Information
-
Patent Grant
-
6289782
-
Patent Number
6,289,782
-
Date Filed
Monday, October 25, 199925 years ago
-
Date Issued
Tuesday, September 18, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Jordan; Charles T.
- Chambers; Troy
Agents
- Bechtel, Esq.; James B.
- Van Bergen, Esq.; Peter J.
-
CPC
-
US Classifications
Field of Search
US
- 089 141
- 089 3701
- 089 3704
- 089 17
- 042 7502
- 042 86
- 042 7501
- 042 103
- 042 100
- 042 102
- 033 246
- 033 237
- 033 233
- 033 248
- 033 241
-
International Classifications
-
Abstract
A spotting rifle barrel is aligned and retained relative to a launch tube and a spotting rifle receiver housing. A first annular lug is coupled to an outer portion of a breech end of the spotting rifle barrel. A second annular lug is coupled to an inner portion of the spotting rifle receiver housing. The spotting rifle barrel extends through the second annular lug so that a forward end of the first annular lug abuts an aft end of the second annular lug. The forward end of the first annular lug and the aft end of the second annular lug meet at a complementary radius of curvature. The first annular lug is retained in an abutting relationship with the second annular lug. A boresight adjustment assembly cooperates with a muzzle end of the spotting rifle barrel to adjust the boresight of the spotting rifle barrel while allowing for axial movement of the barrel.
Description
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of official duties by an employee of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon.
FIELD OF THE INVENTION
The invention relates generally to gun aiming devices, and more particularly to a system for aligning and retaining a spotting rifle barrel.
BACKGROUND OF THE INVENTION
Spotting rifles are used to determine range to a target. In general, the spotting rifle is set for a specific range and a tracer or burning round is fired to see if the selected range was accurate. If not, corrections are made until the correct range is achieved. Frequently, a spotting rifle is coupled to another launching device. That is, the spotting rifle is used to select the range for the launching device. Accordingly, it is desirable to align the boresight of the spotting rifle with that of the launching device. The advent of the ballistically matched spotting round has greatly reduced the difficulty and time required to align the spotting round impact with the launching device's round. However, it. is still necessary to accurately align the spotting rifle barrel with the launching device.
A preferred solution to this problem is to adjust the barrel of the spotting rifle without having to relocate the entire spotting rifle in relation to the main launch tube or rifle. One such spotting rifle barrel alignment mechanism is disclosed in U.S. Pat. No. 5,657,546 in which the breech end of the spotting rifle barrel floats in a seat where it engages the spotting rifle's receiver housing. The spotting rifle barrel is clamped at its muzzle end to a bracket depending from the muzzle of the launch tube. When a spotting round is fired, inertia of the round moving towards the muzzle end of the spotting rifle barrel tends to drive the spotting rifle barrel out of its floating breech end seat in the receiver housing. Once out of its breech end seat, the spotting rifle barrel tends to lose its boresight. Further, because the muzzle end of the spotting rifle barrel is clamped to the muzzle of the launch tube, the inertia of the round causes the launch tube to bow slightly as forces generated by the movement of the spotting rifle barrel are transferred to the muzzle of the launch tube. This is especially true when the launch tube is made from a material such as fiberglass.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a system that can align and retain a spotting rifle barrel.
Another object of the present invention is to provide a spotting rifle barrel alignment system that retains its boresight upon the firing of a spotting round.
Still another object of the present invention is to provide a spotting rifle barrel alignment and retaining system that prevents bowing of a launch tube to which the spotting rifle barrel is coupled.
Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings.
