U.S. patent number 3,842,527 [Application Number 05/421,194] was granted by the patent office on 1974-10-22 for firearm with exchangeable barrels.
Invention is credited to Garth R. Low.
United States Patent |
3,842,527 |
Low |
October 22, 1974 |
FIREARM WITH EXCHANGEABLE BARRELS
Abstract
A firearm in the nature of a rifle with a plurality of
exchangeable barrels, any one barrel being adapted to be threadedly
connected to the receiver of the action. Thus, barrel replacement
is accomplished by retraction of a set screw and unthreading of one
barrel from the receiver and, thereafter, threading of a second
barrel in its place and tightening of the set screw, once proper
receiver-barrel alignment is achieved. Barrel exchange is
accommodated by a depressible stock insert which yields to
dimensional variations of each barrel during barrel removal and
replacement. A wrench-receiving counterbore at the distal end of
each barrel permits suitable tightening of each barrel prior to
firing. Barrel alignment is achieved by use of alignment markings
on the distal end of the receiver and the proximal end of each
barrel.
Inventors: |
Low; Garth R. (Midvale,
UT) |
Family
ID: |
23669552 |
Appl.
No.: |
05/421,194 |
Filed: |
December 3, 1973 |
Current U.S.
Class: |
42/75.02;
42/76.01 |
Current CPC
Class: |
F41A
21/482 (20130101); F41C 23/00 (20130101) |
Current International
Class: |
F41A
21/48 (20060101); F41A 21/00 (20060101); F41C
23/00 (20060101); F41c 021/00 (); F41c
023/00 () |
Field of
Search: |
;42/75B,77,76R,71R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Borchelt; Benjamin A.
Assistant Examiner: Jordan; C. T.
Attorney, Agent or Firm: Foster; Lynn G.
Claims
What is claimed and desired to be secured by United States Letters
Patent is:
1. A firearm comprising:
stock means;
means mounted to the stock means for receiving and firing a
cartridge, including trigger means, said mounted means comprising
an axial threaded bore at the distal end thereof;
removable and exchangeable barrel means having an axial reduced
diameter threaded proximal end, sized and shaped to be matingly
connected to the mounting means by the threads of the bore at the
distal end thereof, the stock means comprising recess means
supporting the barrel means adjacent said threaded connection, at
least a portion of the barrel means being exteriorly forwardly
convergently tapered and supported by the recess means of the stock
means;
said stock means further comprising a biased depressible section
defining at least part of the recess means and depressible
respecting the remainder of the stock means to permit axial
movement of the barrel means to accommodate said tapered exterior
barrel means surface during removal and connection of the barrel
means to the mounted means.
2. The firearm of claim 1 wherein the distal end of the mounted
means comprises a threaded bore oriented essentially normal to the
axis thereof and further comprising set screw means removably
threaded into said normal threaded bore and extending to the root
of spaced threads at the proximal end of the barrel means.
3. The firearm of claim 1 further comprising juxtaposed alignment
marks respectively carried by the barrel means and the distal end
of the mounted means to insure alignment therebetween.
4. The firearm of claim 1 wherein the biased depressible stock
section comprises an insert disposed within a correspondingly
shaped cavity of the remainder of the stock means and resilient
means with memory interposed between the base of the insert and the
base of the cavity urging the insert against the barrel means at
the recess means thereof but permitting depression of the insert
during axial barrel means displacement.
5. A firearm comprising:
stock means;
means mounted to the stock means for receiving and firing a
cartridge, including trigger means, said mounted means comprising
an axial threaded bore at the distal end thereof;
movable and exchangeable barrel means having an axial reduced
diameter threaded proximal end, sized to be matingly connected to
the mounted means by threads of the bore at the distal end thereof,
the stock means comprising recess means supporting the barrel means
adjacent said threaded connection;
said barrel means comprising a wrench-receiving female counterbore
exposed at the distal end of the barrel means in axial alignment
with and larger in transverse size than the bore of the barrel
means, whereby the barrel means may be loosened and tightened in
respect to the mounted means by using a wrench in the female
counterbore.
6. The firearm of claim 5 wherein the female counterbore is
polygonal in configuration.
