US2403007A

US2403007A - Recoil brake

Info

Publication number: US2403007A
Application number: US476857A
Authority: US
Inventors: Harry B Maris
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-02-23
Filing date: 1943-02-23
Publication date: 1946-07-02
Anticipated expiration: 1963-07-02

Description

H. B. MARIS July 2, 1946-.

Filed ,Feb. 23, 1945 INVENTOR. HARRY B. MARIS" FIG Patented July 2, 1946 UNITED STATES o -"icef;

= 2,403,061-Q meta nrtinnfj Harry B; Maris, Rivrdale Md. Application February 23, 1943, Sara; No. 476,857

2 3lairns.. (01. 89-14) (Granted under the act of March '3, 1883, as amended April -30, 1928; 370-0. G. 757) i This invention is a recoil brake for firearms.

It may also be termed a compensator.

It is adapted to be secured to the muzzle'of a standard firearm, and to be removable therefrom,

although it may be made an integral part of I the same.

One object of the invention is to produce a novel construction for the muzzle of a gun,' which will reduce the recoil associated with firing.

Another object of the invention is to provide a one-piece recoil brake or compensator which is easy to manufacture and of great mechanical strength, and which will increase the efiective length of the barrel of the gun.

Another object is to produce a recoil brake which will function also to eliminate the flash of the gun. i

An additional object is to produce a recoil brake which will reduce or eliminatethe sound of gunfire.

vide in a brake of the nature mentioned; for expansion and slow escape of most of the gases of an explosion, while at the same time to utilize a part of the gases to maintain pressure behind the projectile being fired.

Other objects will be apparent from a reading: of the following specification and claims. In the drawing, Figure 1 is a section taken axially through the bore of the compensator. and a portion of a rifle barrel associated therewith, Figure 2 is a section through the expansion and escape chamber of the compensator on the plane indicated by line 2-2 of Figure 1 (and indicating by the line l-! the exact plane of the section of Figure 1), Figure 3 is a perspective-view of the principal portion of the recoil brake; and

Figure 4 is a section on a plane similar tothat of Figure 2, but illustrating a modification of the invention.

mferring to the drawing, and especially to Figure 1, l represents the barrel of the gun,

which may be assumed to be a .50 machine gun. The bore of the gun is rifled, as indicated at H. The muzzle of the piece is provided with threads I2.

The recoil brake proper, I3, is securedtto thebarrel ID of the gun by means of threads cooperating with threads l2 on the gun muzzle. And,-

in departure from previous practice-which has been to make the brake bore large enough to prevent the projectile from touching the same while passing therethrough-the bore of this invention is precisely the same as the caliber of the gun to which it is attached, and it contains rifling I4 It is a further object of the invention to prowhich is to be accurately matched to the rifiing' H's-in the gun barrel. 'A set screw l5,lor. some other means,'must be: provided fonmaintainin'g the gun barrel and the compensator in proper relation as regards rifling. Passageways forming expansion chambers are The I external appearanceof these'chambers isbest illustrated provided for the escaping gases.

in Figure 3.

The internal formation of the expansion 'chame hers is shown in Figure 1. Communicating with the bore of 'thebrake are slot-like openings which" permitescape of :thel gases from thebore; Two' such openings, 2| and 22, are shown in full in Figure 1, Two others, 20 and 23, are shown in part.

Openings

24 and 25 are indicated in Figure 2. *Thezexact size of these openings will vary inversely with the length of the brake.

. Extending'radially outwardly from the slot-like openings are the expansion chambers proper of the brake; The chamber at the right of Figure l willxbezdescribed in detail. The other chambers aresimilar. P 4 In'ithebody portion of the compensator, and extending forwardly from the forward end of slot 23*:is .formed a curvedsurface '26,;the, curve of which reverses at 21 as it approaches the peripheryiof the enlarged portion of the brake. The surface 26 functions to receive the high-velocity escaping gases; and to change their direction from" forward to. rearward .and outward." The' rear. wardly directed gases impingeonra substantially fiat surface 28, and from thence, pass to the outer air. 1 The reverse. curve 21 tends to reduce the.

blast efiect on the gunnen;

Ihe vexact angle of the face or surface 28is a matter of. compromise.

on the line 22 of Fig. 1. From the standpoint of recoil elimination, it is desirable to makethis angle as great as possible, but ifit bemade much:

greater than 45, the escaping gasesjbecomera discomfort and possibly a danger to the gunner."

