US2894347A - Fluid cylinder surrounding a stationary barrel - Google Patents

Description

F. H. WOODCOCK 2,894,347 FLUID CYLINDER SURROUNDING A STATIONARY BARREL Filed June 22, 1955 Q N m R M Q T H .mW.WM h if M M W 5 WW me P July 14, 1959 United States Patent Ofiice FLUID CYLINDER SURROUNDING. A,

STATIONARY BARREL 7 Francis Henry Woodcock, Gloucester, England Application June 22, 1956, Serial No. 5915,0811 (Claims, priority, application Great Britain June 25, 1955 3 Claims. (Cl. 42-75).-

This invention relates to small arms and has more particular though not exclusive reference to rifles, especially small-bore rifles.

The barrel of a rifle is customarily mounted along a rear portion of its length upon a wood fore-end which is intended to form a rigid support or-bed for-the barrel in order to ensure accuracy of the weapon. However, in practice the wood of the fore-end shrinks and/{or warps withthe result that the barrel and the fore-end only remain in contact at a comparatively small number of separated points rather than over a complete surface and consequently the vibration imparted bythe barrel to the fore-endfurther, loosensthe mounting as. a result of which the accuracy of the weapon and consistency of shooting are impaired.

W h a view to overcoming this defect, constructions have been proposed which provide for adjustment, of the moun ing of, the, rifle barrel on. the fore-end but such devices, do not, really solve. the problem for the; reason that the frequency of vibration of the barrel alters. with he employment of difiierent ammunition, as a result of whichfreqnent adjustmentsv have tor-be, made. Anobject of the present invention. isto overcome the disadvantages of the known constructions and to provide an improved construction of smallarm which will maintain its accuracy, and permit resultant consistency in shooting, over a prolonged period.

A further object is to provide a small arm, particularly a rifle, in which the barrel is supported upon the foreend with the interposition of a liquid damper secured to the latter and which damps the vibrations set up in the barrel when the weapon is fired and minimises the transmission of such vibrations to the fore-end. The damper comprises a rigid cylindrical member surrounding a rear portion of the length of the barrel to contain the liquid in a closed annular chamber between the cylindrical member and the barrel, and resilient locating means, in the form of a sealing ring arranged at each end of the cylindrical member and interposed between the latter and the barrel, which locate the respective ends of the cylindrical member both axially and radially relatively to the barrel and prevent relative sliding axial movement between the cylindrical member and the barrel, said resilient locating means closing the ends of said annular chamber to contain the liquid therein and also maintaining the barrel from contact with any rigid portion of the cylindrical member.

One practical embodiment of the invention, as applied to a small-bore rifle, will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure l is an axial sectional view of the rifle,

Figure 2 is a cross-sectional view of the rifle on the line IIII of Figure 1,

Figure 3 is a detail view showing an alternative method of securing the rifle barrel and damper to the fore-end of the rifle, and

Patented July- 14, 19,59

Figure 4 is a crossrsectional' view on the line. IV-I-V of Figure 3.

Referring to Figures 1 and 2: of the drawings, the rifle 10 shown therein comprises a barrel 11,, fore-end 12, receiver 13 and butt-end 14: The rearward end 11a of the rifle barrel 11 may: be: mounted in the receiver 13 in the normal or any other suitable manner but has dis,- posed around a, rear portion of its length, at least corresponding to the length of thefore-end. 12 of the rifle, a cylinder 15' of steel, aluminium or other suitable material which is of greater diameter than the outer diam;- eter of the rifle barrel 11 so as to provide an annular chamber 16 therebetween when the cylinder is mounted coaxially around the rifle barrel. Such coaxial mount:- ing is achieved in the following; manner. At the forward and rearward ends 15a, 15b of the cylinder 15 its wall thickness. is greater than for the remainder of its length, the effective inner diameter of such ends: being only approximately .010" greater than the outer diameter of the rifle barrel 11. The intermediate portion 150 of the length of they cylinder is machined or otherwise formed to have; a comparatively small wallthickness; so that it is; recessed with respect to the end portions 15a, 15b. of greater wall thickness in order to, form the aforesaid annular chamber 16;

The; rearward end portion 15b of, the outer cylinder. 15 has, a; recess 17 formed, in itsinner periphery to-carry locating; means for the rearward end of the barrel in the.- form of a sealing ring 18-. of resilient mate-rial which bears tightly around the rifle barrel 11' and. provides proper radial location of this end of the cylinder with respectto the. barrel. At the forwardend. of the cylin,-- der 15 the forward end portion. 15a is counterbored at its forward end, as shown at- 19, to form an annular shoulder 20 against which; a resilient sealing ring 21 lies,

. and grips closely around the rifle barrel 11, such sealing;

ring; forming a locating means for theforward end, of; the barrel. The, counterbore 1-9,- of, this forward end portion 15a isscrew-threaded to. receive a. nut 22 the inner end of which bears against a washer 23 which in turn bears against the sealing ring 21 and looks it in position.

The two sealing rings 18, 21 together provide suflicient axial location, as well as radial location, for the outer cylinder with respect to the rifle barrel. The annular chamber 16 is filled with liquid, preferably a heavy oil, escape of the liquid being prevented from either end of the chamber by the sealing rings. A tapped radial bore 24 is provided in the rearward end portion 15c of the cylinder 15 to enable the chamber 16 to be filled with liquid, the bore 24 communicating with the chamber by way of an axial passage 25. Sealing of the bore 24 is eflected by means of a set screw 26.

At its rearward end the outer cylinder 15 terminates just short of the forward end of the receiver 13 and the upper surface of the fore end 12 of the rifle 10 is of arcuate form, as shown at 27 in Figure 2, to provide a mounting for the outer cylinder, the barrel 11 being nowhere in contact with the fore-end. It will be seen that the barrel 11 is virtually suspended at each end by the resilient sealing rings 18, 21 and is not in contact with the fore-end 12 or with any rigid part of the outer cylinder 15, being surrounded by a body of frequency-damping liquid. A downwardly projecting cylindrical boss 28 is secured to the outer surface of the cylinder 15, such boss having a tapped bore 29 to receive the upper end of a securing bolt 30 which passes through a lateral bore 31 formed in the fore-end 12 to form clamping means securing the cylinder 15 and barrel 11 in position on the fore-end.

It is found in practice that the interposition of a liquidfilled chamber between the rifle barrel and its mounting has the effect ofpreventing distortion of the rifle barrel and of damping the vibration set up in the barrel when the rifle is fired, as a result of which greater accuracy and consistency is obtained.

Figures 3 and 4 illustrate an alternative method of securing the cylinder 15 to the fore-end 12. In this arrangement a metal strap 32 is passed around the cylinder 15 and the fore-end 12 to secure them to each other, a clamping bolt and nut 33 being provided which passes through holes formed in the downwardly turned ends 34 of the strap to tighten the latter in position. Preferably a thin strip of felt 35 is interposed between the strap 32 and the cylinder 15. If desired a plurality of straps 32 may be provided at spaced intervals along the fore-end 12.

I claim:

1. A small arm comprising in combination a fore-end, a barrel supported by the fore-end, and a liquid damper, interposed between the barrel and the fore-end and secured to the latter, to damp the vibrations set up in the barrel when the weapon is fired and minimize the transmission of such vibrations to the fore-end, said liquid damper comprising a rigid cylindrical member surrounding the rear portion of the length of the barrel and the wall thickness of which at each of its ends is greater than the wall thickness intermediate its ends, the inter mediate portion of the cylindrical member being formed 4 inner diameter of said end portions of greater wall thickness is'only approximately .010 greater than the outer diameter of the barrel and'the recess at one end of the cylindrical member is formed by counterboring the respective outer end of the cylindrical member to form a shoulder against which the respective sealing ring lies, a nut, the inner end of which'imposes pressure on the respectivesealing ring, being mounted in a screw-threaded outer end of the counterbore to lock the sealing ring in position. I i

3. A small arm comprising in combination a forerend, a barrel supported by the fore-end, and a liquid damper, interposedbetween the barrel and the fore-end and secured to the latter, to damp the vibration setup in the barrel when the weapon is fired and minimise the transmission of such vibration to the fore-end, said liquid damper comprising a rigid cylindrical member surrounding a rear portion of the length of the barrel to contain the liquid in a closed annular chamber between the cylindrical member and the barrel, and resilient locating means, in the form of a sealing ring arranged at each end of the cylindrical member. and interposed between the latter and the barrel, which locate the respective ends of the cylindrical member both axially and radially to have a comparatively small wall thickness so that it is recessed outwardly with respect to the end portions of greater wall thickness in order to form an annular chamber in which the damper liquid is contained, and resilient locating means, in the form of sealing rings which bear tightly around the barrel and are arranged in recesses formed in the inner periphery of each end portion of greater wall thickness of the cylindrical member, which locate the respective ends of the cylindrical member both axially and radially relatively to the barrel and prevent relative sliding movement between the cylindrical member and the barrel, said resilient locating means closing the ends of said annular chamber to contain the liquid therein and also maintaining the barrel from contact with any rigid portion of the cylindrical member.

2. A small arm according to claim 1, wherein the relatively to ,the barrel and prevent relative sliding axial movement between the cylindrical member and the barrel, said resilient locating means closing the ends of said annular chamber to contain the liquid therein and also maintaining the barrel from'contact with any rigid portion of the cylindrical member.

References Cited in the file of this patent UNITED STATES PATENTS v Mefford Feb. 9, 1886

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