U.S. patent number 3,731,418 [Application Number 05/126,441] was granted by the patent office on 1973-05-08 for small firearms with exchangeable barrel.
This patent grant is currently assigned to J. P. Sauer & Sohn GmbH. Invention is credited to Manfred Birkenaen, Manfred Birkenhagen.
United States Patent |
3,731,418 |
Birkenhagen , et
al. |
May 8, 1973 |
SMALL FIREARMS WITH EXCHANGEABLE BARREL
Abstract
An apparatus for detachably securing a firearm barrel with a
receiver flange of a receiver assembly and characterized in that
the receiver flange is longitudinally slit so as to permit the
flange to be circumferentially constricted into clamping engagement
with the barrel.
Inventors: |
Birkenhagen; Manfred
(Eckernforde, DT), Birkenaen; Manfred (Eckernforde,
DT) |
Assignee: |
J. P. Sauer & Sohn GmbH
(Eckernforde, DT)
|
Family
ID: |
5789092 |
Appl.
No.: |
05/126,441 |
Filed: |
March 22, 1971 |
Foreign Application Priority Data
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Nov 25, 1970 [DT] |
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P 20 57 995.7 |
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Current U.S.
Class: |
42/75.02 |
Current CPC
Class: |
F41A
21/481 (20130101); F41A 21/482 (20130101); F41A
21/487 (20130101) |
Current International
Class: |
F41A
21/48 (20060101); F41A 21/00 (20060101); F41c
021/00 (); F41c 023/00 () |
Field of
Search: |
;42/75B,75A,77,75B,75A,77 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1,167,702 |
|
Apr 1964 |
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DT |
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418,756 |
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Oct 1934 |
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GB |
|
Primary Examiner: Borchelt; Benjamin A.
Assistant Examiner: Jordan; C. T.
Claims
What is claimed is:
1. A firearm including exchangeable barrel means and
comprising:
receiver flange means including
barrel receiving socket means for receiving a terminal end portion
of said barrel means,
support means disposed generally beneath said socket means, and
longitudinal slit means formed in said support means and operable
to permit circumferential contraction of said barrel receiving
socket means;
said support means being operable to be connected with firearm
stock means; and
clamping means carried by said support means and operable to
engage said flange means on opposite sides of said slit means,
induce convergence of said opposite sides of said slit means,
and
cause circumferential contraction of said barrel receiving socket
means of said flange means.
2. A firearm as described in claim 1 further including:
restraining means engaging outermost portions of said opposite
sides of said slit means,
said restraining means being operable to restrain convergence of
said outermost portions of said opposite sides of said slit means
and thereby cause said clamping means to induce convergence of
inner portions of said sides of said slit means so as to produce
circumferential contraction of said barrel receiving socket means
without imposing substantial barrel flattening forces on barrel
means received in said socket means.
3. A firearm as described in claim 2 wherein:
said restraining means comprises connecting means operable to
interconnect said support means with a firearm stock means; and
said restraining means further comprises screw means threadably
engaging said opposite sides of said slit means, with said screw
means extending along an axis which is generally perpendicular to a
longitudinal axis of said barrel means.
4. A firearm as described in claim 2 wherein:
said slit means has a generally T-shaped cross sectional
configuration, extending transversely of the longitudinal axis of
said barrel means; and
said restraining means comprises:
block means having a generally T-shaped cross section slidably
disposed in said slit means for sliding movement longitudinally of
said barrel means, and
threaded securing means threadably mounted in said block means and
operable to abuttingly engage generally downwardly facing surfaces
of said slit means.
5. A firearm as described in claim 1 further including:
first, aligning recess means formed on the outer periphery of said
barrel means;
second, aligning recess means formed in said support means;
alignment securing means operable to extend through each of said
first and second recess means and thereby secure said barrel means
in a predetermined position relative to said flange means;
block means slidably carried by said support means; and
restraining means carried by said block means and operable to
abuttingly engage and secure said alignment securing means in said
first and second recess means.
6. A firearm as described in claim 1 further comprising:
bayonet-type locking lug means detachably interconnecting said
barrel means and said flange means; and
stop means carried by said flange means and operable to maintain
said bayonet-type locking lug means in a barrel means securing
position.