In accordance with the present invention, a system aligns and retains a spotting rifle barrel relative to a launch tube and a spotting rifle receiver housing. A first annular lug is coupled to an outer portion of a breech end of the spotting rifle barrel. A second annular lug is coupled to an inner portion of the spotting rifle receiver housing. The spotting rifle barrel extends through the second annular lug so that a forward end of the first annular lug abuts an aft end of the second annular lug. The forward end of the first annular lug and the aft end of the second annular lug meet at a complementary radius of curvature. Further, means are provided to retain the forward end of the first annular lug in an abutting relationship with the aft end of the second annular lug. A boresight adjustment assembly depends from a muzzle of the launch tube and contacts a muzzle end of the spotting rifle barrel. The boresight adjustment assembly adjusts the boresight of the spotting rifle barrel while allowing for axial movement relative thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a side view of a launching device with a spotting rifle coupled thereto in accordance with the present, invention;
FIG. 2
is a side cross-sectional view of a spotting rifle barrel and the aligning and retaining system of the present invention used to couple the spotting rifle barrel between the launching device's launch tube and receiver; and
FIG. 3
is a cross-section taken along line
3
—
3
in
FIG. 1
illustrating the boresight adjustment assembly of the present. invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to
FIG. 1
, a launching device is illustrated and referenced generally by numeral
100
. Launching device
100
includes a launch tube
102
from which a main round (not shown) is fired. Launch tube
102
serves as a mount for a spotting rifle
104
and a sight unit
106
. Spotting rifle
104
includes a spotting rifle barrel
104
A from which a spotting or tracer round (not shown) is fired, a receiver housing
104
B, and a boresight adjustment assembly
104
C. Spotting rifle barrel
104
A has its breech end supported in receiver housing
104
B. The muzzle end of spotting rifle barrel
104
A is supported by boresight adjustment assembly
104
C.
Referring now additionally to
FIG. 2
, the details of a system for aligning and retaining spotting rifle barrel
104
A relative to a (rocket) launch tube
102
and receiver housing
104
B are illustrated. For simplicity of illustration, launch tube
102
and receiver housing
104
B are shown only in their relevant portions. Specifically, the muzzle end of launch tube
102
and the forward end of receiver housing
104
B are illustrated.
Coupled to the breech end of spotting rifle barrel
104
A is an annular lug
10
. Annular lug
10
can be integral with spotting rifle barrel
104
A or could be threaded onto the breech end of spotting rifle barrel
104
A. If a threaded coupling is used, annular lug
10
can incorporate an annular seating flange
12
that will abut the breech end of spotting rifle barrel
104
A to assure proper positioning of annular lug
10
thereon. The forward end
14
of annular lug
10
is formed with a convex radius of curvature defined by a radius R
1
that originates from a point
16
located on the central longitudinal or boresight axis of spotting rifle barrel
104
A in proximity to the breech end of spotting rifle barrel
104
A. The exact location of point
16
is based on the position of boresight adjustment assembly
104
C as will be explained further below. To prevent rotation of spotting rifle barrel
104
A, a slot or notch
18
provided in annular lug
10
is engaged by a barrel position set screw
19
passing through receiver housing
104
B.
Coupled to an inner diameter of receiver housing
104
B is an annular lug
20
. Annular lug
20
can be integral with or threaded into receiver housing
104
B. If threaded into receiver housing
104
B, a set screw
22
passing through receiver housing
104
B can be used to engage annular lug
20
to hold it in position. Whether threaded into receiver housing
104
B or integrated therewith, the aft end
24
of annular lug
20
is formed with a concave radius of curvature complementary to the radius of curvature of forward end
14
of annular lug
10
. That is, radius R
1
also defines a concave radius of curvature of aft end
24
. Further, the inside diameter of annular lug
20
is less than the outside diameter of annular lug
10
. During assembly, spotting rifle barrel
104
A with annular lug
10
coupled thereto is inserted through receiver housing
10411
until forward end
14
of annular lug
10
abuts aft end
24
of annular lug
20
. Note that the complementary radius of curvature fit between forward end
14
and aft end
24
allows spotting rifle barrel
104
A to be pivoted smoothly about point
16
during boresight adjustment of spotting rifle barrel
104
A as will be explained further below.
To retain annular lug
10
and annular lug
20
in their abutting relationship, a variety of mechanisms can be used. In general, it is preferred that the retaining mechanism apply an axial force to spotting rifle barrel
104
so that annular lug
10
is pulled forward towards annular lug
20
. In this way, the force of retention is aligned with the inertia of the fired spotting or tracer round.
