U.S. patent application number 11/137840 was filed with the patent office on 2006-01-19 for high velocity ammunition system and firearm.
This patent application is currently assigned to Smith & Wesson Corp.. Invention is credited to Richard J. Mochak.
Application Number | 20060011092 11/137840 |
Document ID | / |
Family ID | 35598084 |
Filed Date | 2006-01-19 |
United States Patent
Application |
20060011092 |
Kind Code |
A1 |
Mochak; Richard J. |
January 19, 2006 |
High velocity ammunition system and firearm
Abstract
A round of high velocity ammunition contained within a modified
chamber of a conventional firearm has a cartridge case, a sabot
mounted within the forward-end of the case and a carrying
projectile matching the caliber of the firearm for engaging rifling
in the firearm bore, and a quantity of a propellant charge
sufficient to impart a muzzle velocity in excess of 25,000
(ft./sec.) to the projectile. The cartridge case and the projectile
cooperate with a rearwardly facing abutment surface of the chamber
to confine the sabot which has an forwardly facing bearing surface
coaxially surrounding a portion of the projectile and in abutting
engagement with the abutment surface. When the round is fired
substantially instantaneous dynamic forces generated by the gases
of explosion propel the projectile from the chamber into and
through the bore while simultaneously comprising the sabot to a
fracture point. The fragmented sabot is entrained in the gases of
explosion and escapes from the firearm through the muzzle end of
the barrel.
Inventors: |
Mochak; Richard J.;
(Russell, MA) |
Correspondence
Address: |
MCCORMICK, PAULDING & HUBER LLP
CITY PLACE II
185 ASYLUM STREET
HARTFORD
CT
06103
US
|
Assignee: |
Smith & Wesson Corp.
Springfield
MA
|
Family ID: |
35598084 |
Appl. No.: |
11/137840 |
Filed: |
May 25, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60574246 |
May 25, 2004 |
|
|
|
Current U.S.
Class: |
102/522 |
Current CPC
Class: |
F41C 3/14 20130101; F41A
9/74 20130101; F41A 9/28 20130101; F42B 14/06 20130101; F42B 5/045
20130101 |
Class at
Publication: |
102/522 |
International
Class: |
F42B 14/06 20060101
F42B014/06 |
Claims
1. The combination comprising; a firearm, and a cartridge disposed
in firing position within said firearm, said firearm having a
generally cylindrical axially extending bore including a breech end
and a forward or muzzle end, and a cylindrically stepped cartridge
chamber in coaxial communication with said breech end, said chamber
including a front portion having a diameter substantially equal to
the diameter of said bore, a rear portion having a diameter
substantially larger than the diameter of said front portion and a
generally rearwardly facing annular abutment surface forming a
transition between said front and rear portions for complimentary
abutting engagement with a bearing surface on an associated
cartridge received in a firing position within said chamber, said
cartridge having a cylindrical case slideably received within said
rear portion and including a mouth opening at its forward end and a
base forming a closure for its rear end, a sabot received within
said mouth and supported within said case, said sabot having a
forwardly open projectile receiving bore an annular forwardly
facing surface coaxially surrounding said projectile receiving bore
and comprising said bearing surface, a projectile received and
supported within said projectile receiving bore and extending for
some distance into said forward portion, and a quantity of
explosive propellant contained within said case rearward of said
sabot for propelling said projectile out of said chamber and into
and through said bore and for fracturing and fragmenting said sabot
within said chamber and propelling the fragments of said sabot from
said chamber into and through said bore and discharging said
fragments at said muzzle end when said cartridge is fired.
2. The combination set forth in claim 1 wherein said abutment
surface and said bearing surface comprise opposing radially
disposed surfaces.
3. The combination set forth in claim 1 wherein said abutment
surface comprises a generally conical rearwardly diverging surface
centered on the axis of said chamber.