7. A method of assembling a barrel to a receiver carried by a
stock, comprising the steps of:
advancing a separate barrel generally along its axis toward a
receiver carried by a stock;
depressing an insert of the stock counter to predetermined bias by
a diametrally enlarged proximal end portion of the barrel;
threadedly connecting the proximal end of the barrel to the distal
end of the receiver; and
tightening the threaded connection by placing a male wrench in a
female wrench-receiving counterbore disposed along the axis of the
barrel and exposed at the distal end of the barrel, and rotating
the wrench and barrel.
Description
BACKGROUND
1. Field of Invention
The present invention relates generally to firearms and more
particularly to a firearm with a plurality of exchangeable
barrels.
2. Prior Art
Prior proposals for use of a single stock and action together with
multiple barrels or any one of several removable barrels have been
extensive, inconvenient to accomplish barrel exchange, resulted in
damage to the exterior of removable barrels, involved complex
mechanisms for barrel exchange and have lacked eye appeal, bearing
at best little relationship to the appearance of conventional
firearms.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
The present invention provides a firearm with exchangeable barrels,
each barrel being removably threaded into the action and there
anchored in correct alignment. Tightening is accomplished using a
male wrench in a correspondingly configurated counterbore at the
distal end of each barrel. A depressible stock insert permits
barrel displacement during exchange.
It is a primary object of the present invention to provide an
improved firearm.
It is another paramount object of the present invention to provide
a novel firearm in connection with which any one of several
exchangeable barrels may be utilized.
It is another important object of the present invention to provide
a novel firearm utilizing a removable barrel threaded to the action
and removably anchored in proper alignment.
Another significant object of the present invention is the
provision of a novel firearm the barrel of which is removable and
tightened in place using a male wrench in a correspondingly
configurated counterbore at the distal end of the barrel.
Another and no less important object of the present invention is
the provision of an improved firearm with a removable barrel,
barrel removal being accommodated by a depressible stock
insert.
These and other objects and features of the present invention will
be apparent from the following detailed description, taken with
reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective of one presently preferred firearm
embodiment, in the form of a rifle, according to the present
invention;
FIG. 2 is an exploded fragmentary enlarged perspective of the
firearm of FIG. 1;
FIG. 3 is an end view taken along line 3--3 of FIG. 1;
FIG. 4 is a cross sectional view taken along line 4--4 of FIG. 1;
and
FIG. 5 is a fragmentary view showing the threaded connection
between the barrel and the receiver of the action.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT
While it is to be appreciated that the present invention has
application in a broad range of firearms, the Figures illustrate a
rifle embodiment generally designated 10. Except as hereinafter
explained, the rifle 10 comprises a conventional stock 12 equipped
with a shoulder plate 14 and a barrel cradle recess 16. The stock
12 is also equipped with a generally rectangular cavity 18 opening
centrally at the top of the stock rearward of the cradle recess 16
and forward of the bolt action recess 20 of the stock. The recess
20 in a conventional way receives action 22, which includes a bolt
24 equipped with a handle 26. The bolt 24 is equipped with an
ejector 28 and would normally conceal a magazine (not shown)
extending downward into the stock at the action recess 20. A
trigger 30 conventionally projects out of the bottom of the stock
and is sheltered by a trigger guard 32, both in a conventional
manner. The action 22, trigger 30 and trigger guard 32 are retained
in the indicated position in a conventional manner using screws and
the like. The rear collar 34 of the receiver 36 is shown as having
a peep sight 38 conventionally mounted thereon, although it is to
be appreciated that any type of sight, including a telescope may be
appropriately associated with the rifle 10. The forward collar 40
comprises a threaded side bore 42, into which a set screw 44 is
appropriately placed for purposes and in a manner hereinafter more
fully described. The forward collar 40 of the receiver 36 also
includes an alignment mark 46 by which the yet to be described
barrel is properly positioned once connected to the receiver.
The cavity 18 of the stock 12, as best seen in FIG. 4 comprises an
essentially horizontal base surface 50 and spaced parallel vertical
side wall interior surfaces 52 each comprising part of a side wall
54 of the stock 12. The base 50 comprises two blind bores 56 having
a central conical recess 58. Each conical recess 58 receives one
axially directed pointed end 60 of two compression springs 62, the
springs 62 being sized and shaped so that the coils diametrally fit
within recess 58.