One such mechanism for applying and maintaining the necessary axial force will be described by way of example. The mechanism includes an annular extension
30
, a threaded ring
40
and, if needed, a lock nut
50
. Annular extension
30
is coupled (e.g., integrated with or attached to) receiver housing
104
B. Annular extension
30
is disposed about spotting rifle barrel
104
A with sufficient clearance to allow barrel
104
A to be pivoted about point
16
. The forward end
32
of annular extension
30
is formed with a convex radius of curvature defined by a radius R
2
that originates from point
16
. Threaded ring
40
is threaded onto spotting rifle barrel
104
A. The aft end
42
of threaded ring
40
has a concave radius of curvature complementary to that of forward end
32
. That is, radius R
2
also defines a concave radius of curvature of aft end
42
. Lock nut
50
is threaded onto spotting rifle barrel
104
A and is used to fix the position of threaded ring
40
.
Located at the muzzle end of spotting rifle barrel
104
A is boresight adjustment assembly
104
C which will be explained using
FIGS. 2 and 3
. Assembly
104
C includes a bracket
60
depending from the muzzle of launch tube
102
and a plurality of adjustment screw assemblies
62
,
64
and
66
. Bracket
60
serves as a housing through which the muzzle end of spotting rifle barrel
104
A passes. Adjustment screw assemblies
62
,
64
and
66
(e.g., each of which can include a corresponding locking helicoil
62
A,
64
A and
66
A set in bracket
60
with a corresponding set screw
62
B,
64
B and
66
B passing therethrough) are distributed about bracket
60
to align the boresight of spotting rifle barrel
104
A. Each set screw is positioned such that respective tips
62
C,
64
C and
66
C contact the outer portion of spotting rifle barrel
104
A as best seen in FIG.
3
. That is, the muzzle end of spotting rifle barrel
104
A is restrained from radial movement by assembly
104
C but is not restrained axially. In this way, spotting rifle barrel
104
A is free to expand or stretch axially without affecting the boresight of barrel
104
A and without transferring any axial forces to launch tube
102
which could cause bowing thereof. The use of locking helicoils
62
A,
64
A and
66
A prevents any movement of the corresponding set screw when the spotting rifle is fired.
In use, spotting rifle barrel
104
A is inserted through annular lug
20
and boresight adjustment assembly
104
C until annular lug
10
abuts annular lug
20
. Annular extension
30
, threaded ring
40
and lock nut
50
cooperate to apply and maintain an axial force that maintains the abutting relationship between annular lugs
10
and
20
. Set screw assemblies
62
,
64
and
66
are then adjusted as needed to change the boresight of spotting rifle barrel
104
A. The radius of curvature fit between annular lugs
10
and
20
, and annular extension
30
and threaded ring
40
, allow spotting rifle barrel
104
A to pivot about point
16
during the boresight adjustment thereof using adjustment screw assemblies
62
,
64
and
66
.
The location of pivot point
16
is determined by the plane at which adjustment screw assemblies
62
,
64
and
66
contact spotting rifle barrel
104
A. For example, in the illustrated. embodiment, the plane of contact defined by the adjustment screw assemblies (i.e., line
3
—
3
in
FIG. 2
) is aft of the muzzle opening of spotting rifle
104
A. Accordingly, point
16
will be aft of the breech opening of spotting rifle barrel
104
A.
The advantages of the present invention are numerous. A spotting rifle barrel is aligned and retained in alignment during the firing of a spotting round. Launch tube integrity is maintained as the inertia of the spotting round is not transferred to the launch tube since the spotting rifle barrel is only restrained axially at its breech end.
Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light of the above teachings. For example, annular extension
30
could be integral with receiver housing
104
B or incorporated as part of annular lug
20
. Further, as mentioned above, annular lug
10
could be integral with spotting rifle barrel
104
A and annular lug
20
could be integral with receiver housing
104
B. Note that if annular lug
20
is integral with receiver housing
104
B, set screw
22
is not needed. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described.
