Ammunition and explosives – Cartridges – Projectile structure
Reexamination Certificate
1999-05-03
2001-07-10
Tudor, Harold J. (Department: 3641)
Ammunition and explosives
Cartridges
Projectile structure
C102S449000, C102S506000
Reexamination Certificate
active
06257147
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method, apparatus and system for suppression of over-penetration in small arms.
More particularly, the present invention relates to suppression of spreading in shot load projectiles fired from weapons such as shotguns.
In a further and more specific aspect, the instant invention concerns a method and apparatus for suppressing muzzle blast and/or muzzle crack in weapons deploying shot loads.
2. Prior Art
In operation of small arms, it is known that it may be desirable to suppress muzzle jump and/or recoil. Muzzle jump and recoil both stem from the inherent physics of rapidly propelling a mass, via deflagration of a propellant, from the chamber of the through the barrel and out of the muzzle, through Sir Isaac Newton's law of physics that states “For every action, there shall be an equal and opposite reaction”. These phenomena may be undesirable because they tend to (i) reduce accuracy of the shot and (ii) fatigue the person operating the weapon.
One approach to reducing perceived recoil and/or muzzle jump phenomena as well as to increase accuracy is to provide one or more, and usually many, ports exiting from near the muzzle end of the weapon. This has the effects of distributing the escape of burning gases over time, reducing the temporal impact of the recoil, and of re-directing the dispersal of the gasses in chosen directions, reducing and/or directing the impact of the recoil along the long axis of the weapon. However, this does relatively little towards reducing the muzzle blast and/or muzzle crack resulting from discharge of the weapon.
These types of adaptations are marketed by, among other gunsmiths, Pro-port® Limited (41302 Executive Drive, Harrison Township, Mich. 48045-1306, telephone number (810) 469-7323). Another type of weapon modification is the provision of chokes on shotguns. All of these have the above-noted advantages but also include risk of damage to the weapon when they are mishandled, because they tend to weaken the barrel of the weapon in the region in which they are installed.
For example, when using a shotgun equipped with ports and a choke, it is generally undesirable to pass a deer slug through the weapon because the normal function of the choke is to compress the projectiles. Deer slugs tend to be relatively incompressible and this likely will result in undue stress being developed in the region of the choke and ports, which may in turn result in fracture of the barrel at the muzzle end.
Muzzle blast is a loud noise or bang that generally accompanies the discharge of a firearm. A variety of techniques have been developed to redirect or eliminate muzzle blast for some types of small arms. These devices generally fall into two categories, known as (i) muzzle brakes and flash hiders and (ii) suppressors or silencers.
Flash hiders tend to constrict the path of the escaping, burning gasses, reducing the field of view from which the muzzle flash is readily visible. Muzzle brakes may be employed to counter muzzle climb or muzzle jump, e.g., the famous Cutts compensator employed on the Thompson submachine gun, amongst other weapons. Flash hiders and muzzle brakes do relatively little to ameliorate noise upon discharge of a weapon.
Sound suppressors also modify the path of the escaping gasses, but do so in such as way as to temporally disperse the escape of burnt and/or burning gasses from the muzzle. This has the effect of dispersing over time what otherwise would be a loud bang, in order to provide a much softer noise.
Usually, this requires a series of chambers distributed in a canister that is adapted to be secured to the muzzle of the weapon. The chambers are coupled to the barrel in order to allow deflagrating and burnt gaseous propellants to escape from the barrel into the chambers. The gasses then exhaust from the chambers through the barrel, but they are dispersed and delayed and also are engaged in much more turbulent flow. The objective is to silence the escape of burning or burnt gasses from the muzzle of the weapon. These types of devices often work rather well for small arms that discharge a single projectile such as a bullet.
However, even with a suppressor that is adapted to reduce muzzle blast to levels that would not otherwise require hearing protection devices for operation of the weapon, another phenomenon gives rise to substantial noise upon discharge of weapons employing supersonic ammunition, i.e., ammunition that will result in a projectile traveling at a speed greater than Mach 1 when the weapon is discharged. When the load, projectile or shot is traveling at a speed greater than the speed of sound in air (i.e., 1100
+
feet per second) as the load exits from the muzzle of the weapon, the load or projectile also carries with it and radiates a shock wave or sonic boom. This phenomenon is known as “muzzle crack” and it may also result in substantial noise levels.
Muzzle crack and muzzle blast each generally serve to render operation of a weapon an event likely to be noticed by the person operating the weapon, any persons who are cooperating with the person operating the weapon and any persons who simply happen to be in the vicinity, providing that these various persons are not deaf. Moreover, these events are also likely to suggest to the person operating the weapon and persons cooperating therewith that hearing protection may well be a good idea for avoiding deafness.
Hearing protection tends to inhibit conversation and may increase likelihood of ear infection if the hearing protection extends into the ear canal. Hearing protection devices may also inhibit wearing of a hat for obviating unwanted solar illumination or glare in target shooting. Hearing protection may additionally be a very poor idea in certain types of Special Weapons operations wherein peace officers are attempting to control inherently dangerous situations.
In these types of settings, it is desirable for the peace officer to not only make as little noise as possible in the course of resolving each element of the problem. It is also strongly desirable that the peace officer be able to tell what is going on in the immediate vicinity. Being able to hear sounds of movement may well be critical to the peace officer's continued ability to function effectively. Additionally, in these types of settings, it may well be that accuracy and shot placement not only are important in the short range or over a short distance, it may be extremely desirable to reduce the likelihood of a load or projectile(s) finding an inadvertent target at a greater distance, a problem known as “over penetration”.
For example, in attempting to apprehend or neutralize an “armed and dangerous” band of thugs in a crowded apartment building, it is generally undesirable to employ projectiles having lethal capacity after penetration of a multiplicity of walls. These settings call out for a weapon that is not only able to be operated relatively silently and which is also intended to be deadly or at least capable of disabling a human target at short range, but which also is at least less likely to have a long range killing impact or potential. A suppressed shotgun deploying a subsonic shot load would be ideal for many types of Special Weapons operations.
A feature common to suppressed weapons is a means for deploying a projectile without adversely affecting the ability of the operator to place the shot and without suffering the deleterious effects of muzzle blast, muzzle crack, muzzle jump and recoil. Because suppressors include chambers coupled to a length of barrel, they tend to be larger in diameter than the barrel. This tends to interfere with use of sights that are normally coupled to the barrel to enable accurate placement of the shot. Additionally, the added mass and bulk of the suppressor may interfere with rapidly aiming at a specific target. These effects are generally undesirable.
Accordingly, it is desirable, particularly with respect to weapons intended to deploy a shot load, to be able to suppress m
Goltry Michael W.
Parsons Robert A.
Parsons & Goltry
Tudor Harold J.
LandOfFree
Frangible shotshell does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Frangible shotshell, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Frangible shotshell will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2436939