Improvements in Apparatus for Adapting Guns for Use with Miniature Ammunition.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Adapting Guns for Use with
Miniature Ammunition.
We, JAMES RAMSAY, of Park Crescent House, Erith, and THOMAS EDWARD
RIDDLE, of 4, Shady Villas, Avenue Road, Erith, Engineers, both in the County
of Kent, do hereby declare the nature of this invention to be as follows: —
This invention relates to mechanism for mounting guns or practice barrels,
using reduced ammunition for aiming practice, firing practice or drill in the
powder chamber of guns of the obturating type, in which the said powder chamber
is larger in diameter than the breech opening of the gun.
The mechanism is so arranged that the miniature ammunition can be fired by
the same appliances, mechanical or electrical, as that used for firing the charge
in the parent gun. In most cases this can be done by allowing the striker to
impinge upon the percussion cap of the miniature ammunition through the
medium of a firing pin inserted and free to slide in the axial vent. In firing
electrically the firing pin would be insulated from the axial vent and rest on an
electrical primer fitted to the cartridge of the miniature ammunition.
The mechanism is so devised, that after it has been adjusted to suit a given
class of gun, it does not require any further adjustment to allow it to be again
mounted in, the same gun, or any gun of the same class.
The practice barrel is mounted in such a manner as to be self adjusting longi-
tudinally, the operation of closing the breech pushing the barrel forward against
a strong spring, thus ensuring good contact between end of barrel and obturator
The miniature charge may be placed in the barrel and the fired cartridge ex-
tracted therefrom without removing the barrel from the chamber of the gun.
The barrel using the reduced ammunition may be centred and fixed in the
chamber of the larger gun by carrying the said barrel in a frame which takes a
bearing in front end and rear end of chamber. The front end of frame may be
circular in form, small enough in diameter to pass through the breech opening
of the gun, and takes a bearing upon the front end of chamber, or it could be
formed with three or more projections and be centered in a similar manner.
Owing, however, to the alteration in shape which takes place in the chamber
at this point under the action of the gases we prefer to make the front end of
the frame in such a manner that it expands after passing through the breech
opening, and the frame can thus be centered on a larger diameter of the chamber
which is not so readily destroyed by the gases.
This may be done by pivoting three or more arms on the frame in such a
manner that the said arms will centre the frame in and take a bearing upon the
desired diameter of the chamber The arms may, however, be turned upon their
pivot into such a position that they and the frame carrying them will pass through
the breech opening, the arms being returned automatically to the expanded
position by means of a spring or other suitable device.

page_text: To provide for variation in the length of chamber, the arms may be pivoted
on a frame mounted, and free to slide upon the main frame, the position of the
frame carrying arms relative to main frame being adjusted by means of a nut
working into a screw thread formed upon the main frame, or the frame carrying
arms could be screwed on to the main frame.
The rear end of the frame has three or more surfaces inclined to the axis of
frame into which sliding pieces fit and slide. A sleeve with flange against which
ends of sliding pieces take a bearing is mounted on rear end of main frame and
in front of sliding pieces. The sleeve and frame are connected together by a screw
which is fixed longitudinally, but free to revolve in frame, the screw engaging
In a nut in sleeve, or visa versa, so that by revolving the screw the sleeve may be
made to slide upon the frame. The sliding pieces may be held against flange of
sleeve by a spring or other suitable means." 'It will thus be seen that by moving
sleeve on frame as described the sliding pieces may be made to expand or contract
as desired, the object being to contact them to a diameter sufficiently small to
pass through the breech opening, and then to expand them against the chamber
thus centring and fixing the appliance in the gun. Or the sliding pieces may be
expanded by means of a nut working into a screw formed upon the frame, the
ends of sliding pieces bearing against face of nut and nut may be revolved by
means of a pinion mounted on frame and engaging in teeth formed upon outside
of said nut.
The practice barrel slides in the frame being held when the breech is open to
the rear of its firing position by means of a spring. On closing the breech the
barrel is pushed forward as before described.