7. A firearm as described in claim 1 further comprising:
first threaded surface means carried by said flange means; and
second threaded surface means carried by said barrel means and
operable to threadably engage said first threaded surface
means;
said clamping means being operable to intersect said threadably
engaged first and second threaded surface means and thereby
maintain said first and second threaded surface means in a
predetermined axial relationship.
8. A firearm as described in claim 1 wherein said clamping means
comprises:
lever means pivotally connected with said receiver flange
means;
rotary cam means carried by said lever means; and
cam follower means carried by constrictable portions of said
support means disposed laterally adjacent said slit means;
said cam means of said lever means being operable to cammingly
cooperate with said cam follower means to induce barrel means
clamping constriction of said barrel receiving socket means in
response to pivotal movement of said lever means toward said barrel
means.
9. A firearm as described in claim 8 wherein:
said lever means comprises:
mounting eyes disposed on opposite lateral sides of said support
means;
said clamping means comprises bolt means transversely intersecting
said slit means and providing rotatable support for said eye means;
and
said rotary cam means comprises a pair of rotary cams each
supported by one of said eye means.
10. A firearm as described in claim 9 wherein said rotary cam means
comprises a pair of generally helical cam surface means disposed on
opposite sides of said support means and generally facing said slit
means.
11. A firearm as described in claim 10 wherein:
said slit means has a generally T-shaped cross sectional
configuration, extending transversely of the longitudinal axis of
said barrel means; and
restraining means being carried by said support means and
comprising:
block means having a generally T-shaped cross section slidably
disposed in said slit means for sliding movement longitudinally of
said barrel means, and
threaded securing means threadably mounted in said block means and
operable to abuttingly engage generally downwardly facing surfaces
of said slit means.
12. A firearm according to claim 1 wherein said receiver flange
means further includes:
means, in addition to said clamping means, for resisting axial
displacement of said barrel means from said socket means.
Description
GENERAL BACKGROUND, OBJECTS, AND
SUMMARY OF INVENTION
The invention relates to a gun with exchangeable barrel and in
which the barrel rear end is inserted releasably in a corresponding
recess of a receiver flange with an axial stop.
Customarily the barrel and the casing, or receiver, of small arms,
especially guns, are connected with each other by means of a
self-locking attaching thread. Since this connection must be very
tight because it influences the performance of the firearm, it is
not possible by simple means to exchange the barrel of the firearm
without there being the necessity afterwards of "reworking" the
firearm and "zeroing it in" again.
A construction has been known where basically the exchange of the
barrel with simple means is possible without subsequent reworking,
whereby, however, the receiver flange, screwed tightly with the
barrel, is separate from the remaining body of the receiver. In
that case, however, the barrel is screwed together with the
receiver and stock by means of two screws, as a result of which the
vibrations of the barrel developing during cartridge detonation
will be prevented from spreading freely. According to experience,
however, the pre-supposition for good performance and for a
constant alignment entails a freely vibrating or unrestrained
barrel.
The present invention is based on the object of producing a gun
with an exchangeable barrel, where the exchange of the barrel is
possible with the help of a simple tool without special auxiliary
devices. Under certain circumstances, it is possible, without any
tool, to effect such an exchange. Beyond this, no reworking is
necessary after the exchange and, further-more, the performance of
the gun and the future position of the firearm will not be
influenced disadvantageously. Further, this invention recognizes
that one must avoid an arrangement wherein, because of a connection
between the barrel and the front part of the stock via a second
attaching screw, the working of the wood of the front part of the
stock could have an adverse effect on the future position of the
firearm.
According to the invention this problem is solved, in the case of a
gun of the above mentioned type, by the fact that the receiver
flange has a longitudinal slit in its bottom side, developed in a
reinforced manner as a support and facing the stock, and that
tightening elements will tighten the sides releasably facing each
other along the longitudinal slit.
Therefore, a gun has been produced where the barrel can be quickly
exchanged for another one with a different caliber and which also
can be quickly and simply disassembled for the purpose of
transportation. In this way a requirement will be met which in the
case of drop barrel guns has been satisfactory for decades but,
which in the case of repeater rifles, however, has not been
satisfactory heretofore because of a different type of
con-struction. The gunner will now be able to shoot with his gun
shells of different calibers. He does not need to become accustomed
therefore to other dimensions of the stock all over again and will
not be influenced as a result in a disadvantageous manner in regard
to his shooting skill.
