Recoil reducing device

A recoil reducing device for use with firearms including handguns and rifles which includes a core and a sleeve that surrounds the core. The core and the sleeve each have a plurality of radially directed openings along their lengths that are cooperatively aligned with respect to each other. The openings are oriented with respect to a central bore of the core such that combustion gases generated by firing the firearm, noise and any unburnt gunpowder are directed away from a shooter, and recoil and muzzle rise of a firearm are substantially reduced.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a recoil reducing device for use with firearms, 
and, more particularly, to a recoil reducing device that directs hot 
combustion gases generated during firing, associated firing noise and 
unburnt gunpowder in a direction away from the shooter, and substantially 
reduces recoil and muzzle rise. 
2. Discussion of the Related Art 
It has been known in the art to attach recoil reducing devices to firearms, 
including handguns, rifles and shotguns, to reduce the amount of recoil 
generated when firearms are fired. Such known devices have generally been 
attached to the muzzle end of the barrels of the firearms. The known 
devices have defined a longitudinal bore in axial communication with the 
bore of the firearm barrel, and a plurality of radially directed openings 
extending from the inner diameters of the devices to their outer surfaces. 
The radially directed openings have had various orientations relative to 
the bore axes of these devices. They have been provided to function as 
alternate flow paths for the hot combustion gases created during firing so 
that all of the combustion gases are not forced to exit at the discharge 
end of the device. Some of the combustion gases flow away from the 
direction of the bore axis, and consequently reduce the amount of recoil 
in comparison to firearms not having such attached recoil reducing 
devices. 
The known devices have comprised muzzle brakes as exemplified by U.S. Pat. 
Nos. 4,930,396 to Johnson, 4,930,397 to Seidler and 5,036,747 to McClain, 
III; compensators as exemplified by U.S. Pat. No. 2,451,514 to Seig; and 
other similar recoil reducing devices as exemplified by U.S. Pat. Nos. 
2,883,781 to Harvey and 4,459,895 to Mazzanti, Italian Patent No. 578,369 
and British Patent No. 445,821. 
The known recoil reducing devices have defined bores, and along their 
lengths radially directed gas flow openings emanating from the bores. 
These openings have been arranged at varying directions and angles with 
respect to their bore axes, and, accordingly, the bore axes of the 
firearms to which they have been attached. The known devices have defined 
radial openings oriented perpendicular and at oblique angles, both 
forwardly and rearwardly relative to their bore axes. 
For example, Harvey discloses a device that reduces recoil. The device 
defines perpendicularly oriented radial openings that are undesirable 
because only a limited amount of the combustion gases traveling through 
the bore of the device can abruptly change their direction of travel so as 
to enter the radial openings and be expelled therethrough. Consequently, 
most of the combustion gases still exit the bore at the discharge end of 
the device, as would be the case if the firearm did not have the attached 
device of Harvey. Therefore, recoil is not adequately reduced. 
Other recoil reducing devices have been provided that include radially 
directed openings oriented at oblique angles relative to their bore axes 
such as disclosed in Johnson, Seidler, McClain III and British Patent No. 
445,821. The radial openings in the Johnson and Seidler devices are angled 
forwardly relative to a perpendicular line extending relative to their 
bore axes, and direct expelled combustion gases in about the same forward 
directions. The radial openings include forward walls with which the gases 
collide during travel through the openings. Such collisions cause some of 
the momentum of the traveling gases to be transferred to the device as a 
forward directed force that urges the firearm forwardly away from the 
shooter, and, consequently, reduces the amount of recoil. 
The McClain device also includes forwardly angled radial openings, and 
associated baffles positioned in surrounding relationship to the radial 
openings that direct the gases that have passed through the radial 
openings in a rearward direction toward the shooter. The collision of the 
expelled gases with the baffles causes some of their momentum to be 
transferred to the firearm and directed forwardly along the longitudinal 
length of the device so as to reduce the amount of recoil. The baffles, 
however, at the same time cause the undesirable and potentially dangerous 
effect of deflecting the expelled gases and their associated noise, as 
well as any unburnt gunpowder, toward the shooter. 
