CA1042267A

CA1042267A - Practice cartridge

Info

Publication number: CA1042267A
Application number: CA224,529A
Authority: CA
Inventors: Siegfried Trillus; Emmerich Uger
Original assignee: Individual
Current assignee: Individual
Priority date: 1975-04-14
Filing date: 1975-04-14
Publication date: 1978-11-14

Abstract

Abstract of the Invention A practice cartridge is provided for use with a high powered rifle in place of standard ammunition for the rifle in order to enable small calibre rim-fire ammunition to be employed.
The device consists of a body having an external configuration substantially the same as that of a standard cartridge for a rifle to which the device is to be fitted, which device is formed internally with a chamber and rifled barrel of dimensions appropriate to the small calibre ammunition to be employed. The chamber is recessed to enable a plug to be inserted therein behind a cartridge, the plug serving to transmit a firing impulse from the firing pin of the rifle to the rim of the cartridge by means of a projection formed on the outer periphery of the inner end of the plug.

Description

22~7 This invention relates to what may be referred to for con-venience as a practice cartridge for use with a high powered rifle.
The purpose of such a cartridge is to substitute for the standard ammunition for the rifle concerned in order to adapt the latter to fire small calibre rim-fire cartridges such as are readily and cheaply available in .22 calibreO This enables the rifle to be used for short range target practice, or for the shooting of small animals at short range~ which would not be feasible with standard ammunition due to the excessive penetration and destructive power of the latter when utilized undçr such circumstancesO Such a facility has advantages not only in increiasing the versatility of an otherwise specialized weaponO but also in enabling a large number of rounds of ammunition to be carried very compactly since the device of the present invention together with a large number ~`
of small calibre cartridges will weigh and bulk no more than two or three conventional cartridges for a high powered rifle.
It is known to provide adaptors for shot guns and large calibre weapons which are in the general form of a cartridge for the weapon concernedO and which adapt the latter for firing cartridges of smaller calibreO However~ such devices have not in general been suitable for use with rim-fire ammunition~ Devices have been proposed in which rim-fire ammunition is accommodated ,: ., , `l by forming the barrel of the device eccentricallyO but such an , I - .
expedient is unsatisfactory from the point of view of accuracy and is only feasible when the difference in calibre between the ` weapon adapted and the ammunition employed is very large.
According to the present invention~ a practice cartridge for a rifle comprises a body of generally similar external con-: . .
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~ 2267 figuration to that of standard ammunition for the rifle with which the device is to be employedO the body having an internal rifled bore extending from a chamber which communicates via a recess with the breech end of the body and is dimensioned to accept a small calibre rim-fire cartridgeO and a removable plug insertable and sealingly slidable in the recess behind a small calibre cartridge placed in the chamber, the plug being formed with at least one projection on the periphery of its inner end adapted to transmit a firing impul~e to the rim of the cartridge~
A preferred embodiment of the invention is described with reference to the accompanying drawingsO wherein:
Figure 1 shows a cartridge in accordance with the invention disassembled into its main parts, Figure 2 is a longitudinal section through the same cartridge when assembledO and Figures 3 and 4 are inner and outer end views of a plug portion of the cartridge.
Referring to the drawingsO a practice cartridge comprises a body 1 whose external configuration resembles that of a round of rifle ammunitionO except that the portion of the body correspond-ing to the bullet of a conventional round is tubular rather than bullet shaped. The exact configuration of the body will of course depend, like that of conventional cartridges, on the chamber con-figuration of the rifle with which the cartridge is to be used.
The body 1 should be a snug fit within the chamber of the rifle, a gas tight relationship and optimum fit being ensured by two o-rings 2 received in peripheral grooves S formed in the body.
The configuration of the body includes a base rim 6 such as is

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1~4Z;2~7 customarily provided on rifle cartridyes to enable their extraction ~;

from the rifle chamber.
InternallyO the body 1 is formed with a rifled bore 7 extending through the body from a chamber 8~ The chamber 8 is dimensioned so as to receive a small calibre cartridge 4 of the rim-firP typeO In practiceO this will normally be a ~22 calibre cartridge because of the cheapness and general availability of li : ......
this type of ammunition. The bore 7 will of course also be of ; ~ :

a corresponding calibre.
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The chamber 8 is separated from the breech end of the -cartridge body 1 by a cylindrical recess 9~ which accommodates a plug 3 insertable into the recess behind the small calibre cartridge 4. A gas tight seal between the plug 9 and the cartridge body 1 is ensured by an O-ring lOo The inner surface of the plug 3 is formed with a projection 11 on its periphery~ whilst the outer end of the plug is provided with a softer insert 12.
; In use~ the cartridge of the invention is loaded by removing the plug 3~ inserting a suitable small calibre cartridge into the chamber 8 and replacing the plug 3. The cartridge so prepared may then be used to load a rifle in the usual way in place of a ' conventional cartridge for the particular rifle concerned.
' IndeedO if the rifle concerned is equipped with a magazine, this may be loaded with practice cartridges in accordance with the invention, or even a mixture of such cartridges and conventional cartridges.
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When the practice cartridge is loaded into the breech of the rifle and the latter firedO the firing pin of the rifle strikes - the plug 3, the projection 11 on which in turn strikes the rim

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~L0~ZZ~i7 of the percussion cap of the small calibre cartridge 4, thus detonating the latter. The bullek from the cartridge passes down the bore 7 and thence down the bore of the rifle without touching the latter.
After firingO the practice cartridge is extracted from the ; chamber of the rifle by means of its rim 60 in the same manner as a conventional cartridge. A small diameter ram rod (not shown) is passed down the barrel 7 of the practice cartridge to eject the spent case o~ the cartridge 4 and the plug 3v whereupon the practice cartridge may be reloaded.
The practice cartridge of the invention enables a high powered rifle to be utilized to fire small calibre rim-fire ammunition even though it itself has a centre firing pin. The insert 12 in the plug 10 avoids any damage to the firing pin of a rifle which might occur if it struck the unyielding material of the plug 10, whLcb will be of brass or steel.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A practice cartridge for a rifle comprising a one piece body of generally similar external dimensions to a standard cartridge for the rifle with which the practice cartridge is to be used, the body having an axial internally rifled bore extending between a muzzle at the front of the body and an internal chamber which communicates via a recess with the breech end of the body and is dimensioned to accept a rim-fire cartridge of substantially smaller calibre than said standard cartridge, and a removable plug insertable and sealingly slidable in the recess behind a small calibre cartridge placed in the chamber, the plug being formed with at least one projection on the periphery of its inner end adapted to transmit a firing impluse to the rim of the cartridge, and with an external peripheral groove containing an O-ring whereby to form a sliding seal with the wall of the recess in the body, and the body being formed with widely spaced external peripheral grooves containing O-rings adapted to enter gas-tight engagement with the chamber of a rifle in which the cartridge is loaded.

2. A practice cartridge according to claim 1, wherein the outer end surface of the plug is formed with an insert of softer material whereby to prevent damage to a rifle firing pin striking the plug when the cartridge is fired.