Moreover, it is less expensive to procure exchangeable barrels
merely for various calibers than it is to procure entirely new
repeater rifles. The characterizing tightening connection between
the receiver and the barrel is also tight enough to be able to
safely absorb the loads or stresses occurring during the cartridge
detonation, including the vibrations which substantially influence
performance.
It has, therefore, become possible to produce a quickly and simply
exchangeable barrel while maintaining a freely vibrating attachment
mode.
To this must be added, moreover, that the forces produced by the
tightening will create a negative pre-tension or compression at the
breech end of the barrel, that is in the cartridge chamber. This
negative pre-tension acts counter to the forces occurring during
the development of the shot, i.e., cartridge detonation. Therefore,
the outside dimensions of a repeater gun of the type according to
the invention, need not be any larger than those of known repeater
guns. The firearm thus remains light and handy just like
traditional firearms.
Preferably in the lower section of the longitudinal receiver flange
slit, removed from the barrel recess or socket, there is a support
acting as a counter support for the flange tightening elements.
According to one embodiment, presented by way of example, this
support or restraining means may be constituted by a screw
connecting the stock with a receiver flange, which screw is screwed
into a thread in the longitudinal slit. This restraining means,
however, can also be a T-shaped sliding block into which the screw
connecting the stock with the support has been screwed. In this
case, the sliding block pulls the support onto the stock.
In the case of this embodiment, by way of example, it will be
advantageous to provide a recess or blind hole in the barrel, on
the periphery of the cylindrical end of the barrel which is
inserted into the receiver flange. A cylindrical peg is inserted
into this recess and a recess passing through the longitudinal
slit. This peg is supported on a carrying surface of the sliding
block. This results in the barrel being secured in axial and
peripheral directions although it is also held by the
tightening.
Moreover, the cylindrical peg makes certain that the barrel will
always be inserted in the same position in which it had been fitted
into the firearm.
The purpose of these different supports in the lower section of the
longitudinal slit is to avoid bending, or barrel flattening, forces
during the tightening of the tightening elements, so that merely
tangential forces will engage in the barrel at the place of
tightening.
Instead of securing the barrel by way of a loose cylindrical peg
and a slidable sliding block, it is also possible to provide a kind
of bayonet lock between the barrel and receiver flange, including
locking studs at the rear end of the barrel and corresponding
counter bearings or lugs at the base of the recess of the receiver
flange. With this construction, a positioning of the barrel which
will always be the same upon barrel insertion can be
guaranteed.
Another possible mode of attachment is by way of a thread, known
per se, at the end of the barrel and in the recess of the receiver
flange. However, this threaded joint does not need to be made as
difficult as most threads to operate because of the longitudinal
slit and the tightening elements. In order to achieve a firm
self-locking seat and, as a guarantee of the exact position of the
barrel after each barrel exchange process, the tightening elements,
developed as fitted bolts, tangentially intersect the threaded
joint. Thus, the barrel will be additionally prevented from
twisting.
A particularly favorable embodiment, by way of example, which
permits the exchange of the barrel without the assistance of any
kind of tool, has a front part of the stock separate from the main
stock. This fore-part can be flipped down by means of a tightening
lever. The receiver flange constricting means of the tightening
lever is constituted by cam surfaces which are provided on the
mounting eyes of the tightening lever. These cam surfaces act upon
corresponding cam follower surfaces of the clamping sleeves, which
follower surfaces are shiftable axially on means rotatably
supporting the lever so as to induce convergance of sides of the
receiver flange slit. At the same time and in order to avoid
asymmetry, the tightening lever effectively will be arranged
symmetrical in relation to the axis of the gun.
The lever supporting means may comprise a bolt provided on both
sides with knobs. On the shaft of this bolt, the bearing eyes of
the clamping lever are guided. These bearing eyes are supported by
the knobs of the bolts. The clamping sleeves are inserted on the
bolt between the cam means of the bearing eyes of the clamping
lever and the sides of the flange slit.
In this case, the cam or ramp surfaces may be oppositely oriented
threads or helical surfaces, whereby the tightened socket receiving
barrel will be loosened by flipping or pivoting down the front part
of the stock. After release of an additional safety, the barrel can
be pulled out of the socket in a forward direction.
DRAWINGS
The invention is to be explained once more in detail on the basis
of the embodiments given by way of example, so that from it all the
details, advantages and characteristics of the invention will
become clear.
