IMPROVEMENTS IN BREACH-LOADING AND OTHER ORDNANCE
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Christian Collett Steenstrup
at the Office of the Commissioners of Patent with his Petition,
on the 14th September 1869.
I, CHRISTIAN COLLETT STEENSTRUP, Superintending Engineer in the
Royal Norwegian Navy, but at present of No. 9, New Broad Street,
in the City of London, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN BREACH-LOADING AND OTHER ORDNANCE," to.
be as follows:-
The objects of this Invention are more particularly the following:-:
Firstly. To provide a strong, quick, and perfect means of junction
between the different parts of built-up guns, or such having rings
shrunk on the inner core.
And, secondly. To provide a strong, quick, and reliable means of
closing the breach in ordnance.
The nature of this Invention consists essentially of a conical screw
fitting into a corresponding conical nut; the strength, section, and pitch
of the thread may be altered according to circumstances. It will be
understood from the nature of the conical screw that when it all but

page_text: enters its nut or is just in contact a turn or two may cause it to be
firmly secured in its nut. From experiments made I find this kind of
screw amply strong for the purposes intended.
According to the first part of my Invention I proceed to describe its
application to the outer coiled rings of a built-up gun, consisting of a
steel core and wrought-iron rings shrunk successively on to the same.
According to the present practice one fits into the other by means of
tongue and recess. On reflection it will be seen, as practice shews, that
often when these rings cool and contract they grip one part of the core
sooner or firmer than the other, whereby such a ring is drawn to one
side or the other or towards the middle from both ends, thus often
leaving a space between tongue and recess, which detracts from the
solidity of the gun, but when the rings are screwed one into the other
by means of the conical screw and nut formed on their respective ends
the tendency of the contraction, as the thread can only yield inappre-
ciably, is to bind the rings firmly together, forming one solid piece. It
will also be seen that the present plan of joining may by the contraction
put a longitudinally compressive strain on the core not desirable.
As regards the second part of my Invention I proceed to describe it
with reference to breach-loading ordnance of large calibre. The gun
is bored out conically behind and a screw cut in the cone. To this nut
corresponds a conical screwed breach plug, which when screwed home
closes the gun behind, the small forward face of the plug by means of
a copper ring or flange or other suitable means forming the joint against
a recessed face somewhat larger than the bore of the gun. The back of
the cone plug is formed as a neck, which has a spiral thread out in its
circumference of the same pitch as the cone screw.
The neck is con-
tinued behind into a head with a suitable number of holes bored through
it coned towards the outside. Into the spiral fits one or more pegs
fastened in a boss fitting round the neck; this boss is part of a bent
arm having its fulcrum near the periphery of the gun, generally more
forward than the neck. Supposing the cone plug is screwed home in
its nut, by inserting one or more bars or "tommies" in the coned holes
of the head, and, if required, giving them a smart jerk, the cone plug
will at once become loose. One or one and a half turn will suffice to
lift the threads out of contact, and by swinging the cone plug to one
side, turning on its fulcrum, the cannon is open and ready for cleaning
and charging. For the purpose of taking the wear off the joints and

page_text: diminishing the friction the fulcrum pin which is fixed in the arm rests
with its bottom on an adjustable pivot. Another bent arm having
its fulcrum about opposite the other fulcrum carries a cradle for the
projectile. On swinging the cradle arm round the projectile enters
the gun on its cradle so far that a push with a gauge rod will make
the projectile take its proper place in the gun, the external studs on the
projectile fitting into corresponding grooves in the cradle, and all so
arranged that the studs when leaving the cradle continue their move-
ment into the rifle grooves of the gun. The cartridge is then intro-
duced in a similar manner. This construction admits of central firing
by, for instance, having a hole in a slanting downward direction through
the breach plug to the centre of its inner face, which ensures safety to
the gunner.