British Patent No. 445,821 discloses a recoil reducing device which 
includes radially directed openings, each having an inner portion directed 
forwardly of a line extending perpendicularly to the bore axis, and an 
outer portion directed rearwardly of the perpendicular line through the 
remainder of the thickness of the longitudinal wall of the device. The 
outer rearwardly angled portions direct the expelled gases toward the 
shooter. Thus, this device is also inadequate. 
Italian Patent No. 578,369 discloses a recoil reducing device including 
radially directed openings each having an inner portion oriented 
perpendicularly to the bore axis, and an outer portion directed rearwardly 
relative to the perpendicular. The inner and outer portions of the 
openings are in flow communication with each other. The outer portions 
direct the expelled gases toward the shooter, and thus this device is also 
inadequate. 
Mazzanti discloses a recoil reducing device defining radial openings 
oriented perpendicular to its bore axis. The openings include beveled 
portions at their rear walls that direct the combustion gases against the 
forward walls of the openings. The escaping gases collide with the forward 
walls and are deflected rearwardly at an oblique angle relative to the 
bore axis, again toward the shooter. 
Finally, the Seig recoil reducing device defines radial openings including 
inner forwardly angled portions, and outer rearwardly oriented deflecting 
flanges associated with the inner portions, defining spaces therebetween. 
Ports are located in flow communication with the openings and spaces 
through which the combustion gases finally escape from the device after 
being deflected by the flanges. 
In view of the known recoil reducing devices, there has been a need for a 
recoil reducing device defining radial openings therein such that firearm 
recoil and muzzle rise are substantially reduced, and expelled combustion 
gases and associated noise, and unburnt gunpowder, are directed 
substantially away from the shooter to eliminate these undesirable and 
potentially hazardous aspects associated with prior art recoil reducing 
devices. 
SUMMARY OF THE INVENTION 
The present invention has been made in view of the above inadequacies of 
the prior art and has as an object to provide a recoil reducing device for 
use with firearms including handguns and rifles which can be easily 
attached to them. 
It is another object of the present invention to provide a recoil reducing 
device including radially directed openings for directing combustion gases 
generated by the firing of a firearm in a direction away from the bore 
axis of the device to reduce the amount of recoil and muzzle rise. 
It is a further object of the present invention to provide a recoil 
reducing device defining an arrangement of radially directed openings such 
that substantially all of the expelled combustion gases, noise and unburnt 
gunpowder are directed away from the shooter. 
To achieve the objects of the invention, as embodied and broadly described 
herein, the recoil reducing device of the present invention includes a 
core defining a bore having a bore axis, and including an inner 
longitudinal cylindrical wall. The inner longitudinal wall includes a 
plurality of inner openings that are substantially forwardly oriented at 
an oblique angle relative to the bore axis. 
The recoil reducing device in accordance with the present invention further 
includes a sleeve that is positioned in surrounding relationship to the 
core. The sleeve includes an outer longitudinal wall which has a plurality 
of outer openings that are oriented perpendicularly to the bore axis and 
are in flow communication with the inner openings. The outer openings 
direct substantially all of the combustion gases expelled from inner 
openings of the core of the device during firing away from the shooter. 
In another embodiment of the present invention, the forward walls of the 
inner openings include portions that are oriented substantially 
perpendicularly to the bore axis.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The preferred embodiments of the present invention will now be described in 
detail with reference to the accompanying drawings. 
FIGS. 1 and 2 illustrate a recoil reducing device 20 in accordance with the 
present invention attached to an end portion of a barrel 10 of a firearm. 
The barrel includes exterior male threads 11 at an end portion as best 
shown in FIG. 1. The threads 11 are engaged with female threads 21 of the 
recoil reducing device that are located within its rear end portion as 
will be described in greater detail below. The firearm may be a handgun or 
a rifle, and may be of essentially any caliber. 