4. The combination set forth in claim 3 wherein said at least one
bearing surface is defined by a conical surface of revolution
centered on the axis of said cartridge.
5. The combination as set forth in claim 1 wherein said sabot is
partially defined by a plurality of circumaxially spaced apart and
axially forwardly projecting petals.
6. The combination set forth in claim 1 wherein said sabot has a
plurality of distinct barring surfaces thereon.
7. The combination as set forth in claim 6 wherein said sabot is
partially defined by a plurality of distinct axially forwardly
extending petals and each of said petals defines in associated one
of said distinct bearing surfaces.
8. The combination set forth in claim 1 wherein said projectile has
a generally cylindrical rear portion received in press fit within
said projectile receiving bore.
9. The combination set forth in claim 8 wherein said sabot is
received and retained in press fit within said case.
10. The combination as set forth in claim 9 wherein said case is
crimped radially inwardly at said mouth opening to further retain
said sabot in said case.
11. The combination set forth in claim 1 wherein said projectile
has an ogival forward portion forming a transition with a generally
cylindrical trailing portion.
12. The combination set forth in claim 1 wherein said projectile
receiving bore is a stepped bore including a rear portion, a front
portion having a diameter larger than the diameter of said rear
portion and a radially disposed and forwardly facing shoulder
forming a transition between said front and rear portions.
13. The combination as set forth in claim 12 wherein said stepped
bore comprises a blind bore and said sabot has a generally
rearwardly facing end wall forming a closure for the rear end of
said projectile receiving bore.
14. The combination as set forth in claim 13 wherein said rear wall
has a generally radially disposed rear surface.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is entitled to the benefit of and
incorporates by reference essential subject matter disclosed in
U.S. Provisional Patent Application No. 60/574,246, filed May 25,
2004.
FIELD OF THE INVENTION
[0002] This invention relates in general to high velocity firearms
and associated high velocity ammunition and deals more specifically
with improvements in hand guns, particularly revolvers and high
velocity ammunition for such firearms.
BACKGROUND OF THE INVENTION
[0003] Bottleneck ammunition is well known in the firearm art and
is usually used in rifles, particularly those of bolt-action type,
and other long guns. A typical bottleneck ammunition cartridge
includes an axially elongated cartridge case which has a
cylindrical forward end portion within which a projectile or bullet
is supported, a generally cylindrical rear end portion which has a
base and a major diameter substantially greater than the diameter
of the forward end portion, which carries the projectile. A
neck-down portion disposed intermediate the front and rear portions
of the cartridge case provide smooth transition there between. This
bottleneck cartridge case configuration allows for the provision of
a relatively large amount of a propellant charge to be contained
within the rear portion of the case as is necessary for the
attainment of a high muzzle velocity. The term "high velocity", as
hereinafter used, is intended to mean a muzzle velocity in excess
of about 2,500 feet per second (ft./sec.).
[0004] Previous attempts to use bottleneck type cartridges with
revolvers have proven generally unsuccessful. Such cartridges tend
to expand when fired and drive the spent cartridge case in a
rearward direction and toward the standing breech or bolster
surface on the revolver frame at the immediate rear of the revolver
cylinder. This condition may be attributed to some of the force
generated by the gases of explosion in firing the cartridge being
dissipated against the inner surfaces of the cylindrical and
neck-down portions of the case, resulting in a net force vectoring
the cartridge case in a rearward direction. Consequently, rotation
of the revolver cylinder is likely to be inhibited if not
precluded. It has also been found that if none of the cartridge
cases are driven against the revolver frame with sufficient force
to inhibit or preclude proper cylinder indexing rotation and or
movement of the cylinder between open and closed positions relative
to the revolver frame, extraction of the spent cases may be only
marginally satisfactory if not totally unacceptable.
[0005] It is the general aim of the present invention to provide
and improve ammunition system to allow for sufficient propellant
charge or powder quantity to generate the energy necessary to
achieve desired velocities while retaining the desired consistent
functional characteristics of the firearm with which the ammunition
is used.