The shapes of the remaining sides of theexpansionchamber are determined by the vanes 30, 3|, .32, 33, 34 and 35 (see Figures 2 and-3). These vanes extend: radially outwardly from the surface of ,the brake 'borerand terminate in longitudinal edges aligning withzthe cylindrical Sexterior. surface ofthe compensator Wherebylaterally. expandingugasesescaping from the -pas-'- sageways smoothly merge at the periphery of 'the compensator. In contradistinction to some compensators, wherein the parts are formed expressly to produce a turbulent condition to aid in cooling It is shown as being about relative'to a vradial plane substantially;

in order to permit great expansion of the gases The ratio can before they reach the outer air.

be made virtually as great as desired-by increas ing the diameter of the brake; in the structure shown, 20 or 30 to 1 can readily be obtained, and this is ordinarily more than suificient. A ratio of at least 15 to 1 will in most instances .be. satisfactory.

Figure 4 illustrates a modified vane structure for the recoil brake of the invention. The curved 5 ribs or vanes 40, 4|, 42, 43, 44 and 45 provide longer paths for the hot gases before they reach theexterior. of the brake, and thus a larger tem-. perature drop. Further, they produce, or tend to produce, an eddying or turbulent condition outside of the brake; as in the form. earlier described, no turbulence is sought inside of the compensator. r

. The structure of Figure 4 has an additional useful and novel property. By proper disposition of the vanes with respect to the direction of the rifling of the firearm, the reaction of the escaping.

gases on the curved vanes is. caused to produce a moment to counteract or resist any twisting effect in the barrel resulting from the rotation of a projectile passing therethrough.

Modification of the vane construction, in accordance with Figure 4, does not require changes in the remainder of the brake.

In operation, as a bullet passes the rearward limits of openings 28, 2|, 22, 23, 24, and 25, these openings of course permit the escape of some of the gases in the barrel. The parts of the brake are so proportioned as to provide an escape for approximately three-fourths of these hot gases during the time of travel of the projectile between the openings and the forward end of the recoil brake.

The total area of the openings mentioned is approximately 2 times the area of the bore. The velocity of the escaping gases is, therefore, more than doubled, and their pressure correspondingly' reduced.

The velocity of the gases remaining in the bore of the compensator is not substantially changed, and these remaining gases, notwithstanding their reduced quantity, maintain pressure behind the bullet. This effect requires the substantially pressure-tight relation between bullet and bore which has been mentioned. The duration of the effect is dependent principally upon the size of the openings -25 and the length of the bore forward of the openings. If the elements' are correctly proportioned, it is possible to maintain a high pressure in the bore almost to the muzzle of the compensator, and yet provide, before the gases escape behind the bullet, such reduction in temperature and pressure as will virtually eliminate the sound and flash of these gases.

With respect to the main escape and expansion chambers and the gases passing therethrough, the design of the brake should take into account the following considerations. The sound of the explosion will be deadened in proportion to the length of time provided for the escape of the gases-the longer the time, the more complete the effect. Performance in this regard thus will vary inversely with the size of the openings in the bore, and directly with the diameter of the chambers. Elimination of the flash of the gun depends upon the extent to which the hot gases are cooled before mixing with the outer air, and

therefore upon the amount of expansion provided for before the gases reach outer air. In the event all powder grains are not burned when the bullet reaches the outlet openings, the time taken for the combustion products to pass through the expansion chambers is a factor.

The above description is in specific terms. It

is apparent that many changes are possible within the spirit bf the invention, and it is therefore intended not to limit myself to the exact subject matter shown and described, but instead to include all that properly falls within the scope of the appended claims.

This invention may be manufactured and/or used by or for the Government of the United States of America without the payment to me of any royalty thereon or therefor.

I claim: a

1. A recoil brake for a gun comprising a onepiece elongate body portion having a central longitudinal bore therein adapted to match the bore of the gun barrel, said bodyportion including a forward muzzle portion and an enlarged rear vent portion of cylindrical shape and provided'with passageways from the brake bore to the cylindrical exterior of said vent portion, the' material of the rear vent portion between the passageways constituting substantially streamlined vanes extending radially from said bore to the outer limit of said rear vent portion and terminating in edges longitudinally aligning with the cylindrical exterior of said enlarged rear vent portion, the forward wall for each passageway including a forwardly and outwardly curved portion for receiving explosion gases and the rear wall for each passageway being rearwardly and outwardly inclined throughout its length, said forward muzzle portion serving to increase the effective length of the gun barrel.

2. A recoil brake for a gun comprising an elongate body portion having a bore therein adapted to match the bore of the gun barrel, said body' portion including a forwardmuzzle portion and an enlarged cylindrical rear vent portion provided with radial passageways extending from the brake bore to the cylindrical exterior of the rear vent portion, the material of the body portion between the passageways constituting substantially streamlined vanes extending radially from said. bore and terminating in edges longitudinally aligning with the cylindrical exterior of the rear vent portion, the forward wall for each passageway including a forwardly and p outwardly curved portion for receiving explosion gases and a rearwardly and outwardly reversely curved portion for reducing the blast effect toward the" gunner, and the rear wall for each passageway being rearwardly and outwardly inclined throughout its length.

HARRY B. ARIs: