IMPROVEMENTS IN THE MANUFACTURE OF TUBES FOR GUN BARRELS AND OTHER PURPOSES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO THE MANUFACTURE OF RODS OR BABS, AND TO THE RIFLING OF ORDNANCE AND FIRE-ARMS
Year: 1865

page_text: LETTERS PATENT to Gustavus Palmer Harding, of Bohemia House,
Chiswick, in the County of Middlesex, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF TUBES FOR GUN BARRELS AND OTHER PURPOSES, PARTS
OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO THE MANUFACTURE OF RODS
OR BABS, AND TO THE RIFLING OF ORDNANCE AND FIRE-ARMS."
Sealed the 9th March 1866, and dated the 14th September 1865.
PROVISIONAL SPECIFICATION left by the said Gustavus Palmer Harding
at the Office of the Commissioners of Patents, with his Petition, on the
14th September 1865.
I, GUSTAVUS PALMER HARDING, of Bohemia House, Chiswick, in the
County of Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF TUBES FOR GUN BARBELS AND OTHER
PURPOSES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO THE MANU-
FACTURE OF RODS OR BARS, AND TO THE RIFLING OF ORDNANCE AND FIRE-ARMS," to
be as follows:-
My Invention has for its object improvements in the manufacture of tubes
for gun barrels and other purposes, parts of which improvements are also
[Price 8d.]

page_text: applicable to the manufacture of rods or bars, and to the rifling of orduance
and fire-arms, and relates, first, to the employment of an expanding die or
wordle capable of producing different sizes of tubes or rods, or of producing
tapered tubes or rods for gun barrels or other purposes, such tubes or rods in
cross section being of a truly circular form. Heretofore it has been proposed
in the manufacture of tapered tubes to employ a pair of rolls having a
number of tapered grooves formed on their surfaces, by which means, aided
by an internal mandril, tubes were rolled to the form of the grooves in such
rolls.
It has also been proposed in the Specification of a Patent granted to me,
and dated March 3rd, 1864, No. 541, to employ an expanding die or wordle
composed of a number of plates sliding in suitable guides at right angles to
the direction of the draw, and caused gradually to approach or recede from
each other in the working of the machinery, such expanding die being
employed to produce either cylindrical or tapered tubes or rods, but according
to this arrangement it was impossible to produce tubes or rods of a truly
circular section. Now this part of my present Invention consists in the
employment of dies or wordles composed of a number (two or more) of
segmental dies or rollers, having tapered or other shaped grooves formed on
their peripheries, such segmental dies or rollers meeting at their peripheries,
and there producing a die of a truly circular or other desired formed form;
and in order that noribor fin may be produced on the tube or rod being drawn,
I prefer to form the edges of the segmental dies where they touch each other
of a corrugated or irregular form. These segments are placed radially with
their peripheries converging to a central point, and capable of turning upon
bearings in a frame fixed to a flange on the hydraulic cylinder, to the piston of
which, according to one arrangement, the tubes to be drawn are fixed. The
segmental dies are confined to work within grooves formed in a frame,
which is caused to recede from or approach to the centre of the frame, within
which the centres upon which the segments turn are situated by means of a
train of gearing set in motion by a rack acting thereon during the traverse of
the hydraulic cylinder, or such rack may be put out of action and the die or
wordle set by hand to any position to draw cylindrical tubes. I prefer in
carrying out my Invention to work the expanding dies or wordles in pairs in
one machine, each die or wordle in turn acting as a grip to hold the tube
and draw it through the other die or wordle; for this purpose the tapering
gear of the die or wordle then acting as a grip will be put out of gear, and the
segments of which the die is composed will be free to approach each other by
the friction of the tube between them until they have sufficient grip of the

page_text: tube to hold it whilst being drawn. In this arrangement I find it convenient
to employ a pair of hydraulic cylinders mounted in a suitable framing, one die
or wordle being supported in a cross frame between the heads of the cylinders,
the other die or wordle being mounted in a cross head connecting together
the ends of the piston rods; in this case there will be two racks and two sets
of gearing to work the two dies or wordles, the one set being carried by the
cross head connecting the two piston rods, whilst the other set is carried by
the cross frame connecting together the hydraulic cylinders, the mandril on
the one side being carried by a cross frame connecting together the opposite
ends of the cylinders, whilst the mandril on the opposite side is held in another
frame connected to the cross head of the piston rods. I employ supports
mounted in a strong frame in the direction of the length of the mandrils acting
to give support to the stems of the mandrils whilst the tube is being forced
over them, and thereby prevent the mandrils being bent or buckled, such
supports being capable of giving way as the tube approaches them, and of
returning by means of springs or otherwise to their normal position as the
tube recedes therefrom.
When producing rods or bars according to this Invention the mandrils
will be dispensed with. It will be readily understood that tubes or bars of
other or irregular forms or tapers may be produced according to my Invention
by employing segments of dies having corresponding forms of grooves formed
thereon.
My Invention also relates to improved means of rifling tubes for gun
barrels and ordnance. I am aware that it has before been proposed, in lieu of
cutting the rifling of gun barrels, to produce such rifling by drawing them over
a bulb-headed mandril having indentations or ribs formed thereon, such tubes
being afterwards twisted.
It has also been proposed in the Specification of a Patent granted to
Messrs. Christoph, Hawksworth, and Harding, dated October 10th, 1861,
No. 2533, to employ a similar mandril to that just described, but instead of
drawing the grooves in the barrel in a straight direction, and afterwards
twisting the barrel, it was proposed during the drawing to give rotary motion
either to the mandril or to the tube. Now this part of my present Invention
consists in the employment of a mandril having a bulb thereon, on which are
formed either indentations or projections as above described. On this mandril
is formed a cylindrical portion loosely fitting the bore of the tube, and acting
as a guide to maintain the mandril in correct position; during the rifling the
mandril is formed at either end to receive a pivot formed on the end of a fixed
rod, against which the mandril bears whilst the tube is being drawn or forced

page_text: over it; the mandril being free to turn the rifling will be produced of a
pitch corresponding with the pitch of the indentations or projections on the
mandril.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Gustavus Palmer Harding in the Great Seal Patent Office
on the 14th March 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GUSTAVUS
PALMER HARDING, of Bohemia House, Chiswick, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of September, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Gustavus Palmer Harding, Her special licence that I, the said Gustavus
Palmer Harding, my executors, administrators, and assigns, or such others as
I, the said Gustavus Palmer Harding, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, sbould and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF TUBES FOR GUN BARRELS AND OTHER
PURPOSES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO THE
MANUFACTURE OF RODS OR BARS, AND TO THE RIFLING OF ORDNANCE AND FIRE
ARNS," upon the condition (amongst others) that I, the said Gustavus
Palmer Harding, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause thesame to be filed in the Great
Seal Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that I, the said Gustavus Palmer Harding, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
for
My Invention has for its object improvements in the manufacture of tube
gun barrels and other purposes, parts of which improvements are als

page_text: applicable to the manufacture of rods or bars, and to the rifling of ordnance
and fire-arms, and relates, first, to the employment of an expanding die or
wordle capable of producing different sizes of tubes or rods, or of producing
tapered tubes or rods for gun barrels or other purposes, such tubes or rods in
cross section being when desired of a truly circular form. Heretofore it has
been proposed in the manufacture of tapered tubes to employ a pair of rolls
having a number of tapered grooves formed on their surfaces, by which means,
aided by an internal mandril, tubes were rolled to the form of the grooves in
such rolls.
It has also been proposed in the Specification of a Patent granted to me
and dated March 3rd, 1864, No. 541, to employ an expanding die or wordle
composed of a number of plates sliding in suitable guides at right angles to
the direction of the draw, and caused gradually to approach or recede from
each other in the working of the machinery, such expanding die being
employed to produce either cylindrical or tapered tubes or rods, but according
to this arrangement it was impossible to produce tubes or rods of a truly
circular section.
Now the first part of my present Invention consists in the employment of
dies or wordles composed of a number (two or more) of segmental dies or
rollers, having tapered or other shaped grooves formed on their peripheries,
such segmental dies or rollers meeting at their peripheries and there producing
a die of a truly circular or other desired form, and in order that no rib or fin
may be produced on the tube or rod being drawn, I prefer to form the edges
of the segmental dies where they touch each other of a corrugated or irregular
form. These segments are placed radially with their peripheries converging
to a central point, and capable of turning upon bearings in a frame fixed to a
flange on the hydraulic cylinder, to the piston of which, according to one
arrangement, the tubes to be drawn are fixed. The segmental dies are con-
fined to work within grooves formed in a frame, which is caused to recede from
or approach to the centre of the frame, within which the centres upon which
the segments turn are situated by means of a train of gearing set in motion by
a rack acting thereon during the traverse of the hydraulic cylinder, or such
rack may be put out of action and the die or wordle set by hand to any
position to draw cylindrical tubes. I prefer in carrying out my Invention to
work the expanding dies or wordles in pairs in one machine, each die or
wordle in turn acting as a grip to hold the tube and draw it through the other
die or wordle; for this purpose the tapering gear of the die or wordle then
acting as a grip will be put out of gear, and the segments of which the die
is composed will approach each other until they have sufficient grip of the

page_text: tube to hold it whilst being drawn. In this arrangement I find it convenient
to employ a pair of hydraulic cylinders mounted in a suitable framing, one die
or wordle being supported in a cross frame between the heads of the cylinders,
the other die or wordle being mounted in a cross head connecting together the
ends of the piston rods; in this case there will be two racks and two sets of
gearing to work the two dies or wordles, the one set being carried by the
cross head connecting the two piston rods, whilst the other set is carried by
the cross frame connecting together the hydraulic cylinders, the mandril on
the one side being carried by a cross frame connecting together the opposite
ends of the cylinders, whilst the mandril on the opposite side is held in
another frame connected to the cross head of the piston rods. I employ
supports mounted in a strong frame in the direction of the length of the
mandrils acting to give support to the stems of the mandrils whilst the tubs
is being forced over them, and thereby prevent the mandrils being bent or
buckled, such supports being capable of giving way as the tube approaches
them, and of returning by means of springs or otherwise to their normal
position as the tube recedes therefrom.
When producing rods or bars according to this Invention the mandrils will
be dispensed with. It will be readily understood that tubes or bars of other
or irregular forms or tapers may be produced according to my Invention by
employing segments of dies having corresponding forms of grooves formed
thereon.
My Invention relates, secondly, to improved means of rifling tubes for gun
barrels and ordnance. I am aware that it has before been proposed, in lieu of
cutting the rifling of gun barrels, to produce such rifling by drawing them
over a bulb-headed mandril having indentations or ribs formed thereon, such
tubes being afterwards twisted. It has also been proposed in the Specification
of a Patent granted to Messrs. Christoph, Hawksworth, and Harding, dated
October 10th, 1861, No. 2533, to employ a similar mandril to that just
described, but instead of drawing the grooves in the barrel in a straight
direction, and afterwards twisting the barrel, it was proposed during the
drawing to give rotary motion either to the mandril or to the tube.
Now this part of my present Invention consists in the employment of a
mandril having a bulb thereon, on which are formed either indentations or
projections as above described. On this mandril is formed a cylindrical
portion loosely fitting the bore of the tube and acting as a guide to maintain
the mandril in correct position; during the rifling the mandril is formed at
either end to receive a pivot formed on the end of a fixed rod, against which
the mandril bears whilst the tube is being drawn or forced over it; the

page_text: mandril being free to turn the rifling will be produced of a pitch correspond-
ing with the pitch of the indentations or projections on the mandril.
Having thus stated the nature of my Invention, I will proceed more fully
to describe the manner of performing the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 isa side view partly in section of a'machine constructed according
to the first part of my Invention. Figures 2 and 3 are two end views.
Figure 4 is a cross section on the line 1, 1, Figure 1. Figure 5 is a sectional
plan of parts of the machine; and Figures 6 and 7 are views to a larger scale
of some of the parts separately. a, a, is the bed plate of the machine; b, b,
are two hydraulic cylinders carried by the standards c, c', which are firmly
fixed to the bed plate a, a; the piston rods d, d, are stepped into the cross
head or frame e, and thence pass to the cross head or frame e', to which they
are firmly secured as shown or by other suitable means. The cross heads or
standards e, el, are connected together by the flanged tubes or cylinders e², e²,
in such manner as to form a strong frame, which in the action of the piston
rods d, d, is caused to slide in the one or the other direction upon the bed
plate a, a, the upper ends of the standards e, el, being guided by the fixed
guide bar f, which is firmly connected to the standards and g. To the
standard c' and between the cylinders 6, 6, is fixed one die or wordle, and to
the cross head or frame e is fixed another die or wordle, each of which
according to my Invention may be used alternately as a grip and as a die or
wordle to produce either parallel or tapered tubes or rods. Each of these
dies or wordles is constructed and worked as follows:-h, h, are segments or
portions of dies, each of which has formed on its periphery a tapered groove
(see Figures 6) in such manner that when four or it may be other number of
such segmental dies are placed together at their peripheries they shall
present
the desired form of die or wordle. Each set of the segmental dies h, h, is
supported in a strong frame or box i, within which they are capable ofturning
upon their centres or axes h' as they are moved in one or other direction by
the box or frame, within the grooves or slots; of which the segmental dies
are confined to work. Each of the framesj is caused to move in one or the
other direction in the following manner :-To each of the frames j are fixed
four or it may be other number of rods j, which have formed thereon screw
threads which work within screw nuts in the centres of toothed pinions k.
The pinions & take into and are driven by teeth / formed on the interior of a
ing, the outer surface of which is also provided with teeth ', which take into
and are driven by a piniou m, on the shaft or axis of which is also fixed a

page_text: bevilled toothed wheel m¹, which is taken into by a bevilled toothed wheel n¹
on the shaft or axis n. Turning with this shaft or axis n is a toothed pinion
ns, which is capable of being moved into or out of gear with the toothed
wheel o' on the axis o by the lever handle n³. On the axis o is also fixed a
toothed pinion 0%, which is taken into by a rack p, from which it receives
motion, and in order that the racks p may be kept in gear with the pinions o²,
supporting wheels n' are employed, acting on the backs of the racksp to press
them towards the pinions o%. One of the mandrils q is fixed to the standard c
and the other mandril is fixed to the cross head or frame e¹, and in order to
give support to a mandril whilst a tube is being forced thereon, and thereby
prevent bending or buckling of such mandril, I employ supports 2' mounted
on axes q² in strong frames q* in such manner that as the tube is being forced
over the head of the mandril in the direction indicated by the arrow in
Figures. 7, the supports q' shall act to give support to the stem of the mandril,
and yet when the tube comes up to the supports q' they shall successively
turn upon their axes q², or otherwise move out of the way to allow the tube to
pass, and then when the tube is being drawn in the contrary direction they
shall return to their normal position in readiness again to offer support to the
stem of the mandril whilst a tube is being forced thereon. The mode in
which these supports q¹ are constructed is shown more clearly at Figures 7,by
which it will be seen that springs q' act to force the supports into their normal
position against a pin q5 in readiness to offer support to the mandril whilst a
tube is being forced thereon, whilst such springs will allow of the supports q¹
moving out of the way of a tube as already described. Water is supplied to
one or other end of the cylinders b, b, by means of pipes 6, 6, the direction of
the water being governed by suitable valves in the valve box B, operated by
a lever connected to the rod B¹, as is well understood; and in order that the
machine may be capable of stopping itself I place on the rod B'suitable stops,
which are acted upon by projections on the sliding frame e, e¹, et. I have not,
however, thought it necessary to show the means employed of stopping and
starting the apparatus, nor the arrangement of valves in the valve box B, as
such will be readily understood and applied by any competent engineer.
I will now proceed to describe the mode in which the machinery will
operate when drawing tapered tubes for gun barrels or other purposes. I will
suppose that the pistons d, d, have moved to their furthest distance in the
direction of the standard g. One end of a tube is inserted in one of the dies,
say that fixed to the standard c', that die is then by throwing the pinion nout
gear with the wheel o' and turning the handlen caused to nip tightly the
tube; the sliding frame containing the other die is then in the action of the
of

page_text: machinery caused to approach the die, which for the time being is acting as a
grip; the tube will by this means be forced over the mandril q fixed to the
standard e', each of the supports q¹ giving way as the end of the tube comes
up to them in succession, until the tube has been forced on to the mandril q to
its fullest extent. The frame e carrying one of the dies will then by reversing
the valves be caused to separate from the frame or standard c', and by the
rack 22 acting on the gearing connected to the die for the time acting as a die
will cause the frame j to move outwards from the standard e or c', and thereby
gradually present a smaller and smaller orifice, through which the tube is
.drawn.
9.
In some cases I propose to act on a length of tube sufficient to form two
gun barrels, and in this case the dies or wordles would alternately act as grips
or dies, so that whilst the one is acting as a grip the other would be acting
as a die, and vice versa. By removing the racks p or by throwing the pinions
n2 out of gear with the wheels o' the dies can be set by means of the handle
n5 to any position to draw parallel cylindrical tubes, and by removing the
mandrils rods or bars may be drawn by the machinery.
Figure 8 represents a section of parts showing a modification of the
segmental dies and die box. In this case the segmental dies are reduced
in width, and at their backs are acted upon by a plate h² pushed up by springs
h³ in such manner as to facilitate the introduction of a tube to be drawn, so
that a tube in being pushed into the die and onto the mandril will simply
press back the segmental dies h, and when the tube is being drawn, the
pressure exerted thereby against the segmental dies will cause them to firmly
grip the tube so as to act either as a die or a grip as is desired for the time
being.
When employing hydraulic machinery of the character described in the
Specification of a Patent granted to Messrs. Cristoph, Hawksworth, and
Harding, dated December 5th, 1862, No. 3262, I fix one set of dies to a
flange on the hydraulic cylinder, whilst the tubes to be drawn are fixed to the
piston thereof, or one set of dies may be fixed to a flange on the cylinder,
whilst another set of dies may be fixed to the piston thereof, as will be readily
understood. It will be readily understood that a different arrangement of
gearing to that shown and described may be employed for operating the
segmental dies, or the dies may be formed from 2 or 3 segments instead of four
or other number, and instead of the dies being formed as shown, they may at
the parts be formed to fit on to a shaft or otherwise.
I will now proceed to describe the means employed in carrying out the
second part of my Invention. Figures 9 and 10 show the means employed in

page_text: carrying out this part of my Invention. a is a mandril having a cylindrical
portion a' fitting loosely the bore of the tube 6 and acting as a guide to hold
the mandril in a correct position during the rifling. a2 is a bulb or enlarge.
ment on the mandril, upon which are formed three or other number of
projections a³ cut to the pitch required for the rifling. The portion a¹ is first
passed into the tube until the bulb a² has entered therein, the tube is then by
means of the flange b¹ drawn over the mandril a, which at one end is held
against a fixed rod c, the pivot c' entering a hole in the mandril a in such
manner that the mandril a may be capable of turning during the rifling
operation; a die or wordle d acts to support the tube being rifled around the
acting portion of the mandril a. By these means as the mandril a is free to
turn, the rifling will be produced of a pitch corresponding with the pitch of
the projections a3 on the bulb or enlargement a³ ; a hole is formed in each end
of the mandril a in order that when a tube has been drawn over it, if desired a
rod may act against the end a¹ to push it back and out of the tube. Instead
of projections a³ being formed on the mandril as shown, other forms of
projections or indentations may be employed as desired.
Having thus described the nature of the said Invention, and the manner of
performing the same, I would have it understood that I make no claim to the
separate parts of the mechanism, nor do I confine myself to the precise details
shown and explained, but what I claim is,-
First, the combined arrangement herein described with reference to
Figures 1 to 8 of the Drawings; and
Secondly, I claim the apparatus herein described with reference to Figures
9 and 10 of the Drawings for rifling the barrels of fire-arms.
In witness whereof, I, the said Gustavus Palmer Harding, have hereunto
set my hand and seal, this Thirteenth day of March, in they ear of
our Lord One thousand eight hundred and sixty-six.
G. P. HARDING. (L.S.)