[0006] It is a further aim of the present invention to provide
improved handguns and particularly revolvers for effectively
employing ammunition of the present invention while assuring
consistent trouble free functionality of the action of the gun in
which the cartridge is fired.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, a firearm for use
with a round of high velocity ammunition also embodying the
invention and having a projectile matching the caliber of the
firearm bore and for engaging rifling in the bore. The projectile
is carried by a sabot mounted within a diametrically enlarged
cartridge case containing a propellant charge capable of propelling
the projectile from the firearm at a high muzzle velocity. Further,
and in accordance with the invention, the firearm has a chamber
configured and dimensioned to cooperate with the cartridge case and
the projectile to confine the nonmetallic sabot so that it will be
compressed to a point of fragmentation and fragmetized by the
dynamic forces generated by expansion of the gases of explosion
when a high velocity propellant charge contained within the
diametrically enlarged cartridge case. When the firearm is
discharged, dynamic forces generated by the substantially
instantaneous expansion of the gases of explosion compress and
fragmentize the sabot. The sabot fragments, entrained in the
escaping gases of explosion, travel through the firearm bore and
escape from the firearm at its muzzle end.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side elevational view of a revolver embodying
the present invention and utilizing the ammunition system of the
present invention.
[0009] FIG. 2 is a fragmentary side elevational view of the
revolver of FIG. 1 shown with the cylinder in open position.
[0010] FIG. 3 is a sectional view taken along the line 3-3 of FIG.
2.
[0011] FIG. 4 is an exploded perspective view of the revolver
cylinder and shows the cylinder support yoke and the extractor
mechanism.
[0012] FIG. 5 is a somewhat enlarged rear view of the revolver
cylinder.
[0013] FIG. 6 is a somewhat enlarged rear elevational view of the
extractor.
[0014] FIG. 7 is a somewhat enlarged schematic view illustrating
the cylinder indexing mechanism.
[0015] FIG. 8 is a somewhat enlarged axial sectional view through a
cartridge embodying the ammunition system of the present
invention.
[0016] FIG. 9 is a sectional view taken along the line 9-9 of FIG.
8.
[0017] FIG. 10 is a sectional view taken along the line 10-10 of
FIG. 8.
[0018] FIG. 11 is a perspective view of the sabot shown in FIGS.
8-10.
[0019] FIG. 12 is an axial sectional view through a revolver
cylinder 12 chambered in accordance with the invention and shown
with cartridges embodying the present invention in the chargeholes
of the cylinder.
[0020] FIG. 13 is similar to FIG. 8, but shows another cartridge
embodying the ammunition system of the present invention.
[0021] FIG. 14 is an axial sectional view taken along the line
14-14 of FIG. 13.
[0022] FIG. 15 is a sectional view taken along the line 15-15 of
FIG. 13.
[0023] FIG. 16 is a perspective view of the sabot shown in FIGS.
13-15.
[0024] FIG. 17 is an axial sectional view through yet another
cartridge embodying the ammunition system of the present
invention.
[0025] FIG. 18 is a sectional view taken along the line 18-18 of
FIG. 17.
[0026] FIG. 19 is a sectional view taken along the line 19-19 of
FIG. 17.
[0027] FIG. 20 shows another revolver cylinder for use with the
revolver of FIG. 1 to fire cartridges shown in FIGS. 17-19.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Turning now to the drawings, a high velocity firearm or
revolver embodying the present invention and particularly adapted
to fire high velocity ammunition embodying the invention is shown
in FIG. 1 and indicated generally by the reference numeral 10. The
illustrated firearm 10 is a modified Model 500 Smith & Wesson
Revolver, manufactured by Smith & Wesson Corp., Springfield
Mass., assignee of the present invention, and includes a frame 12
and an axially elongated barrel 14 mounted in fixed position and
projecting in and axially forward direction from the frame. The
barrel defines a rifled bore, 16 which extends axially through it
from a breech or rear end to a forward or muzzle end. The revolver
10 further include a rotary cylinder 18, which is supported for
indexable rotation relative to the frame has a circumaxially series
of equangularly spaced apart chargeholes 20,20 extending
therethrough. The chargeholes are chambered in accordance with the
present invention to receive high velocity ammunition embodying the
present invention, as will be hereinafter further discussed.
[0029] Referring now particularly to FIGS. 2 and 3. The cylinder
18, shown somewhat schematically, is supported on the frame 12 by a
yoke 22 to pivot relative to the frame and about an axis 24 between
a closed or firing position wherein the cylinder is disposed within
an opening 25 defined by the frame and shown in FIG. 1, and an open
position, shown in FIGS. 2 and 3, wherein the cylinder is disposed
generally adjacent the left side of the frame 12. In the cylinder
open position extracted spent cartridges may be dumped from the
cylinder to permit cylinder reloading. A cylinder release mechanism
(not shown) normally biased to a cylinder retaining position
secures the cylinder 18 in closed position within the frame opening
25, as previously discussed. A thumb piece 26 located on the left
side of the frame 12 rearward of the cylinder 18 is operable to
release the cylinder from closed position and allow it to be
rotated out of the frame opening 25 and to open position. Further
disclosure of a cylinder supporting yoke and the manner in which a
revolver cylinder may be supported on a revolver frame for pivotal
movement between open and closed positions is found in U.S. Pat.
No. 1,181,417 to Wesson, which is hereby adopted by reference as
part of the present disclosure.
[0030] The revolver 10 has an extractor of conventional type for
removing spent cartridge cases from the charge holes or chambers
20,20 of the revolver cylinder 18 as shown in FIG. 4. The
extractor, indicated generally at 28 comprises a star or extractor
plate 30 mounted in a recess in the rear surface of the cylinder
18. The extractor plate 30 is mounted on the rear end of a tubular
stem 32 and has a plurality of radially extending arms 34,34
equangularly spaced about the axis of the stem 32 and defining
between each adjacent pair of arms a parti-cylindrical surface
which conforms with the inner-cylindrical surface portion of one of
the cartridge chambers 20 formed in the revolver cylinder 18. The
extractor plate 30 also includes, on its rear surface, a rearwardly
projecting ring or annulus 29 on which there are formed a plurality
of ratchets (not shown), equal in number to the chambers 20,20, for
a purpose which will be hereinafter further explained. The depth of
the recess within which the extractor plate 30 is received is
substantially equal to the thickness of the extractor plate, so
that the rearwardly facing surfaces of the extractor plate and the
cylinder 18 are disposed within a substantially common radial plane
when the cylinder 18 is retained in closed or firing position. In
the latter position the curved inner edges on the extractor plate,
defined by the arms 34,34 are disposed forward of a rim on each of
the cartridge cases disposed within the cylinder 18. After the
cartridges in the cylinder have been fired, the cylinder retaining
mechanism has been operated, and the cylinder has been moved out of
the frame opening 25 and to it's open position, a rearward thrust
on the extractor or stem rod will cause the spent cartridge,
cartridges to be pushed rearwardly and out of their respectively
associated charge holes for dumping to permit reloading.
[0031] A more complete disclosure of a presently preferred
extractor mechanism for use in practicing the present invention is
found in my earlier U.S. Pat. No. 5,218,148, which is hereby
adopted by reference as part of this disclosure.
