Arrangement and method for aligning a sub-calibre barrel

Abstract

The present invention relates to an arrangement for aligning a sub-calibre barrel (1) for use in a principal weapon barrel comprising i) an insert (4) arranged in said principal weapon barrel ii) front securing means (8) for aligning the sub-calibre barrel (1) iii) rear securing means for securing the rear end of the sub-calibre barrel (1), wherein iii.a) said rear securing means comprise a barrel nut (2) in which said sub-calibre barrel (1) is inserted; iii.b) clamping means (3a, 3b) securing said barrel nut (2) to said insert (4) and said clamping means (3a, 3b) in said principal weapon barrel. The invention also relates to a training weapon comprising the arrangement and a method of aligning the training weapon.

Claims

1. Arrangement for aligning a sub-calibre barrel having a longitudinal axis, the arrangement comprising: an insert; one or more alignment screws for aligning the sub-calibre barrel; a barrel nut into which a rear end of the sub-calibre barrel is inserted for securing the rear end; and a front clamping washer and a rear clamping washer positioned on either side of the barrel nut along the longitudinal axis of the sub-calibre barrel, wherein said front clamping washer and said rear clamping washer secure said barrel nut to said insert via one or more fixing screws.

2. Arrangement according to claim 1, wherein the sub-calibre barrel is threadedly affixed in the barrel nut.

3. Arrangement according to claim 1, wherein the sub-calibre barrel is inserted 40 to 60% of the length of the barrel nut.

4. Arrangement according to claim 1, wherein the barrel nut has a rounded, elliptical or spheroidal exterior surface contacting the front and rear clamping washers.

5. Arrangement according to claim 1, wherein a surface of said front and rear clamping washers in contact with the surface of the barrel nut is rounded, elliptical or spheroidal.

6. Arrangement according to claim 1, wherein the one or more fixing screws comprise at least three fixing screws configured for tightening said front and rear clamping washers and said barrel nut to each other.

7. Arrangement according to claim 1, wherein the front clamping washer is tightened to the insert, barrel nut, and the rear clamping washer via one set of screws of said fixing screws drawn from said front clamping washer.

8. Arrangement according to claim 1, wherein the rear clamping washer is tightened to barrel nut and the front clamping washer via one set of screws of said fixing screws drawn from the rear clamping washer.

9. Arrangement according to claim 1, wherein the one or more fixing screws comprise six screws collectively configured to tighten the front and rear clamping washers, said barrel nut and said insert to each other.

10. Arrangement according to claim 1, wherein a bolt is inserted in a rear part of barrel nut.

11. Training weapon comprising the arrangement according to claim 1.

12. Method of aligning a training weapon according to claim 11, the method comprising the steps of: aligning the front end of the sub-calibre barrel by adjusting the one or more alignment screws; securing the rear end of the sub-calibre barrel by positioning said front and rear clamping washers at either side of said barrel nut along the longitudinal axis of the sub-calibre barrel; and securing said front clamping washer to said insert and said rear clamping washer via one or more fixing screws.

13. Method according to claim 12, wherein one set of screws of the one or more fixing screws are drawn from front clamping washer and another set of screws of the one or more fixing screws are drawn from the rear clamping washer.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows a cross section of a barrel nut secured by clamping washers.

(2) FIG. 2 shows a cross section of a sub-calibre barrel insert.

(3) FIG. 3 shows a perspective view of a sub-calibre barrel, barrel nut, and clamping washers.

(4) FIG. 4 shows a perspective view of the exterior surface of a spheroidal barrel nut.

(5) FIG. 5 shows an insert arrangement comprising a sub-calibre barrel.

(6) FIG. 6 shows the rear end of a barrel nut where the bolt is inserted and the rear clamping washer.

(7) FIG. 7 shows a cross section of a front arrangement for securing the front of the sub-calibre barrel by means of screws.

(8) FIGS. 8a-d show cross sections of clamping means with different shapes contacting the barrel nut.

DETAILED DESCRIPTION OF THE INVENTION

(9) FIG. 1 shows a sub-calibre barrel 1, the rear end of which being inserted and secured in a barrel nut 2. Barrel nut 2 is secured by clamping washers 3a and 3b. Clamping washer 3a is secured to insert (adapter) 4 and clamping washer 3b by means of tightening screws 5a. Surfaces C are exposed to pressure by clamping washers 3a and 3b to maintain the barrel nut 2 in place. Screws 5a assist in tightening the clamping washers 3a, 3b together thereby securing the barrel nut 2 and, as a consequence, sub-calibre barrel 1. A bolt 6 inserted in the rear end of barrel nut 2 is attached by means of a bayonet mount.

