining and Machinery
Expert and GEORGE FREDERICK BENTNER of same address Merchant 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:
"
In the use of modern propelling powders such as ❝ nitros or smokeless
compounds certain irregularities have from time to time been noticeable and have
interfered more or less with the action of such powders in sporting, rifle and cannon
cartridges. These irregularities have hitherto been mainly attributed to defects
in the powders especially as the latter were new or not generally understood.
Extended trials and research have however demonstrated that in most instanées
the irregularities referred to arose through the irregular and uncertain action of
the percussion cap and that this was the principal cause of defects which are now
known to have been erroneously attributed to the powders in question.
Irregular action or force of percussion caps with black gunpowder charges was
not of much importance because weak and strong caps had about the same effect
under ordinary conditions on black gunpowder in which detonating or disruptive
action cannot be set up even by the strongest cap whilst a mere spark from the
weakest cap suffices to ignite the latter powder and develop its. force. Nitros and
such like powders and compounds on the other hand (especially those of the
condensed form) possess, in addition to their propelling properties, the property of
being liable to detonation, more or less, through improper initial force of the
percussion cap or primer, a small particle of the charge unduly exploded by the
cap or primer tending to impart a detonating element to the whole, instead of
the required propulsive action, such action of the cap on these powders causes
undue gas pressure, excessive recoil, bad shooting and risk to.users."
The variations in the force and properties of percussion caps are. generally
from 20% to 50%, sometimes they have been found. too weak to bring about
the required ignition of the nitro powder charge and misfires resulted, in other
instances the caps were too violent and unduly exploded the charge especially
when fine particles of the latter had entered the cap-chamber and, in contact
with the cap-composition, received the full force of the cap, became detonated
and imparted the same action to the whole of the charge as referred to above.
Our invention relates to means for overcoming such irregularities as those
referred to for which purpose we employ an-intermediate igniting substance to
be acted upon by the percussion cap or primer. Such intermediate substance,
in its structure and composition, is not subject to the risk of detonation through
the action of a percussion cap of any strength admissible in caps whilst being
at the same time sufficiently inflammable to be ignited by the weakest percussion
caps in use.
The powder charge by this means, being no longer subject to the direct and
irregular action of the cap as heretofore, receives its ignition from the intermediate
igniting substance and through the latter the required propelling action is secured
to the charge and the risk of detonation avoided.
To obtain these results we use a water and air resisting medium made up in the
form of a globule, capsule or disc as may be convenient and composed of celluloid
(free from acid) or other analogous suitable substance which in itself is sufficiently

page_text: inflammable to be ignited by the cap in the manner referred to. We may use this
substance by itself for the purpose named or we may use it as a covering or
receptacle for other igniting substances which give out the required flame for the
purpose aforesaid.
Such additional substance or substances, so enclosed, within the said covering
which is water and air proof, may or may not be hygroscopic because of a
protecting receptacle which is hermetically sealed and non hygroscopic. In
this manner several things may be used that would otherwise not be stable or
suitable for this purpose for instance nitro-cotton wool or powdered nitro-cotton
which are liable to chemical change when exposed to alternations of temperature
or climate, air, moisture or oxidysing agencies, we may also use black-gunpowder
so enclosed because it does not mix with the nitro-charge nor get into the flash
hole. Resinous and other volatile substances may also be used to advantage in the
same manner.
The intermediate globule capsule or disc by itself or with other things enclosed
as aforesaid, is placed in the cartridge case immediately over and in contact with
the flash hole of the cap chamber and may be so placed in any cartridge case, it
may also be placed within the cap-chamber prior to fixing the cap, in either form
it acts on the charge as required and prevents any particles of the latter from
entering the cap-chamber or coming into contact with the cap as the charge was
subject to without such intermediate protection and ignition in the past.
To load cartridges with this intermediate igniting material the globule, capsule
or disc is placed in the cartridge case and pushed down like a wad and the powder
charge is placed over same and the loading completed in the usual manner.
When the cap is fired its flame pierces the intermediate igniter which is acted
upon by the weakest cap or one that would cause misfire to the charge in itself
without this intermediate substance whilst the strongest cap as aforesaid cannot
impart a violent action to the igniting medium nor to the charge accordingly
through this means.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :
1. The use of an intermediate igniter enclosed in a non-hygroscopic-air-tight-
inflammable receptacle in cartridges as described.
2. The use of celluloid as a receptacle for intermediate igniting substances as
described.
3. The use of celluloid, in itself, for intermediate igniting purposes as described.
4. The use of resinous compounds for intermediate igniting purposes as
described.
London 23rd March 1895.
D. HICKIE.
G. F. BENTNER.