In accordance with the present invention, the recoil reducing device 
includes a core 30 as illustrated in FIG. 1. The core defines a 
cylindrical bore 31 along its entire length. The cylindrical bore has an 
inner diameter that is substantially equal to the inner diameter 12 of the 
barrel. The inner diameter of the device may be varied along the length of 
the device to control the flow of the combustion gases therethrough as 
will be described in greater detail below. The inner diameter may also be 
varied to make the device compatible with the barrels of firearms of 
different calibers. 
The core includes an enlarged conical portion 32 at its rear end. The 
enlarged portion has an outer diameter that increases along the direction 
of the bore axis A--A of the device from the rear end 33 toward the front 
or discharge end 34 thereof. The enlarged portion includes a flat annular 
shoulder 35 that is substantially perpendicular to the bore axis. 
The cylindrical bore includes female threads 21 at its rear end, which 
extend toward the front end of the device to a position adjacent the 
shoulder 35 as illustrated in FIG. 2. The female threads have a 
configuration such that the recoil reducing device can be fitted directly 
to the exterior male threads on a barrel in order to attach the device to 
a firearm, as illustrated in FIG. 2. 
In those instances when the recoil reducing device is not attached to a 
firearm, a cap (not shown) including interior female threads and a bore 
coinciding with the bore of the firearm may be attached to the exterior 
threaded end of the firearm. 
The core 30 includes an elongated cylindrical portion 36 integral with the 
enlarged portion. The elongated cylindrical portion 36 includes an inner 
wall 37 having a plurality of inner openings 38 through its thickness. In 
accordance with the present invention, the inner openings emanate from the 
circumferential wall 39 of the bore and are substantially forwardly 
oriented at an oblique angle .THETA. relative to the bore axis. 
Preferably, the oblique angle equals approximately 45.degree. 
(.+-.5.degree.) so that the combustion gases are distributed away from the 
bore to the greatest possible extent. As illustrated in FIG. 2, the inner 
openings preferably each include a countersunk portion 40 that may have a 
concave shape. The countersunk portions terminate at their forward ends at 
arcuate-shaped forward wall portions 41 of the inner openings. The axis of 
the countersunk portions intersects the axis of the innermost portions at 
an angle so as to direct emanating gases generally perpendicularly with 
respect to the bore axis. The forward wall portions 41 and the forward 
wall portions 42 together define the forward faces of the inner openings. 
The forward wall portions 41 are adjacent to the outer surface 43 of the 
elongated cylindrical portion of the core. 
In accordance with another embodiment of the present invention, the inner 
openings may be oriented forwardly at an oblique angle relative to the 
longitudinal axis along their entire length as illustrated in FIG. 7. That 
is, the inner openings 38' may be formed without the countersunk portions 
illustrated in FIG. 2. 
In accordance with the present invention, the recoil reducing device 
further includes a sleeve 50 that is positioned in surrounding 
relationship to the core. The sleeve has a length that is substantially 
equivalent to the length of the elongated cylindrical portion 36 of the 
core. The sleeve is fitted over the elongated cylindrical portion so that 
its rear face 51 abuts the shoulder 35 of the core as illustrated in FIG. 
2. 
The sleeve 50 has a plurality of outer openings 52 which extend through the 
thickness of its outer longitudinal wall 53. In accordance with the 
invention, the outer openings are oriented substantially perpendicularly 
to the bore axis of the recoil reducing device. The outer openings are 
preferably circular shaped, but may optionally have other shapes such as 
oval. 
In accordance with the invention, the number of outer openings in the outer 
longitudinal wall of the sleeve may be varied, and preferably corresponds 
to the number of inner openings in the inner longitudinal wall of the 
core. When the sleeve is placed in surrounding relationship to the core, 
each of the outer openings are aligned with an associated inner opening so 
as to form a plurality of pairs of openings extending through the core and 
the sleeve of the recoil reducing device. These pairs of openings serve as 
side discharging flow paths for the hot, pressurized combustion gases. In 
fact, the vast majority of the gases are discharged through these radial 
openings, and not through the front, discharge end of the device. 