(10) Preferably, clamping washers 3a, 3b are secured to barrel nut 2 by the following procedure:

(11) Three fixing screws 5a for securing front clamping washer 3a are tightening front clamping washer 3a to insert (adapter) 4. Front clamping washer 3a and insert 4 are provided with through holes through which said three fixing screws 5a tighten insert 4 to front clamping washer 3a. Clamping washer 3b is likewise provided with corresponding holes which are threaded. Fixing screws 5a thus also tighten front and rear clamping washers 3a (which may be provided with threads) and 3b (which are provided with threads) and barrel nut 2. The fixing screws 5a are drawn from clamping washer 3a in FIG. 1. However, fixing screws may also be drawn from clamping washer 3b in which case clamping washer 3a must be provided with threads to allow for tightening.

(12) Sub-calibre barrel 1 is inserted and secured in barrel nut 2. Rear clamping washer 3b, barrel nut 2, and front clamping washer 3a are provided with holes through which fixing screws 5b (not visible in FIG. 1) can be drawn from the rear clamping washer 3b to tighten it to the clamping washer 3a provided with threads whereby barrel nut 2 is held in place relative to the washers (3a, 3b) and the insert 4.

(13) FIG. 2 shows a barrel nut 2 and a gear ring 7 impeding further insertion of sub-calibre barrel 1 into barrel nut 2. The ring 7 may be adjusted to modify the degree of insertion into barrel nut 2 depending on the ammunition used. Clamping washers 3 are tightened to barrel nut 2 and insert 4 by means of screws 5 thereby affixing barrel nut 2 and as a consequence sub-calibre barrel 1. Alignment screws 8 can be adjusted to align the front end of the sub-calibre barrel 1. The alignment screws affixing the front end of the barrel secures the aligning is maintained in the front end of the barrel.

(14) FIG. 3 shows a perspective view of a barrel 1 inserted in barrel nut 2 which is secured by clamping washers 3 by means of screws 5a, 5b. The gear ring 7 on sub-calibre barrel 1 determines the extent of insertion of the sub-calibre barrel 1 into the barrel nut 2.

(15) FIG. 4 shows a perspective view of a spheroidal barrel nut 2 with a length L. Preferably, the spheroidal barrel nut has an exterior spheroidal shape to provide the same contact surface to the clamping washers irrespective of the aligning of the sub-calibre barrel 1. For example, if the aligning of the barrel is adjusted 2 downwards, the barrel nut affixing the barrel will be turned downwards to the same extent as the barrel. Still, however, the contacting surface against the clamping washers will be the same. Therefore, clamping washers having a corresponding contacting surface against the barrel nut will always correspond and fit smoothly to the exterior surface of the barrel nut and safeguard good contacting.

(16) FIG. 5 shows an insert 4 in which sealing ring 9, and membrane 13 are arranged. Sealing ring 9 holds membrane 13 in place to prevent powder gases from entering.

(17) FIG. 6 shows a barrel nut 2 from the rear end thereof. Clamping washer 3b is tightened against barrel nut 2 and clamping washer 3a (not shown) provided with threaded holes adapted for screws 5b drawn from clamping washer 3b.

(18) FIG. 7 shows fixing screws 8 adjusting and aligning sub-calibre barrel 1.

(19) FIGS. 8a-d show different cross sections of clamping means 3, typically a clamping washer, having differently shaped surfaces contacting the barrel nut 2 (compare areas C of FIG. 1). The dotted line of FIGS. 8a-d illustrates the symmetry line (central line) of the clamping means 3. In FIG. 8a, only an edge of the clamping means is in contact with the barrel nut. Still, such contact may be sufficient to maintain the barrel nut fixed such that the sub-calibre barrel remains aligned in a stable way. In FIG. 8b, the portion of the clamping means has been tapered. This portion corresponds to the surface of the clamping means 3 that is in contact with the barrel nut 2 (compare areas C of FIG. 1). This embodiment enables a smoother contact with the barrel nut than in FIG. 8a which still may be sufficient. FIG. 8c shows a rounded edge of the clamping means 3 in contact with the barrel nut 2 (compare areas C of FIG. 1). This also renders the contact between the clamping means 3 and the barrel nut 2 smoother than in FIG. 8a. In FIG. 8d, the whole inner surface of the clamping means 2 has been shaped to smoothly fit the barrel nut 2. While the embodiment of FIG. 8d may be preferred, the embodiment of e.g. FIG. 8a may be sufficient if the aligning of the training weapon need not be maintained for a very long period of time. An advantage of the shape of the clamping means 3 of FIG. 8a may be for example more cost-effective production thereof. Different embodiments may thus be selected depending on the application.