FIG. 1 shows a first embodiment of the place of connection between
the exchanged barrel and the receiver of the gun according to the
invention by way of example in the form of a longitudinal
section;
FIG. 2 shows a section following line II--II in FIG. 1;
FIG. 3 shows a second embodiment with another type of attachment of
the barrel likewise in longitudinal section;
FIG. 4 shows a section according to line IV--IV in FIG. 3;
FIG. 5 is a presentation in longitudinal section of a third
embodiment of the gun according to the invention by way of
example;
FIG. 6 shows a section following line VI--VI in FIG. 5;
FIG. 7 shows a presentation in longitudinal section of a fourth
embodiment of the gun according to the invention by way of example,
with a pivotable front stock; and
FIG. 8 shows a cut following line VIII--VIII in FIG. 7.
DETAILED DESCRIPTION
The receiver 10 with breech bolt 11, firing pin 12 and firing pin
spring 13, as well as the exchangeable barrel 14, is common to all
embodiments given by way of example. All other parts of the firearm
which have no influence on the invention and on which the invention
does not exert any influence either, have been omitted for the sake
of simplicity. The inside of the barrel has been made in the
customary manner with a cartridge chamber 15 and a bore 16. All
embodiments have, in common, a slotted support disposed underneath
an annularly developed receiver flange.
The support slit has the purpose of tightening the receiver flange,
in response to the action of tightening elements which narrow the
slit, so that the end of barrel 14 introduced into the bore of the
receiver flange will be firmly tightened but can be easily pulled
out whenever the tightening elements are released. The axial and
circumferential dimensions of the tightening or constrictable
connection between the end of the barrel and the bore of the
receiver flange are selected such that the tightening or
constricting forces are large enough to absorb the axial forces
occurring as a result of the strain from a shot, without any
additional locking being required between the barrel and the
receiver.
First of all, we shall now describe the embodiment according to
FIGS. 1 and 2 presented by way of example.
The smooth cylindrical bore 21 of the receiver flange 20 has been
harmonized with a recessed end 22 of the barrel in such a way that
in the case of the receiver flange, when not tightened, provides a
telescoping, gliding fit seat for barred end 22. Upon insertion of
end 22 of the barrel into bore 21 of the receiver flange, the
abutment collar 23 on the barrel strikes against the front edge of
the receiver flange, before the end of the barrel itself reaches
the base of bore 21.
The barrel inserted this way into the receiver flange 20 is
tightened with the help of tightening screws 24, 25. These screws
lie with their heads sunk in corresponding bores of stop or flange
26. By way of their threaded shafts, these screws are screwed into
corresponding female threads 27 in the half of flange 26, which is
opposite the screw head. The support itself, as mentioned
previously, has been divided into two parts by a longitudinal slit
28, which is aligned with the central axis of the barrel end
receiving bore of generally cylindrical means 20. By the proper
tightening of screws 24 and 25, the clamping force of the receiver
flange on the end of the barrel can be made so great that the
barrel will be seated completely firmly in the receiver and the
connection can absorb all axial forces occurring upon detonation of
a cartridge.
In order to avoid the imposition of bending or travel flattening
forces on the receiver flange 20 as a result of the screw
tightening, there is a threaded bore 29 formed symmetrically in
each half of clamping flange means 26, and passing upwardly through
slot 28. A screw 30 is screwed into the lowest part of the slit via
bore 29 and thus partially into the side walls of the two halves of
the support 26, with which screw the receiver is screwed to the
stock. With the support provided by screw or restraining means 30,
which will prevent a compression of the slit by the tightening
screws 24 and 25, one will perceive that, in fact, only tangential
forces are imposed on barrel end 22 during tightening between the
receiver flange 20 and the end 22 of the barrel.
Even though the clamping forces of screws 24 and 25 will suffice to
hold the barrel 14 in the receiver 10, an axial safety will be
provided which becomes effective when, in actual fact, the
tightening mechanism has not been properly tightened. Accordingly,
there are circumferentially spaced lock studs 31 distributed over
the periphery of the end of the barrel which are rotatable to a
position behind corresponding projections 32 close to the base of
bore 21. Thus, the barrel, first of all, will be inserted in socket
20, twisted counter to its final position. It will then be turned
or twisted to its position of use, whereby lock studs 31 move
behind projections 32. In order to assure an unequivocal position
of the barrel after its rotation, a stop screw 33 has been
provided. This screw enters socket 20 from the outside and projects
into the path of the lock studs. Thus, upon twisting the barrel in
FIG. 2 in a clockwise direction, and up to the stop 33, the barrel
will then obtain its correct position in relation to the
receiver.