[0032] The illustrated revolver, which embodies the present
invention, also includes a conventional cylinder indexing mechanism
shown somewhat schematically in FIG. 7 and indicated generally by
the reference numeral 36. The indexing mechanism includes a trigger
38 for operating a firing mechanism (not shown). The trigger 38 is
pivotally supported on the frame 12 by a pivot pin 40. A hand 42
pivotally connected to the trigger is configured to cooperate with
the ratchet, one of the cylinder chambers 20,20 into coaxial
alignment with the bore each time the trigger is operated. As each
of the chambers 20,20 is indexed into alignment with the barrel a
latch 42 associated with the trigger mechanism moves into latching
engagement within an associated keeper opening in the cylinder to
secure the cylinder in its position during the firing cycle. A more
complete disclosure of such an indexing mechanism is found in U.S.
Pat. No. 6,571,502 to Mikuta, assigned to the assignee of the
present invention and hereby adopted by reference as part of the
present disclosure.
[0033] It is anticipated that the ammunition system of the present
invention will prove suitable for use with a wide variety of types
of firearms. A revolver having operational characteristics which
particularly suitable for use with ammunition in accordance with
the present invention having been hereinbefore described ammunition
embodying the present invention will now be considered and with
particular reference to the inventive concepts of the firearm
chamber within which it is received.
[0034] Referring now particularly to FIGS. 8-10 a cartridge or
round of ammunition embodying the ammunition to system of the
present invention is indicated generally by the reference numeral
50. The illustrated cartridge 50 essentially comprises a case 52 a
projectile or bullet 54 a sabot 56 for positioning and supporting
the projectile within the case and a predetermined quantity of a
propellant or outer charge suitable for imparting to the projectile
a muzzle velocity in excess of 2,500 (ft./sec.).
[0035] The invention is preferably practiced with metal, rimed
cartridges of centerfire type the case being preferably fabricated
from brass. The case may be characterized as an axially elongated
generally cylindrical thin walled shell which includes a radially
disposed base 60 at its rear end percussion cap or primer is
mounted centrally within a rearwardly open recess in the base wall
and communicates with the interior of the case through a central
bore opening 62. The major diameter of the case ranges from about
0.4 in. to about 0.5 in.
[0036] The invention maybe practiced with projectiles of various
kinds. The presently preferred projectile 54 has an ogival head
portion indicated at 64 which forms a transition with a generally
cylindrical trailing portion 66 having an axial length
approximately equal to the length of the end portion 64. In
accordance with the invention, the projectile 54 is matched to the
caliber of the firearm with which it is to be used and it is
intended that the projectile engage the bore rifling in a
conventional manner. Preferably, the present projectile has a major
diameter ranging from about 0.264 in. to about 0.308 in.
[0037] A sabot is conventionally used as a carrier for a
sub-caliber projectile engages the bore or rifling of a firearm
from which the projectile is fixed. However, in accordance with the
present invention, the only function of the sabot 56 is to position
and support the relatively small diameter projectile in coaxial
alignment with the substantially larger diameter case 52. The
present sabot, is preferably molded otherwise formed from a
somewhat resilient lightweight non metalic plastic material. It has
an axially elongated generally cylindrical body with a coaxial
stepped bore 68. The bore 68 has a generally cylindrical front-end
portion 70 a rear-end portion 72 of somewhat smaller diameter and a
radially disposed annular shoulder 74 which forms a transitional
surface between the front portion and the dramatically reduced rear
portions of the sabot bore 68. Generally radially disposed annular
surfaces 76 and 78 coaxially surround the front and rear bore
portions 70 and 72, substantially as shown. The axial length of the
front portion 70 is substantially equal to the axial length of the
projectile trailing portion 66 which is received in press fit
within the front portion 70 of the sabot bore whereby the
projectile 54 is located relative to sabot 56. The sabot 56 is, in
turn and with the rear surface of the projectile in engagement with
the shoulder 74 of the sabot received within the case 52 through
the mouth thereof and is disposed in press fit engagement with the
case. The forward end portion of the case which defines the mouth
thereof is crimped into engagement with the sabot proximate the
frontal bearing surface 76 of the sabot. Thus, the latter radially
disposed frontal surface is exposed at the mouth of the cartridge
for complementary abutting engagement with the transitional
abutment surface of the chamber 20.