The openings may be formed in different patterns about the core and the 
sleeve so as to control the discharge of combustion gases from the device. 
For example, in the embodiment of the recoil reducing device illustrated 
in FIGS. 1 and 2, the inner and outer openings are located about 
longitudinal walls of the sleeve and core in a repeating pattern so as to 
effect substantially uniform gas discharge from the device. In the 
embodiment illustrated in FIGS. 5-7, however, there are two sets of inner 
and outer openings 38', 52' and 38", 52". 
The first set of openings 38', 52' are generally equally spaced about the 
periphery of the device adjacent the conical portion 32' and allow 
discharge of gases uniformly from the device. The second set of openings 
38", 52", however, extend longitudinally along only a portion of the 
device. In the illustrated embodiment, two rows of openings 38" and 52" 
are used. The second set of openings are preferably located along the 
upper portion of the device to provide a thrust or force to offset the 
natural tendency of the firearm to rise during recoil. The gases 
exhausting from the second set of openings will force the barrel of the 
firearm in a downward direction. 
In accordance with the present invention, the recoil reducing device is 
preferably composed of an alloy such as a chromium-molybdenum alloy or a 
tool steel. Other like alloys may also be used. Preferably, the chosen 
material is the same material used to form the barrel of the firearm so 
that both the firearm and the recoil reducing device may be simultaneously 
subjected to a blueing treatment. 
In accordance with the present invention, the recoil reducing device 
further comprises means for preventing relative motion between the sleeve 
and the core when the firearm is fired. Preferably, at least one outer 
threaded hole 54 is formed in the sleeve near its rear end 51 as 
illustrated in FIG. 1. At least one threaded hole 44 is also formed in the 
elongated cylindrical portion 36 of the core, adjacent to the shoulder. 
The outer threaded hole extends completely through the thickness of the 
outer longitudinal wall, while the inner threaded hole extends only 
partially through the thickness of the inner longitudinal wall. The inner 
and outer threaded holes are located so that they are necessarily aligned 
with each other when the sleeve is fitted over the core and the inner and 
outer openings are aligned with each other. A fastener 60 such as an Allen 
screw is inserted in the outer hole and rotated until its bottom face 
abuts the bottom wall of the inner opening as best illustrated in FIG. 3. 
Additional pairs of inner and outer threaded holes for receiving fasteners 
may be formed at other positions about the circumferences of the sleeve 
and the elongated portion of the core. 
The means for preventing relative motion between the sleeve and core may 
optionally be one or more welds formed therebetween. The welds may be 
formed at the location of the interface between the sleeve and the 
shoulder of the core, or at the front end of the device around the 
interface between the elongated cylindrical portion of the core and the 
sleeve. 
The function of the recoil reducing device in accordance with the present 
invention will now be described in greater detail. The recoil reducing 
device is attached to the exteriorly threaded end of a barrel of a 
firearm. When the firearm is fired, the bullet travels through the bore of 
the barrel and exits at the discharge end of the recoil reducing device. 
The hot, high-pressure combustion gases created by the burning of the 
gunpowder of the cartridge travel through the bore of the barrel behind 
the bullet. A small portion of the gases are expelled through the 
discharge end of the recoil reducing device. The remainder of the gases 
are expelled through the radially directed inner and outer openings as a 
natural consequence of the compressed hot gases attempting to expand to 
decrease their pressure during their travel through the device. The 
present inventor has determined that the amount of gases that are expelled 
through the radial openings can be maximized by forming the inner openings 
of the core forwardly and at about a 45.degree. angle relative to the bore 
axis of the device. 
The present inventor has also determined that gas discharge through the 
radial openings can be enhanced by varying the diameter of the bore of the 
recoil reducing device along its length. More particularly, the diameter 
of the bore may include an enlarged portion 45, 45' located immediately 
forwardly of the inner female threads of the core, and of the same 
diameter as the bore of the gun barrel for the remaining forward portion 
of the bore. This bore configuration causes the combustion gases to expand 
in the enlarged portion of the bore, and consequently have a greater 
tendency to enter the radial openings and be discharged therethrough. 
With reference to FIGS. 1 and 2, after the combustion gases have passed 
through the inclined portions 46 of the inner openings, the gases, still 
traveling at a high velocity, collide with the forward wall portions 41 of 
the inner openings and the forward walls 55 of the outer openings 52. 
These collisions transfer some of the momentum of the gases to the recoil 
reducing device as a force acting along the direction of the bore axis of 
the device. This force acts in the direction opposite to the normal 
rearward recoil of the firearm caused by gases being expelled from the 
discharge end of the firearm, so as to reduce or substantially eliminate 
recoil. 
The inner openings 38' illustrated in FIG. 7 are oriented at an oblique 
angle relative to the bore axis A--A along their entire length. 
Accordingly, the combustion gases have a lesser tendency to impact with 
the forward walls 42' of the inner openings in comparison to the 
embodiment of the present invention illustrated in FIG. 2 and described 
above, and accordingly travel substantially in the direction of the inner 
openings therethrough. The gases collide with the forward walls 55' of the 
outer openings to again cause some of the momentum of the gases to be 
transferred to the device as a force acting along the direction of the 
bore axis as in the above-described embodiment. The magnitude of this 
force is slightly less than the magnitude of the force created in the 
above-described embodiment. However, in this embodiment the combustion 
gases would be expelled from the device at substantially the same angle 
relative to the bore axis, i.e., 90.degree.. Because the shooter 
experiences reduced recoil, shooting discomfort is reduced. Furthermore, 
at the same time, shooting accuracy is improved because the shooter can 
more easily maintain the firearm in the proper position during firing. 
After the combustion gases traverse the inner openings, they enter and 
travel through the outer openings in a direction substantially 
perpendicular to the bore axis, and are expelled from the device in about 
that same direction. Consequently, the gases are directed away from the 
shooter, as also is the noise associated with the combustion of the 
gunpowder. Accordingly, the shooter is exposed to less noise and the 
danger of suffering hearing damage is reduced. The remaining small portion 
of the combustion gases, noise and unburnt gunpowder travel through the 
cylindrical bore of the recoil reducing device and exit through the 
discharge end. 
Because the outer openings are oriented perpendicular to the bore axis of 
the recoil reducing device, muzzle rise is also reduced or essentially 
eliminated. Accordingly, shooting accuracy is improved yet further in 
comparison to firearms having attached thereto one of the known recoil 
reducing devices. 
In accordance with the present invention, the number and size of the inner 
and outer openings may be varied to control their total cross-sectional 
area so as to make the device compatible with firearms having a range of 
different calibers. For example, the total cross-sectional area of the 
openings would be increased for firearms of increasing caliber so as to be 
capable of expelling the increasing volume of combustion gases associated 
therewith, to acceptably reduce the increased recoil and muzzle rise 
associated with the increasing caliber firearms. The total cross-sectional 
area of the openings may be increased by increasing either the number of 
openings, or their cross-sectional diameter. 
Regarding the pattern of the openings, preferably the openings are 
uniformly located with respect to both the length and circumferences of 
the core and sleeve. Such uniform location of the openings directs the 
expelled gases radially and uniformly from the bore, and accordingly 
substantially reduces muzzle rise. As explained above, the openings may, 
however, be formed in other patterns so as to cause the gases to be 
expelled in a particular direction as illustrated in FIGS. 5-7 and as 
discussed earlier in this specification. 
The foregoing description of the preferred embodiments of the invention 
have been presented to illustrate the principles of the invention and not 
to limit the invention to the particular embodiments illustrated. It is 
intended that the scope of the invention be defined by all of the 
embodiments encompassed within the following claims, and their equivalents 
.