U.S. patent application number 09/775090 was filed with the patent office on 2002-11-07 for combination barrel adjustment and magazine cutoff for a takedown firearm.
Invention is credited to Clay, David Richard.
Application Number | 20020162266 09/775090 |
Document ID | / |
Family ID | 25103300 |
Filed Date | 2002-11-07 |
United States Patent
Application |
20020162266 |
Kind Code |
A1 |
Clay, David Richard |
November 7, 2002 |
COMBINATION BARREL ADJUSTMENT AND MAGAZINE CUTOFF FOR A TAKEDOWN
FIREARM
Abstract
A flex-plate adapter for a takedown firearm has front and rear
sections. The rear section includes adjustment screws to change the
gap between the front and rear sections. Guide pins are included
for assuring proper alignment between the front and rear sections.
The adjustable gap between the front and rear sections of the
flex-plate adapter provides compensation for thread wear. A
magazine cutoff provides a manual cutoff for retaining ammunition
in the magazine whether the rifle is assembled or disassembled. A
cutoff lock prevents the accidental movement of the magazine
cutoff.
Inventors: |
Clay, David Richard;
(Arlington, TX) |
Correspondence
Address: |
James E. Bradley
BRACEWELL & PATTERSON, LLP
Suite 2900
711 Louisiana Street
Houston
TX
77002-2781
US
|
Family ID: |
25103300 |
Appl. No.: |
09/775090 |
Filed: |
January 31, 2001 |
Current U.S.
Class: |
42/75.02 |
Current CPC
Class: |
F41C 7/06 20130101; F41A
21/484 20130101; F41A 11/04 20130101; F41A 11/00 20130101 |
Class at
Publication: |
42/75.02 |
International
Class: |
F41A 021/00 |
Claims
I claim:
1. An apparatus for barrel adjustment in a takedown firearm, the
apparatus comprising: a front section and a rear section, a
distance between a forward surface of the rear section and rearward
surface of the front section being adjustable, a forward surface of
the front section being adapted to abut a rearward surface of a
fore-end of a firearm, a rearward surface of the rear section being
adapted to abut a forward surface of a receiver of the firearm; an
upper opening extending through both sections and adapted to
receive a rear portion of a barrel; and at least one pin for
maintaining alignment of one of the sections to the other of the
sections, the pin extending from one of the sections and being
received by a socket in the other of the sections.
2. The apparatus of claim 1, further comprising a lower opening
extending through both sections and adapted to receive a rear
portion of a magazine.
3. The apparatus of claim 1, wherein: the distance is adjusted by
at least one screw which connects the sections to one another.
4. The apparatus of claim 3, wherein: the at least one screw
comprises at least two screws; and the screws are individually
adjustable for changing the planar orientation of the sections to
each other.
5. The apparatus of claim 2, further comprising: a magazine cutoff
extending through one of the sections transverse to the lower
opening and adapted to selectively prevent ammunition stored in the
magazine from passing through the lower opening.
6. The apparatus of claim 5, wherein: the magazine cutoff comprises
a pin that is selectively movable between a first position and a
second position, the first position being adapted to prevent
ammunition carried in the magazine from passing through the lower
opening, the second position being adapted to allow ammunition to
move through the lower opening.
7. The apparatus of claim 6, further comprising: a magazine cutoff
lock mounted to one of the sections for selectively preventing the
movement of the magazine cutoff between the first and second
positions.
8. In a takedown firearm having a fore-end which carries a barrel
and a magazine and is detachable from a receiver, the improvement
comprising: a front section and a rear section, a distance between
a forward surface of the rear section and rearward surface of the
front section being adjustable, a forward surface of the front
section abutting a rearward surface of the fore-end of the firearm,
a rearward surface of the rear section being abutting a forward
surface of the receiver of the firearm; an upper opening extending
through both sections and receiving a rear portion of the barrel; a
lower opening extending through both sections and receiving a rear
portion of the magazine; at least one pin for maintaining alignment
of one section to the other, the pin extending from one of the
sections and being received by a socket in the other of the
sections; at least one screw which connects the sections to one
another; and a magazine cutoff mounted to one of the sections that
is selectively movable to at least partially obstruct the lower
opening and to selectively prevent ammunition stored in the
magazine from passing through the lower opening.
9. The apparatus of claim 8, further comprising: threads located in
the upper opening of the front section for securing to threads
located on the rear portion of the barrel.