The two springs 62 comprise part of a barrel
displacement-accommodating stock insert assembly 64. The assembly
comprises insert 66, the side edges 68 being spaced a distance
slightly greater than the spacing between the wall surfaces 52 and
parallel one to another but each perpendicular to the base 69 of
the insert 66. The insert 66 also comprises a forwardly convergent
rounded and tapered barrel cradling recess 72. The base surface 69
is shaped at two locations with annular recesses 74 into which the
top coiled end of one spring 62 rests. Thus, once the barrel is
assembled to the receiver, the insert 66 assumes the position
illustrated in FIG. 4. However, to accommodate barrel removal, the
insert 66 may be depressed counter to the force of compression
springs 62 in a manner hereinafter more fully described.
The rifle 10 comprises an exchangeable barrel 80, which may be
replaced by any one of several additional barrels, the plurality of
barrels being of various calibers, depending upon availability and
the wishes of the purchaser. The barrel 80 comprises a conventional
lining 82 defining a conventional bullet projecting bore and an
enlarged exposed proximal end portion 84. The proximal end portion
84 terminates in threads 86 of a reduced diameter, which are
threadedly joined to threads 88 (FIG. 5) of the collar 40, at the
interior surface thereof. An alignment mark 90 at the proximal
portion 84 is formed, after the unit has been manufactured and
tested, directly adjacent the previously mentioned alignment mark
46 so that the lay user may disassemble and reassemble the rifle 10
using one or more exchangeable barrels 80, without disturbing the
accuracy of projectiles issuing from each barrel 80.
The exterior of the barrel 80 is sharply tapered at 92, which in
the assembled condition rests within the forwardly convergent
recess 72 of the stock insert 66. The barrel 80 also comprises an
elongated central portion 94, which is also tapered but to a lesser
degree than taper 92. The distal end 96 of the barrel 80 is shown
as having a front sight 98 appropriately and conventionally mounted
thereto. The bore lining 82 terminates a short distance, preferably
on the order of less than one inch, from the terminal face 100 at
the distal end 96. A polygonal counterbore 102 is disposed forward
of the distal terminal site of the lining 82, as best shown in FIG.
3, and is adapted to receive a similarly shaped wrench,
accommodating tightening of a barrel 80 being assembled to the
rifle 10, to facilitate a tight threaded connection at 86-88 and to
cause alignment marks 46 and 90 to be placed side by side as
illustrated in FIG. 1, or loosening of a barrel 80 being removed
from the rifle 10. Clearly, by utilization of the wrench
counterbore 102 and a correspondingly shaped wrench, damage to the
barrel is minimized and any scoring or the like which occurs is
concealed from the human eye within the counterbore 102. The rifle
10, independent of the caliber of any barrel 80 associated
therewith appears to the eye to be essentially a conventional
firearm, any barrel 80 being secured in the assembled condition
using the set screw 44 properly advanced in the threaded bore 42 of
the collar 40 such that, with the alignment marks 46 and 90 as
shown in FIG. 1, the interior tapered end 104 of the set screw 44
seats within a root 106 of threads 86.
The use of the rifle 10 is conventional and need not here be
described. However, when the user desires to change from a barrel
80 of one caliber to a barrel 80 of another caliber, a screw driver
or Allen wrench is placed within a slot or recess at the exposed
face of the set screw 44 and the set screw is withdrawn along the
threaded bore 42 until the tapered tip 104 clears the threads 86. A
wrench is non-rotatably fitted within the wrench counterbore 102 at
the distal end 96 of the barrel 80 being removed. The wrench is
rotated in a clockwise direction as viewed in FIG. 1 causing the
threads 86 to move forward in respect to the threads 88. After the
threaded connection 86-88 is initially loosened, the rotation may
be continued by hand until the threads 86 of the barrel 80 clear
the receiver threads 88. As the barrel 80 being removed is advanced
within the threads 88, the stock insert 66 is depressed by reason
of engagement with the barrel taper 92, thereby accommodating the
withdrawal. Once the withdrawal has been completed, the springs 62
return the insert 66 to its extended position illustrated in FIG.
4. An additional barrel 80 may then be assembled to the remainder
of the rifle 10 by repeating the indicated steps in reverse.
The invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof. The
present embodiment is therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being
indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are therefore intended to be
embraced therein.
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