Where the variation in lengths of chambers is small it will be seen that the
sliding pieces on rear end of frame will centre and fix the appliance without any
further adjustment being required.
Dated this Oth dox of October 1890
JAMES RAMSAY.
THOMAS EDWARD RIDDLE
COMILIEN DE MULTIUATION.
Improvements in Apparatus for Adapting Guns for Use with
Miniature Ammunition.
We, JAMES RAMSAY, of Park Crescent House, and THOMAS EDWARD RIDDLE,
of 4, Shady Villas, Avenue Road, both of Erith, in the County of Kent, Engineers
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 follow-
ing statement:-
This invention relates more particularly to guns of the obturating type in
which the powder chamber is larger in diameter than the breech opening and
has for its object to provide improved apparatus for enabling such guns to be
furnished with practice barrels and thereby adapting them for use with minia-
ture ammunition.
According to our invention the practice barrel is provided with a frame having
supports which are intended to take a bearing near the front and rear ends of
the powder chamber, to centrally secure the practice barrel in place. The sup-
port near the front end of the frame may be of a diameter to fit without adjust-
ment the front contracted portion of the powder chamber, although we prefer to
construct it in such manner that it can be caused to expand after being inserted

page_text: into the powder chamber so as to be centred in the larger diameter thereof. In
the latter case the alteration which takes place in the shape of the front part of
the powder chamber, under the erosive action of the powder gases, will not inter-
fere with the proper centering of the practice barrel.
The support near the rear end of the aforesaid frame of the practice barrel,
is furnished with three or more sliding surfaces which are inclined forwardly
towards the axis of the frame of the practice barrel and upon which surfaces
movable pieces or blocks are adapted to slide by means of suitable mechanism
in order to bring the said blocks against the wall of the powder chamber thereby
securing the frame in a central position and exerting a pressure thereon in a for-
ward direction towards the front support.
In order that our said invention may be clearly understood and readily-carried
into effect we will proceed to describe the same more fully with reference to the
accompanying drawings in which:
Figure 1 is a longitudinal section of the powder chamber of a gun with our
practice barrel mounted therein.
Figure 2 is a transverse section taken approximately on the line 1, 1 of
Figure 1.
Figure 3 is another transverse section shewing a modification.
Figure 4 is a transverse section taken approximately on the line 2, 2 of
Figure 3.
•
In all of the figures like reference letters indicate similar parts.
:
A is the powder chamber; B the practice barrel; C the frame carrying said
barrel; D the front support and E the rear support.
Referring more particularly to Figures 1 and 2, the front support D comprises
a circular plate which is of such diameter as to pass through the breech opening.
of the powder chamber A and take a bearing at the front and smaller end of
said chamber. The said circular plate has an internally screw threaded boss for
enabling it to be screwed to the front end of the frame C in the desired position,
where it is maintained by a bolt d passing through lugs on a split or divided
part of the said boss. The plate can thus be shifted either towards or away from
the muzzle of the practice barrel and so he adjusted in accordance with the length
of the powder chamber of the gun to which it is to be applied Instead of em-
ploying the said plate, we might employ three or more arms or projections ex-
tending from a screwed boss adapted to be secured to the frame C as above .ex-
plained. In this case however it would be desirable to provide means, such as
hereinafter described, for preventing the entrance of the powder gases resulting
from the discharge of the miniature ammunition, into the powder chamber A,
otherwise such gases would tend to corrode the frame and other parts of the
practice barrel exposed to their action.