The embodiment according to FIGS. 3 and 4 show generally a similar
construction.
In this embodiment the offset (i.e., reduced) end 42 of the barrel
is likewise inserted into a receiver flange 40 up to the extent
permitted by engagement of a barrel abutment 43 with the end of the
socket 40, while tightening elements 44, 45 of the bipartite stop
46 are loosened. In this case, also, a screw 50, serving for the
attachment of the receiver to the stock of the gun, engages with
female threaded sides of slit 48 in order to exclude any barrel
bending or flattening forces during flange tightening.
In the present case, however, the prevention of axial movement
between the end 42 of the barrel and the receiver flange 40 is
accomplished by way of a threaded connection 41. However, and in
contrast to the known connections, and with loosened tightening
screws 44, 45, the barrel can easily be screwed into the receiver
flange 40.
As a matter of safety, and for the purpose of an unequivocal
fixation of the barrel in the receiver, the transverse bores for
the tightening screws 44 and 45 have been disposed in such a manner
that the screws, which have been developed partly with a
cylindrical shaft 51, intersect concave, cylindrical segment
recesses formed to extend transversely of the connecting thread 41.
As a result of this, the tightening screws 44, 45 can be inserted
and tightened only when the barrel has been screwed into a quite
definite axial position, namely the stop position, and into a quite
definite angular position, so as to align the thread recesses of
barrel 14 with the bores for screws 44, 45. Thus, even in the case
of loosening of the tightening screws 44 and 45, the barrel still
cannot be separated from the receiver due to the intersection of
screws 44, 45 with the transverse recesses of thread means 41.
A development similar to the one in the first design is shown by
the example according to FIGS. 5 and 6.
Here too there is a receiver flange 60 with a smooth inside bore
61. In this bore, an end 62 of the barrel 14 is inserted up to the
abutment of its collar 63 with the front edge of the receiver
flange 60.
A stop or flange means 66 is provided with a longitudinal, vertical
slit 68 and includes transverse bores for the reception of
tightening screws 64 and 65. These screws are disposed
approximately in the same position as in the example according to
FIGS. 1 and 2.
The safety, and axial as well as angular fixation of the barrel in
the receiver flange is accomplished in this case in a different
manner.
As FIG. 6 shows, the vertical flange means slit, in its lower
section, has a T-shaped enlargement 71 in which there is a
longitudinally slidable sliding block 72. This sliding block 72
serves, for one thing, the purpose of preventing the excessive
compression of slit 68 by the tightening screws, so that only
tangential forces can be imposed on the circumference of the barrel
due to the screw induced constriction of socket means 60. The
sliding block is fixed in an axial direction by means of attaching
screw means 70, with which the receiver is screwed onto the gun
stock.
Prior to tightening of the tightening screws 64, 65 and the
insertion of attaching screw 70, however, the restraining means or
sliding block is slidable in an axial direction in its T-shaped
slit. This permits a cylindrical pin 73 or alignment recurring
means to be slipped in, from below through second aligning recess
means or fitted bore in the flange means, into engagement with a
correspondingly fitted first aligning recess means or blind hole 74
in the cylindrical end of the barrel, and thus fix the barrel both
axially and in its angular position. With cylindrical pin 73
completely inserted, the sliding block 72, with its offset end or
restraining means 75, can be pushed along slit 71 to dispose its
offset end below the cylindrical pin so that the latter can no
longer glide out of its fitted bore means. The axial fixation of
sliding block 72 is then accomplished by means of attaching screw
70 being screwed into engagement with the portions of flange means
66 above block 72.
Thus the barrel has been exactly aligned in the receiver and,
moreover in the case of a possible loosening of the tightening
screws 64 and 65, it has been secured from dropping out.
Another solution again is shown by the embodiment in FIGS. 7 and
8.
End 82 of the barrel and receiver flange 80, inclusive of the
arrangement of the lock studs 91 and counter elements or
projections 92 in the bore, are the same as the corresponding
elements in the example described on the basis of FIGS. 1 and 2.