10. The apparatus of claim 8, wherein: the at least one screw
comprises at least two screws; and the screws are individually
adjustable for changing the planar orientation of the sections to
each other.
11. The apparatus of claim 8, wherein: the magazine cutoff
comprises a pin extending transversely through one of the sections,
the pin being selectively movable between a first position, in
which ammunition carried in the magazine is prevented from passing
through the lower opening, and a second position, in which
ammunition is allowed to move through the lower opening.
12. The apparatus of claim 11, further comprising: a magazine
cutoff lock for selectively preventing the movement of the magazine
cutoff between the first and second positions.
13. A method of assembling a takedown firearm having a barrel, a
fore-end, and a magazine, the method comprising: (a) providing an
adapter having front and rear sections; (b) inserting the barrel
into an upper opening extending through both sections; (c)
inserting the magazine into a lower opening extending through both
sections; (d) adjusting screws connecting the sections to one
another to select a distance between the sections and to select a
planar orientation of the sections relative to each other; and (e)
securing the barrel to the receiver, abutting a rearward surface of
the fore-end of the firearm with the front section, and abutting a
forward surface of a receiver of the firearm with the rear
section.
14. The method of claim 13, wherein step (b) further comprises:
securing threads located in the upper opening of the front section
to threads on the barrel.
15. The method of claim 13, further comprising: selectively
preventing ammunition carried in the magazine from exiting the
magazine by at least partially obstructing the lower opening of one
of the sections.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to firearms and
particularly relates to takedown firearms.
[0003] 2. Description of the Prior Art
[0004] Takedown lever-action rifles are a type of lever-action
rifle that is particularly popular. The term "takedown rifle"
describes a rifle in which the barrel and fore-end are readily
connected with and detached from the buttstock and receiver frame
so as to permit the rifle to be more easily packed and compactly
transported.
[0005] During World War II, the Japanese developed a takedown rifle
for issue to airborne units. A standard bolt-action rifle was
modified to accommodate a special barrel with interrupted threads
at its chamber end that mated with threads on a sleeve provided at
the front end of the receiver. This rifle proved to be
unsuccessful. Thereafter, another version was developed which
featured a barrel locked in place by means of a tapered wedge but
its accuracy at best was mediocre.
[0006] Rifles utilizing a takedown feature are shown in U.S. Pat.
Nos. 529,455; 534,691; 605,111; 605,734; 616,719; 755,660; 855,181;
1,065,341 and 1,370,836. In spite of numerous developments in the
art of takedown rifles, virtually all such rifles suffer from the
inability to "hold zero," or repeat the point-of-aim after the
barrel has been repeatedly removed and reinstalled. Lever-action
rifles, in particular, suffer because they are used for hunting and
are frequently disassembled. This disassembly/assembly operation
puts stress on the threads in the barrels and receivers, causing
the barreled fore-end and front sight to be misaligned with the
receiver and rear sight when completely assembled.
[0007] Deviation is not acceptable for long range precision
shooting such as may be required for target use or sniper use by
the military and law enforcement organizations. In order to obtain
the degree of accuracy considered acceptable for sniper or target
shooting, all components of any rifle, and particularly a takedown
rifle, must fit together in an extremely tight manner with very
close tolerances. Without the means to compensate for wear,
particularly wear of the threads in mating parts, any rifle that is
repeatedly disassembled and reassembled will lose its accuracy,
resulting in a change in the point of impact of the bullet.
[0008] The ammunition magazine for lever-action rifles is typically
located beneath, and attached to, the barrel. Generally, ammunition
in the magazine of a takedown rifle is retained in the magazine
only while the rifle is completely assembled. There is no provision
for retaining ammunition therein while disassembled. Thus, when the
rifle is reassembled, ammunition must be loaded into the magazine
through the rifle's receiver.
[0009] Consequently, there is a need to provide a takedown
lever-action firearm that can be repeatedly disassembled and
reassembled with provision for maintaining its accuracy. There is
also a need for retaining ammunition in the magazine while the
weapon is disassembled to provide ready and immediate access when
reassembled.
SUMMARY OF THE INVENTION
[0010] It is therefore one object of the present invention to
provide a method and apparatus that will allow for easy assembly
and disassembly of the barrel to the receiver and effectively
compensate for wear in the threaded connection that mates the
barrel to the rifle.
[0011] It is another object of the present invention to provide an
apparatus for retaining ammunition in the magazine of the rifle
when disassembled.