The rear support E comprises a cylindrical portion e secured to the frame C
and furnished with three radial projections e¹ formed with the inclined surfaces e²
upon which the blocks can slide, the outer ends e of said blocks being bevelled
to lie against the wall of the rear portion of the powder chamber. These blocks
have lugs which are acted upon by springs e abutting against screw plugs e
said springs tending to keep the rear or inner ends of the blocks pressed against
a flanged sleeve e. This sleeve can be caused to slide to and fro along the
cylindrical portion e, of the rear support by turning a spindle which is carried
by a lug and is formed with screw threads engaging with a correspondingly
screw threaded hole in the said sleeve. By turning the spindle e in one direction
the said sleeve will permit the springs e to move the sliding blocks e³ inwardly
to contract the diameter of the rear support and enable it to enter the breech of
the gun. Then by turning said spindle 8 in the other direction the sliding blocks
will move outwardly against the resistance of said springs and the diameter of
the rear support will be enlarged, thereby securing the frame and the practice
barrel in place within the powder chamber. It will be seen that by reason of

page_text: the sliding blocks being forced against the interior surface of the powder chamber
in an inclined direction relatively to the axis of the frame, the latter is pressed
in a forward direction towards the front support D and is therefore very firmly
and effectually held in proper position.
The miniature ammunition can be fired by the same appliances (mechanical
or electrical) as those used for firing the ordinary charge of the gun. For this
purpose we place in the axial vent of the obturator F a loose pin which is
actuated by the ordinary striker f of the gun (Figures 1 and 3) and thereby
operates the striker f¹ of the practice barrel B.
The practice barrel has a fixed collar between which and the front end of the
frame C is located the spring 6. This spring tends to slide the barrel rear-
wardly when the breech of the gun is opened and, when said breech is closed it
keeps the practice barrel pressed firmly against the obturator. 2 is an adjustable
collar for regulating the extent to which the barrel can slide rearwardly under
the action of the said spring.
In the arrangement illustrated in Figures 3 and 4, we have shewn the front
support D constructed to expand after its insertion into the powder chamber A.
For this purpose the said front support is furnished with three pivoted radial
arms which in Figure 3 are shown in their extended position in full lines and
are capable of turning inwardly into the position represented by the dotted lines
to permit the front support to be inserted into the breech of the gun. The said
pivoted radial arms are subject to the action of spring plungers which tend
to turn said arms into their outward or extended position and keep them pressed
against projections or stop pieces d. In order to maintain said arms in their
inward or contracted position until after the front support has been inserted
through the breech opening, we provide a flanged metal ring or hoop adapted
to surround said arms when they are turned inwardly As the front support
enters the breech opening, the flange of said ring comes against the breech open-
ing and is prevented from advancing with the front support into the powder
chamber thus becoming detached from the support, and releasing the said arms.
so that they can assume their extended position within the powder chamber,
In this case we prefer to provide the muzzle end of the practice barrel with a
disc G which enters the bore of the gun and prevents the powder gases resulting
from the firing of the miniature ammunition from returning into the powder
chamber. A disc of this description could also be employed with the fixed support
referred to in Figure 1, if said support were made with arms or projections
as hereinbefore stated.
In Figure 3 we have shewn the rear support provided with modified means for
actuating the sliding blocks e³. That is to say instead of employing a sliding
sleeve e actuated by a screw spindle es as in Figure 1, we employ a rotary sleeve
having screw threads e10 which engage with corresponding screw threads on the
rear support so that the said rotary sleeve works thereon like a nut on a bolt.
The said rotary sleeve is in this case operated by a toothed pinion ell on the
spindle gearing with teeth formed in the flanged periphery of the rotary sleeve.
It will be observed on reference to either of the arrangements illustrated in the
drawings, that when the practice barrel has been inserted into the powder chamber
A, it is only necessary to revolve the spindle es, to cause the practice barrel to
be effectually and firmly fixed centrally within the gun.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what we
claim for adapting guns to fire miniature ammunition is:-
1 The rear support for the practice barrel, furnished with sliding blocks
adapted to move in an inclined direction relatively to the axis of the said barrel
for the purpose specified.
2. The front support for the practice barrel, adapted to expand after insertion
into the powder chamber substantially as and for the purpose specified.

page_text: 3. Apparatus having its parts constructed arranged and operating substantially
as described with reference to either of the arrangements illustrated in the
accompanying drawings for the purpose specified.
Dated this 9th day of July 1900.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.