Device for compensating the recoil energy of small arms

A device for reducing the felt effects of recoil in firearms including at least a barrel and a frame, this assembly including a muzzle brake unattachedly disposed around the muzzle portion of a barrel wherein the barrel completely traverses the muzzle brake. The muzzle brake is provided with deflector surfaces for upwardly deflecting pressurized gases generated during the firing of a projectile. The gases are directed against the deflector surfaces through gas outlet openings formed in the portion of the barrel transversing the muzzle brake, these gas outlets aligning with the deflector surfaces. The device further includes a retention means for securely retaining the muzzle brake to the firearm frame in relation to the longitudinal axis of the barrel. Such a device allows for the use of the combustion gases for reducing the effect of recoil, while advantageously avoiding the problems associated with precision alignment of the muzzle brake and the barrel.

FIELD OF THE INVENTION 
The present invention relates to a device which is capable of compensating 
for the recoil energy associated with the firing of small arms. More 
specifically, the invention relates to a device wherein a muzzle brake 
having at least one deflector for upwardly deflecting high pressure gases 
is fitted over the barrel of a firearm which has been supplied with gas 
outlets to supply gas to the deflectors, the muzzle brake being attached 
only to the frame, and not the barrel of the firearm. 
DESCRIPTION OF THE PRIOR ART 
The attachment of a muzzle brake to the muzzle end of a firearm in order to 
compensate for recoil energy is well known in the art. These muzzle brakes 
are positioned parallel to the barrel axis and supplied with slots which 
communicate with corresponding gas vent holes drilled in the firearm 
barrel when the device is properly fitted. In order to fit these muzzle 
brakes, the muzzle end of the barrel is threaded and the brake is screwed 
on until the slots of the muzzle brake, and the holes drilled in the 
barrel, align. A set screw is provided to prevent the muzzle brake from 
unscrewing under the forces of recoil. Also known, and as shown for 
example in West German Pat. No. 3,427,854, are muzzle brakes which are fit 
to extend past the muzzle end of the barrel, negating the need for gas 
ports in the barrel itself. 
While the above-described devices allow for the reduction of muzzle blast 
which occurs when the high velocity gas generated during firing exits the 
barrel, they cannot compensate for recoil energy as the slots through 
which the gas is dissipated are small, therefore providing only a small 
deflector surface. Further, although a set screw is usually provided, 
muzzle brakes of this type often loosen due to the great forces which act 
upon them during firing. When this occurs, the slots no longer align with 
the gas discharge holes of the barrel, and thus, the effectiveness of the 
device is totally lost. 
In addition to the above, as heretofore known muzzle brakes were designed 
to attach to the barrel, and the deflector surfaces thereof were arranged 
in front of the barrel muzzle, and as described in U.S. Pat. No. 
4,715,140, a through-opening had to be provided in the device for the 
passage of the projectile. In order to insure that the gases are deflected 
upward, through the muzzle brake, the opening must approximate the inner 
diameter of the barrel. This requirement necessitates the precise 
alignment of the muzzle brake, as otherwise the projectile may contact the 
inner wall surface of the brake resulting in the deflection of the 
projectile at best, and at worst, damage to the muzzle brake and the 
barrel of the firearm. 
Other devices of this type, which attach to the muzzle end of the barrel, 
include those designed to compensate for the rotational forces generated 
by the projectile as it travels through the rifling of the barrel. These 
rotational forces can transfer to the grip of the weapon. Devices such as 
these are designed with gas openings which are asymmetrical with respect 
to the barrel axis so that the gas outlet opening is greater on one side 
of the barrel than on the other and the unequal amount of the emerging 
gases causes an antitorque motion on the firearm. Such devices, however, 
do not counteract recoil and, due to their similar designs, suffer from 
all the disadvantages associated with muzzle brakes, as described above. 
Recoil compensating devices which attach to the frame and loosely fit over 
the barrel are also known. These devices, however, only comprise a weight 
which fits over the barrel to attenuate the recoil. Such devices do not 
use gases to compensate for recoil, however, and the alignment between the 
barrel and the weight is therefore not critical. These devices are 
disadvantageous as a great amount of weight is required to counteract 
recoil, adversely affecting the balance of the firearm. 
SUMMARY OF THE INVENTION 
It is therefore an object of the invention to provide a recoil compensating 
device which employs discharge gases to reduce perceived recoil but does 
not attach directly to the barrel of the firearm, thus avoiding the 
problems associated with precision alignment. 
The invention comprises a muzzle brake unattachedly disposed around the 
muzzle portion of the firearm barrel, said barrel completely traversing 
the muzzle brake. The muzzle brake is provided with deflector surfaces for 
upwardly deflecting pressurized gases generated during the firing of a 
projectile, these gases being directed against the deflector surfaces 
through a set of gas outlet openings formed in the barrel. The device 
further comprises a retention means for solidly retaining the muzzle brake 
to the firearm frame in relation to the longitudinal axis of the barrel. 