[0012] A flex-plate adapter for a takedown firearm is provided
which has front and rear sections. The rear section includes
adjustment screws to change the gap between the front and rear
sections. Guide pins are included for assuring proper alignment
between the front and rear sections. The adjustable gap between the
front and rear sections of the flex-plate adapter provides
compensation for thread wear. A magazine cutoff provides a manual
cutoff for retaining ammunition in the magazine whether the rifle
is assembled or disassembled. A cutoff lock prevents the accidental
movement of the magazine cutoff.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The novel features believed to be characteristic of the
invention are set forth in the appended claims. The invention
itself however, as well as a preferred mode of use, further objects
and advantages thereof, will best be understood by reference to the
following detailed description of an illustrative embodiment when
read in conjunction with the accompanying drawings, wherein:
[0014] FIG. 1 is a side elevational view of a prior art takedown
firearm;
[0015] FIG. 2 is a an exploded view of the prior art takedown rifle
of FIG. 1 illustrating the means for connecting the barrel and the
receiver;
[0016] FIG. 3 is an enlarged rear view of a flex-plate adapter for
adjusting alignment of a takedown firearm barrel and retaining
ammunition in the magazine in accordance with a preferred
embodiment of the present invention;
[0017] FIG. 4 is a side elevational view of the adapter of FIG.
3.
[0018] FIG. 5 is a an exploded side elevational view of a takedown
firearm having an adapter in accordance with FIG. 3; and
[0019] FIG. 6 is a view of the flex-plate adapter of FIG. 3
partially assembled with the firearm of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0020] With reference now to the figures, and in particular with
reference to FIG. 1, a takedown firearm 100 is illustrated. Firearm
100 is, in this case, a lever-action rifle. Buttstock 102 is
generally constructed of non-metal material and is placed against a
shooter's shoulder for shooting. Lever 104 is part of a mechanism
which cocks the hammer of the rifle, ejects a spent ammunition
case, and chambers a live round of ammunition for firing. Trigger
guard 106 prevents an accidental trigger pull. Fore-end 108 is used
for holding the rifle. Magazine 110 is removably attached to barrel
112 and is used for storing a horizontal column of ammunition which
is spring-biased toward the receiver. The live round is inserted
into the firing chamber utilizing lever 104 mechanism prior to
firing. The spent cartridge is ejected from ejection slot 116 when
lever 104 is actuated to load a live ammunition round into receiver
114.
[0021] The lever-action rifle illustrated is a takedown rifle
showing the connecting mechanism between the barrel and the
receiver in FIG. 2. Generally, a takedown rifle utilizes a threaded
extension of the barrel to positively connect to the receiver.
Barrel connector 118, a threaded portion of barrel 112, is used to
connect to receiver 114. This feature of easy assembly, by
threading barrel 112 to receiver 114, allows for easy carrying and
storage of rifle 100. However, because of the frequency of use of
the takedown feature, the threads become worn over time and the
alignment of barrel 112 and receiver 114 changes.
[0022] Referring to FIGS. 3 and 4, a detailed view of a flex-plate
adapter for adjusting alignment of a takedown firearm barrel and
retaining ammunition in the magazine in accordance with a preferred
embodiment of the present invention is illustrated in a rear view
(FIG. 3) and a side view (FIG. 4). Flex-plate adapter 200 comprises
two sections: adjustment section 202 and receiver section 203.
Barrel opening 204 and magazine opening 206 are cylindrical and
extend through both sections 202, 203. The portion of opening 204
in section 203 is shown as having threads 205, though section 203
may be attached to barrel connector 118 by other means such as, for
example, soldering. The front surface of section 203 has a recess
207 shaped for receiving fore-end 108. Though not shown in the
figures, magazine opening 206 may have a relief cutout in the
forward area when used in larger caliber rifles, the cutout
providing sufficient clearance to allow larger cartridges to be
loaded into magazine 110.
[0023] Guide pins 209 protrude from the front surface of adjustment
section 202. When assembled, guide pins 209 are inserted into
receiving sockets 211 in receiver section 203. Allen screws 208,
210 connect the sections and adjust the distance from the front
surface of section 202 to the rear surface of section 203. As allen
screws 208, 210 are turned, the longitudinal length of adapter 200
changes. Allen screws 208, 210 are adjusted until the length of
adapter 200 is such that, when assembled, barrel 112 is tightly
fitted to receiver 114. Screws 208, 210 also may be adjusted
individually to alter the planar orientation of sections 202, 203
to each other for adjusting the point-of-impact of a bullet fired
from barrel 112. Only slight changes in the planar orientation are
required to adjust the vertical or horizontal position of the
forward end of barrel 112 (FIG. 1) relative to receiver 114 (FIG.