The support 86 too is provided with a vertical, longitudinal slit
88, which has in its lower portion, a T-shaped enlargement 93, as
known already from the embodiment according to FIG. 5. Slot
enlargement 93 receives a sliding block 94, into which a screw 95
is threadably disposed for the attachment of the stock and securing
of block 94.
In this case too, sliding block 94 serves to avoid the occurrence
of bending or barrel flattening forces during tightening of the
receiver flange. The tightening of the receiver flange, however, in
the case of the embodiment described here, is accomplished in a
particularly simple manner and is particularly practical for
operation during exchange of the barrel.
A cylindrical tightening bolt 97, provided with heads 96, passes
through a bore of support 86. A tightening lever 98, pointing
longitudinally forward, has been mounted with bearing eyes 99
journaled on the tightening bolt 97.
Discs 100 have been provided, each of which is rotatably slidably
supported on one side by a bolt head 96 and on the other side has a
screw-shaped ramp surface. A transverse bore 101 in the support 86
has been provided with a frusto-conical enlargement on both entry
ends. Clamping sleeves 102 fit in these enlargements and have
screw-shaped or helical cam follower surfaces corresponding to the
shapes of cam surfaces of the annular discs 100.
The annular discs 100 are rigidly connected with the bearing eyes
99 of the tightening lever. The effective distance between the
outer surfaces of the clamping sleeves 102, acted on by discs 100,
becomes smaller or larger depending on the position of the lever
upon pivoting of the clamping lever 98. The ramp surfaces are
dimensionally harmonized in such a way with regard to one another
that, in the case of being swung upwards, the effective distance
between the sides of the receiver as defined by sleeves 102 is the
smallest and, as a result of that, the support is clamped together.
The distance becomes larger when the lever 98 is pivoted downwards.
At the same time, of course, the clamping connection between the
receiver flange 80 and end 82 of the barrel is loosened.
In this embodiment the fore-stock of the gun is subdivided into the
fixed part 103 and a front part 104 that can be let down. Part 104
is connected by means of an attaching screw 105 with the clamping
lever 98. However, there is no connectin between the front part of
the stock and the barrel.
The operation, in the case of exchanging barrels, is as
follows.
The front part 104 of stock is pivoted or swung down, together with
clamping lever 98. During this time, annular discs 100 are rotated
in relation to the clamping sleeves 102 and the clamping force
exerted on these sleeves and transmitted to the support declines.
Now the barrel can be twisted from its bayonet lock 91, 92 and can
be pulled out from the cylindrical bore of the receiver flange 80.
After insertion of another barrel, with for example a different
caliber, which is put into the inserting positon with the same
bayonet catch, the front part of stock 104 may be pushed up again.
As a result, the clamping sleeves 102 are again compressed by the
camming cooperation between elements 100 and 102 and a clamping
force is exerted by the support on receiver flange 80. Therefore,
with this embodiment, it is particularly easy to carry out an
exchange of the barrel.
To this advantageous development which makes possible a
particularly quick and simple exchange of the gun barrels, it must
be added that, as a result of the negative pre-tension or
compression exerted by the clamping forces of the receiver flange
at the end of the barrel, there will be a relieving counter effect
operable to offset the radial forces occurring during firing of the
shot. Thus, it will not be necessary to construct the entire
arrangement, for reasons of strength, with more expensive material
than that which is used in the case of known guns with exchangeable
barrels.
SUMMARY OF MAJOR ADVANTAGES AND
GENERAL SCOPE OF INVENTION
A principal advantage of the invention resides in the provision of
a uniquely simplified barrel clamping arrangement which facilitates
barrel exchange and minimizes or eliminates the necessity for
repeated "zeroing-in".
Another advantage of the invention relates to the particular
circumferential clamping arrangement which is operable to impose
tangentially directed barrel end securing forces, without inducing
barrel flattening or distortion.
The embodiment of the apparatus which is characterized by a lever
actuated clamping device provides a uniquely simplified and
reliable arrangement permitting an exchange of gun barrels without
requiring recourse to special tools or equipment or an increase in
size or weight of gun components.
Those familiar with this disclosure and skilled in the firearms art
may recognize additions, deletions, substitutions or modifications
which would fall within the purview of the invention as set forth
in the appended claims.
* * * * *