The inventive design can be used on firearms wherein the axis of the barrel 
shifts during the firing cycle, as well as on firearms having fixed 
barrels. The large deflector surfaces of the invention insure adequate 
recoil compensation and barrel length is not limited by the device as it 
is not necessary to fit the muzzle brake at the forward end of the barrel. 
A further advantage of positioning the muzzle brake behind the muzzle end 
of the barrel is that the energy of the projectile is not reduced by the 
blast wave of gases exiting the muzzle. 
The inventive design further achieves advantages in manufacturing as 
precision machining and alignment of the muzzle brake is not critical. The 
loosening of the muzzle brake is avoided as the brake is attached to the 
frame of the firearm, which does not move during the firing cycle, and not 
to the barrel. Further, as the compensator is only loosely positioned over 
the barrel, firearms in which the barrel is removable can be disassembled 
rapidly, without special tools. 
These and other various objects and advantages of the present invention 
will become more fully apparent as the following description is read in 
conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION 
The recoil compensating device of FIGS. 1 to 4 includes a muzzle brake 2 
unattachedly disposed around the muzzle portion of the barrel 1 of the 
firearm. The lower portion of the muzzle brake is provided with a 
retaining shoe 3 designed as a downwardly directed fork. The fork prongs 
engage holding slots 4 formed in a stationary frame element 5. The frame 
element 5 is attached to a support rod 6 by pins 10, 11. The support rod 6 
preferably also acts as a spring guide for the recoil spring 8 of the 
firearm. The support rod 6 securely connects the frame element 5 to the 
firearm receiver 7. The support rod 6 is secured to the receiver 7 by a 
pin 9. Reference numeral 12 designates the breechblock of the firearm. 
The barrel 1 is provided with lateral, outwardly directed gas outlet 
openings 13, 14, the leading edges 15, 16 of which preferably extend 
slantingly forward and upward. The outer wall of the barrel 24 and the 
side walls of the muzzle brake 23 form chambers 17, 18, corresponding in 
position to the gas outlet openings 13, 14. These chambers 17, 18 are open 
only toward the top. The front walls of the chambers 17, 18 act as 
deflector surfaces 19, 20 and are inclined in the same direction as the 
leading edges 15, 16 of the gas outlet openings 13, 14. Preferably, the 
upper area of the deflector surfaces 19, 20 slant rearwardly toward the 
top to further deflect gas flow. Although the figures illustrate a two 
chamber compensator, the number of chambers can be selected arbitrarily. 
FIG. 5 illustrates the front deflector surface 19 of the chamber 17 as 
slightly offset rearwardly with respect to the leading edge 15 of the gas 
outlet opening 13 of the barrel 1, to a degree which corresponds to the 
path traveled by the barrel, as occurs in firearms wherein the rear end of 
the barrel 1 drops during the cycling of the firearm action. FIGS. 5 to 7 
illustrate this travel, as occurs in such firearms wherein the barrel 
initially retracts by a set amount, and subsequently tilts, during 
cycling. FIG. 5 shows the position of the individual parts prior to the 
firing of the shot. FIG. 6 shows the position immediately after firing the 
shot, and FIG. 7 illustrates the position of the parts when the action is 
at its rearwardmost position, with the breech open, and with the rear end 
of the barrel 1 tilting downward. In correspondence with this downward 
tilting, the muzzle brake 2 travels upwards via its fork 3 in the holding 
slot 4 without impairing the movement of the barrel 1 in any way. During 
the closing of the breech, the movements, as illustrated in FIGS. 5 to 7, 
occur in the opposite direction. 
Upon firing a shot, the projectile initially accelerates through the barrel 
1 until passing gas outlet opening 13 from which a first portion of the 
combustion gas escapes and is deflected along the deflector surfaces 15 
and 19 as shown in broken lines by the arrow P. A similar gas discharge 
occurs via gas outlet opening 14 as shown by arrow Q. The gas is deflected 
upwardly and thus compensates recoil and the impact energy of the gas upon 
the atmosphere. The remaining propellant gas emerges from the barrel at 
its forward end as indicated by arrow S. 
While the inventive design is applicable for all types of small arms, both 
those with fixed barrels and those wherein the barrel drops during cycling 
of the action, the deflection of the gases is attained in the same manner. 
However, in firearms with rigid barrels, it should be noted that no 
relative motion between the barrel and muzzle brake occurs and therefore, 
the respective surfaces of the gas outlet openings and the chambers must 
always be aligned adjacent to each other. 
While preferred embodiments have been shown and described, various 
modifications and substitutions may be made thereto without departing from 
the spirit and scope of the invention. Accordingly, it will be understood 
that the present invention is not to be limited except by the character of 
the claims appended hereto.