GB2388178A

GB2388178A - Firearm cartridge laser devive

Info

Publication number: GB2388178A
Application number: GB0307711A
Authority: GB
Inventors: Geoffrey Walsh Turpin; Christine Turpin
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-04-19
Filing date: 2003-04-03
Publication date: 2003-11-05
Also published as: GB0208921D0; GB0307711D0

Abstract

A shotgun fitting device which comprises a battery operated laser light source 1, taking the form of a dummy cartridge, mounted in an axial bore 2 of a sleeve 3 is positioned within the barrel of a firearm so that the light beam produced by source 1 is co-axial with the barrel. Light source 1 is secured relative to sleeve 3 by grub screw 4. The device also includes a rim portion 5 which allows it to be easily extracted from the breech of an associated firearm. The provision of a variety of interchangeable sleeves which have different diameters so as to correspond with various firearm bores is also disclosed.

Description

GB 2388178 A continued (74) Agent and/or Address for Service: Geoffrey

Walsh Turpin Broadlands Farm, Bradworthy, HOLSWOIHY, Devon, EX22 7QY, United Kingdom

2388 1 78

SHOTGUN-FlTTINCflRAING AID The present invention relates to a device primarily for facilitating the fitting of a shotgun to a would-be user, and secondarily for use as a training aid.

For the effective and comfortable use of a shotgun, it is necessary to adjust both the length of the stock and the relative positions of the longitudinal axis of the stock and barrel, or barrels of the shotgun so that when the shotgun is held in a comfortable operating position by the shooter the line of sight of the eyes used by the shooter for pointing the shotgun is parallel to the longitudinal axis of the shotgun. In the case of a single-barrelled, or over-and-under configuration twin barrelled shotgun this axis is the longitudinal axis of the barrel or upper barrel of the shotgun.

At present this so-called fitting operation is done empirically using the developed skills of a gunsmith in a manner analogous to a bespoke tailing operation, which can be time-consuming.

It is an object of the present invention to provide a device for facilitating the fitting of a shotgun to a shooter.

According to the present invention there is provided a device suitable for use in fitting a shotgun to a user of the shotgun comprising a laser light source positioned axially within a sleeve adapted to be a working fit within the, or a, barrel of a shotgun such that the beam of light produced by the laser light source is co-acial with the barrel of the shotgun within which the laser light source is situated.

Preferably the sleeve has the profile of a conventional cartridge case so that it can be inserted into the breech of the shotgun and removed there from by the ejector mechanism of the shotgun, in the usual way.

Preferably the laser light source is provided with a plurality of interchangeable sleeves having diameters, which correspond to the conventional bore sizes of shotguns so that a single laser light source can be used in conjunction with shotguns having bores of different sizes.

The invention will now be described, by way of example, with reference to the accompanying drawing, which is a longitudinal section of an embodiment of the invention. Referring to the drawing, a shotgun fitting aid consists of a battery operated laser light source!, such as those used in light pens and lecture-room pointers, which is mounted in an axial bore 2 in a sleeve 3 which has a profile similar to that of a cartridge and is a working fit in the breech of a shotgun, in which the fitting aid is to be used. A grub screw 4 holds the laser light source 1 in place in the sleeve. A rim 5 on the sleeve 3 enables it to be extracted from the breech of the shotgun by the shotgun's extractor mechanism in the usual way. In practice, a single laser light source 1 may be supplied with a plurality of sleeves 2 of standard bore/ breech sizes so that one laser light source 1 can be used to assist in the fitting of shotguns of any bore.

Three sets of measurements are used in connection with the fitting of a gun to a shooter. These are the length of the stock of the gun; the vertical distance between a rearward projection of the top of the upper barrel of an over-and-under double-

barrelled shotgun or the top rib of a side-by-side double-barrelled shotgun and two upper regions of the stock of the shotgun, known as the comb and the bump, and the sideways displacement of those regions of the stock from the longitudinal axis of the shotgun. These latter sets of measurements are known as the bend and the cast-off respectively. The present invention assists in the optimization of these parameters.

( In use, the fitting aid is inserted into the breech of a barrel of the shotgun concerned, the laser light source is then activated and the shooter points the shotgun at a target.

The position of the laser beam relative to the target is noted, this will then indicate where cast-off in either direction is needed and by how much, it will also indicate if there is a requirement for the bump or comb to be altered and by how much.

Although the invention has been described in relation to the fitting of shotguns, it is equally applicable to target-shooting rifles or pistols.

The invention also may be used to check the truth of gun barrels and the initial adjustment of the sight of sighted guns, in particular the initial setting of telescopic sights, as the laser spot indicated the true point of aim of the gun upon which the sights, or cross-wires in the case of telescopic sights, can then be set.

Claims

1 A device for fitting a shotgun to a user of the shotgun comprising of the operations of inserting into the barrel of the shotgun a dummy cartridge including, a laser light source adapted to produce a beam of light co-axial with the barrel of the shotgun, a person to whom the shotgun is to be fitted to mount the shotgun to his shoulder and simulate pointing the shotgun at a target, noting the point of aim as indicated by the position of incidence on the target of the beam of light from the dummy cartridge indicating where the stock that is fitted to the shotgun should be altered to that which is comfortable for the person to use and provides a true aim for that person.

2 A device for use in a method according to claim 1 of fitting a shotgun to a user, comprising a plurality of cartridge-shaped sleeves having external diameters corresponding to the standard bores for shotguns, each sleeve having an axial bore adapted to receive and locate a laser light source such that the laser light source emits a beam of light which is coaxial with the barrel of the shotgun.