1). Guide pins 209 deflect a small amount if the planar orientation
is other than parallel.
[0024] Magazine cutoff 212 is used for retaining ammunition within
magazine 110 by partially blocking opening 206. Cutoff 212 is a
cylindrical pin extending transversely through section 203 and is
shown fully extended in the closed position which prevents
ammunition from exiting magazine 110 (FIG. 1). Screw 213 engages a
translating slot 214 in cutoff 212 for retaining and limiting the
travel of cutoff 212 within section 203. Screw 213 preferably has a
spring-biased plunger for engaging detents (not shown) in slot 214
as cutoff 212 is moved into the open and closed positions.
[0025] When cutoff 212 is moved to the open position, a cutout 215
aligns with the bottom of opening 206, permitting ammunition stored
in magazine 110 to feed into receiver 114. When disassembling the
rifle, cutoff 212 is pushed to the closed position to move cutout
215 out of alignment with opening 206, preventing ammunition from
exiting magazine 110. Cutoff lock 216 is located above cutoff 212
in section 203 and prevents accidental cutoff of ammunition. Lock
216 comprises a vertical plate within section 203 and an attached
head external to section 203. Lock 216 is spring-biased in a
downward direction by spring 218, and a lower portion of the
vertical plate of lock 216 engages notch 220 in cutoff 212 when
cutoff 212 is moved to the open position. To move cutoff 212 to the
closed position, lock 216 is pulled upward as cutoff 212 is
simultaneously moved to the closed position. Though shown in the
figures as a sliding type, cutoff 212 may also be rotary.
[0026] Referring now to FIGS. 5 and 6, flex-plate adapter 200 is
shown partially assembled to the fore-end portion 113 of a takedown
rifle. Barrel connector 118, a threaded portion of barrel 112, is
shown inserted into opening 204 of adapter 200. Threads 205 of
receiver section 203 engage threads on barrel connector 118. Allen
screws 208, 210 are shown in an extended position, illustrating the
adjustment feature of adapter 200. Gap 302 is a result of the
adjustment of allen screws 208, 210. Guide pins 209 are inserted
into sockets 211 for maintaining the alignment of adjustment
portion 202 with receiver portion 203 of flex plate 200.
[0027] Flex-plate adapter 200 is properly fitted and adjusted prior
to affixing section 203 to the barrel/fore-end portion 113 of the
takedown rifle. Receiver section 203 of flex-plate adapter 200
abuts fore-end 108 and receives barrel 112. To install the
combination of flex-plate adapter 200 and fore-end 113, barrel
connector 118 is threaded into receiver 114 until adjustment
section 202 abuts receiver 114 and the connection is completely
tightened. Necessary adjustments in gap 302 are made by removing
fore-end 113 and adapter 200 and adjusting allen screws 208, 210
until proper alignment of fore-end 113 to receiver 114 is achieved
when the rifle is reassembled. Compensation for any change in
travel of barrel connector 118 is made by adjusting gap 302 of
flex-plate adapter 200, thus increasing or decreasing the travel
distance of the threads of barrel connector 118 into receiver 114.
To allow ammunition to feed in to receiver 114, cutoff 212 is moved
from the closed position to the open position until lock 216
engages notch 220. To prevent ammunition from feeding, cutoff lock
216 is moved upward to disengage lock 216 from notch 220, and
cutoff 212 is moved to the closed position.
[0028] The adapter of the present invention has the advantage of
providing a means of compensating for thread wear in the connection
between the fore-end and receiver of a takedown firearm. By having
multiple screws connecting the front and rear sections of the
adapter, an additional advantage is that the point-of-impact can be
adjusted vertically and horizontally. Also, the magazine cutoff
allows for ammunition to be retained in the magazine when the rifle
is disassembled. The cutoff lock prevents accidental cutoff of the
magazine.
[0029] While the invention has been particularly shown and
described with reference to a preferred embodiment, it will be
understood by those skilled in the art that various changes in form
and detail may be made therein without departing from the spirit
and scope of the invention.
* * * * *