[0038] Referring now to FIG. 12 the cartridge 50 is shown in its
firing position within an associated chamber 20 of the revolver
cylinder 18. In accordance with the invention the chamber 20 has a
cylindrical stepped bore extending through it. The bore 20 has a
cylindrical forward end portion 80 sized to receive the projectile
54 therethrough and provide smooth transition into the barrel bore.
The substantially larger rear portion of the chamber 20, indicated
by the numeral 82 is sized to receive the cartridge case in a
conventional manner. A generally radially disposed and rearwardly
facing abutment surface 84 forms a transition between the forward
and rear portions of the chamber 20.
[0039] When the cartridge 50 is loaded in an associated cylinder
chamber 20 the radial bearing surface at the forward-end of the
sabot, is disposed in abutting engagement with the rearwardly
facing annular abutment surface of the chamber.
[0040] When the round 50 is fired the substantially instantaneous
increase in pressure generates dynamic forces acting upon the
exposed rear surfaces of the projectile 54 and the sabot 56
sufficient to impart to the projectile the desired velocity while
simultaneously compressing the sabot to a point of fracture at
which point it acquires brittle characteristics so that the dynamic
forces acting upon it cause it to fracture, and fragment. The
resulting sabot fragments become entrained in the gases of
explosion leaving the barrel through the muzzle of the firearm.
Experimental firing has indicated that all of the relatively light
sabot material leaves the barrel through the muzzle. However,
should any sabot material remaining in the spent cartridge it will
be removed from the chamber with the extracted spent cartridges.
Initial indications are that sabot residue will not be a
problem.
[0041] Referring now to FIG. 13 of the drawings another round of
ammunition embodying the ammunition system of the present invention
is shown. And is indicated generally by the reference numeral 50a.
The round 50a is similar, in most respect, to the round 50
previously described and parts of the round 50a which are
substantially identical to parts of the previously describes round
50 bear the same reference numerals and a letter "a" suffix and
will not be hereinafter further described. Like the round of
ammunition 50, the round 50a includes a cartridge case, 52a
projectile 54a and a propellant charge 58a. However, the sabot used
in the round 50a has a circumaxally spaced apart series of axially
forwardly extending pedal 88,88. The number of pedals provided may
vary, however, the illustrated sabot has four (4) such pedals
defined by an equangularly spaced apart series of axially
rearwardly extending slots 90,90, substantially as shown. The
forwardly facing surfaces of the pedals comprise surfaces which are
disposed in generally abutting engagement with a reawardly facing
annular abutment surface of the modified chamber 20. The provision
of pedals on an otherwise generally cylindrical sabot alter the
projectile holding characteristics of the sabot to provide faster
release of its associated projectile, where desired.
[0042] Yet another cartridge or round of ammunition embodying the
present ammunition system is shown in FIGS. 17-19 and indicated
generally by the reference numeral 50c. The illustrated round 50
differs from the previously described round 50b both in the
construction and arrangement of its sabot and in the length of its
cartridge case 52c. Specifically, the sabot 56c has a plurality of
circumaxially spaced apart axially forwardly extending petals 88c,
88c, six shown. The petals extend for some distance beyond the
mouth of the cartridge case. Each petal 88c has a generally
forwardly facing bearing surface 92. The bearing surfaces 92, 92
are defined by a rearwardly diverging conical surface of revolution
centered on the central axis of the sabot. These surfaces are
disposed in abutting engagement with complimentary surfaces on the
transitional surface of the chamber of the firearm, as previously
discussed. Since the overall length of the cartridge 52c is
dictated by the axial length of an associated revolver cylinder
18c. The case 52c is shortened to allow for the bearing surfaces on
the sabot which project forwardly beyond the mouth of the cartridge
at substantially as shown in FIG. 17.
* * * * *