Claims
- 1. A system cooperating with a launch tube and a spotting rifle receiver housing for aligning and retaining a spotting rifle barrel, said system comprising:a first annular lug coupled to an outer portion of a breech end of a spotting rifle barrel; a second annular lug coupled to an inner portion of a spotting rifle receiver housing, wherein the spotting rifle barrel extends through said second annular lug and wherein a forward end of said first annular lug abuts an aft end of said second annular lug, and wherein said forward end of said first annular lug is convex and said aft end of said second annular lug is concave; means for retaining said forward end of said first annular lug in an abutting relationship with said aft end of said second annular lug; and means depending from a muzzle of a launch tube and contacting a muzzle end of the spotting rifle barrel for adjusting the boresight of the spotting rifle barrel.
- 2. A system as in claim 1 wherein said second annular lug is fixed in position, and wherein said means for retaining comprises means for applying an axial force to the spotting rifle barrel forward of said second annular lug, wherein said forward end of said first annular lug is pulled up against said aft end of said second annular lug.
- 3. A system as in claim 1 wherein said means for adjusting the boresight of the spotting rifle barrel comprises:a housing depending from the muzzle of the launch tube, said housing providing for the passage therethrough of the muzzle end of the spotting rifle barrel; and a plurality of adjustment screws passing through'said housing and distributed about the spotting rifle barrel, wherein each of said plurality of adjustment screws contacts an outer portion of the spotting rifle barrel.
- 4. A system as in claim 3 wherein said plurality of adjustment screws comprises three adjustment screws.
- 5. A system as in claim 1 wherein said first annular lug is integral with the breech end of the spotting rifle barrel.
- 6. A system as in claim 1 wherein said second annular lug is integral with the spotting rifle receiver housing.
- 7. A system as in claim 1 further comprising means for preventing rotation of the spotting rifle barrel about the central longitudinal axis thereof.
- 8. A system cooperating with a launch tube and a spotting rifle receiver housing for aligning and retaining a spotting rifle barrel, said system comprising:a first annular lug coupled to an outer portion of a breech end of a spotting rifle barrel, said first annular lug defining an outside diameter; a second annular lug coupled to an inner portion of a spotting rifle receiver housing, said second annular lug defining an inside diameter that is less than said outside diameter of said first annular lug, wherein the spotting rifle barrel extends through said second annular lug until a forward end of said first annular lug abuts an aft end of said second annular lug; an annular extension coupled to and extending from the receiver housing, said annular extension disposed about the spotting rifle barrel forward of said second annular lug; a threaded ring threadably engaging the outer portion of the spotting rifle barrel forward of said annular extension, wherein said threaded ring screws up against said annular extension and causes an axial force to be applied to the spotting rifle barrel wherein said forward end of said first annular lug is pulled up against said aft end of said second annular lug; a housing depending from the muzzle of the launch tube, said housing providing for the passage therethrough of the muzzle end of the spotting rifle barrel; and a plurality of adjustment screws passing through said housing and distributed about the spotting rifle barrel, wherein each of said plurality of adjustment screws is adjustably positioned to contact an outer portion of the spotting rifle barrel for adjusting the boresight of the spotting rifle barrel.
- 9. A system as in claim 8 wherein said forward end of said first annular lug and said aft end of said second annular lug meet at a complementary first radius of curvature.
- 10. A system as in claim 9 wherein said first radius of curvature is defined by a radius that originates from a point that is on the central longitudinal axis of the spotting rifle barrel and in proximity to the breech end of the spotting rifle barrel.
- 11. A system as in claim 10 wherein said retaining ring and said threaded ring meet am complementary second radius of curvature.
- 12. A system as in claim 11 wherein said second radius of curvature is defined by a radius that originates from said point.
- 13. A system as in claim 8 further comprising a lock nut threadably engaging the spotting rifle barrel forward of said threaded ring to maintain the position of said threaded ring.
- 14. A system as in claim 8 wherein said plurality of adjustment screws comprises three adjustment screws.
- 15. A system as in claim 8 wherein said first annular lug is integral with the breech end of the spotting rifle barrel.
- 16. A system as in claim 8 wherein said second annular lug is integral with the spotting rifle receiver housing.
- 17. A system as in claim 8 further comprising a set screw passing through the spotting rifle receiver housing and partially into said first annular lug for preventing rotation of the spotting rifle barrel about the central longitudinal axis thereof.
- 18. A system cooperating with a launch tube and a spotting rifle receiver housing for aligning and retaining a spotting rifle barrel, said system comprising:a first annular lug coupled to an outer portion of a breech end of a spotting rifle barrel; a second annular lug coupled to an inner portion of a spotting rifle receiver housing, wherein the spotting rifle barrel extends through said second annular lug and wherein a forward end of said first annular lug abuts an aft end of said second annular lug, and wherein said forward end of said first annular lug and said aft end of said second annular lug meet at a complementary radius of curvature; means for retaining said forward end of said first annular lug in an abutting relationship with said aft end of said second annular lug; and means depending from a muzzle of a launch tube and contacting a muzzle end of the spotting rifle barrel for adjusting the boresight of the spotting rifle barrel.
- 19. A system as in claim 18 wherein said radius of curvature is defined by a radius that originates from a point in proximity to the breech end of the spotting rifle barrel.
- 20. A system as in claim 18 wherein said second annular lug is fixed in position, and wherein said means for retaining comprises means for applying an axial force to the spotting rifle barrel forward of said second annular lug, wherein said forward end of said first annular lug is pulled up against said aft end of said second annular lug.
- 21. A system as in claim 18 wherein said means for adjusting the boresight of the spotting rifle barrel comprises:a housing depending from the muzzle of the launch tube, said housing providing for the passage therethrough of the muzzle end of the spotting rifle barrel; and a plurality of adjustment screws passing through said housing and distributed about the spotting rifle barrel, wherein each of said plurality of adjustment screws contacts an outer portion of the spotting rifle barrel.
- 22. A system as in claim 21 wherein said plurality of adjustment screws comprises three adjustment screws.
- 23. A system as in claim 18 wherein said first annular lug is integral with the breech end of the spotting rifle barrel.
- 24. A system as in claim 18 wherein said second annular lug is integral with the spotting rifle receiver housing.
- 25. A system as in claim 18 further comprising means for preventing rotation of the spotting rifle barrel about the central longitudinal axis thereof.
- 26. A system cooperating with a launch tube and a spotting rifle receiver housing for aligning and retaining a spotting rifle barrel, said system comprising:a first annular lug integral with an outer portion of a breech end of a spotting rifle barrel; a second annular lug coupled to an inner portion of a spotting rifle receiver housing, wherein the spotting rifle barrel extends through said second annular lug and wherein a forward end of said first annular lug abuts an aft end of said second annular lug; means for retaining said forward end of said first annular lug in an abutting relationship with said aft end of said second annular lug; and means depending from a muzzle of a launch tube and contacting a muzzle end of the spotting rifle barrel for adjusting the boresight of the spotting rifle barrel.
- 27. A system as in claim 26 wherein said forward end of said first annular lug is convex and said aft end of said second annular lug is concave.
- 28. A system as in claim 26 wherein said forward end of said first annular lug and said aft end of said second annular lug meet at a complementary radius of curvature.
- 29. A system as in claim 28 wherein said radius of curvature is defined by a radius that originates from a point in proximity to the breech end of the spotting rifle barrel.
- 30. A system as in claim 26 wherein said second annular lug is fixed in position, and wherein said means for retaining comprises means for applying an axial force to the spotting rifle barrel forward of said second annular lug, wherein said forward end of said first annular lug is pulled up against said aft end of said second annular lug.
- 31. A system as in claim 26 wherein said means for adjusting the boresight of the spotting rifle barrel comprises:a housing depending from the muzzle of the launch tube, said housing providing for the passage therethrough of the muzzle end of the spotting rifle barrel; and a plurality of adjustment screws passing through said housing and distributed about the spotting rifle barrel, wherein each of said plurality of adjustment screws contacts an outer portion of the spotting rifle barrel.
- 32. A system as in claim 31 wherein said plurality of adjustment screws comprises three adjustment screws.
- 33. A system as in claim 26 wherein said second annular lug is integral with the spotting rifle receiver housing.
- 34. A system as in claim 26 further comprising means for preventing rotation of the spotting rifle barrel about the central longitudinal axis thereof.
US Referenced Citations (17)