BULLET

Abstract: The invention relates to a bullet having a tapered nose (14a) and a cylindrical base (12a). The base is provided with an annular groove (17) having a diameter less than the bore diameter of the barrel of the gun from which it is fired to reduce the force required to move the bullet through the barrel to increase the muzzle velocity and kinetic energy of the bullet.

Description: BULLET This invention relates to bullets generally, and in particular to small arms bullets in calibers from .224 inch to .500 inch of the bonded core, solid shank, soft nose, controlled expansion type used for hunting, self-defense, military, and law enforcement purposes. Priority is claimed based on U.S. Application Serial No. 09/ 013,962 filed January 27, 1998. This invention is an improvement on the bullets described in U.S. Patent No. 5,621 , 186 dated April 15, 1997, U.S. Patent No. 5,641 ,937 dated June 24, 1997, and U.S. Patent No. 4,879,953 dated November 14, 1989. Present day bullets are assembled with a cartridge filled with a powder charge. When fired, the bullet travels through a gun barrel having spiral grooves with spiral lands between the grooves. The diameter of the bullet is equal to or slightly less than the diameter of the grooves but greater than the diameter of the lands so that spiral grooves are formed in the cylindrical section of the bullet that follow the spiral and cause the bullet to be rotating on its longitudinal axis when it leaves the barrel. This improves the accuracy of the gun. Thus, the pressure exerted on the bullet by the burning powder of the cartridge accelerates the bullet as it travels through the barrel and also provides the force required for the lands to cut spiral grooves in the bullet causing it to be spinning on its longitudinal axis as it leaves the barrel. It is an object and feature of this invention to reduce the force required to cut the spiral grooves and thereby increase the muzzle velocity of the bullet, which also increases the kinetic energy of the bullet without reducing the rate at which the bullet spins. It is a further object of this invention to provide a controlled expansion bullet that will obtain higher muzzle velocities with the same pounds per square inch pressures provided by the cartridge that are established by the American National Standards Institute and published by Sporting Arms and Ammunition Manufacturers, Inc. These standards are generally known in the ammunition industry as "ANSI/SAMMI." It is also an object of this invention to substantially reduce the length of the portion of the outer surface of the bullet that is in engagement with the lands and grooves of the barrel as the bullet travels through the barrel and thus increase the amount of the energy produced by the burning powder that is available to accelerate the bullet as it travels through the barrel. The twist of the grooves in the barrel of a firearm produces the spin of the bullet and the twist ranges from one turn in 9.5 inches to as slow as one turn in 20 inches. The number of rifling lands in a conventional barrel normally ranges from as low as four to as high as six. The height of the rifling lands ranges from .0025 inch to .007 inch. It is a further object and feature of this invention to provide a bullet having a circumferential groove in the base shank section of the bullet having a diameter less than the diameter of the lands between the grooves to decrease the force required to force the bullet through the barrel and thereby increase the muzzle velocity of the bullet. Another object of this invention is to provide a uniform and equal friction reduction on all weights of bullets of the same diameter. These and other objects, advantages, and features of this invention will be obvious to those skilled in the art from a consideration of this specification including the attached drawing and appended claims. In the Drawings: FIG. 1 is a view partly in section and partly in elevation of a bottleneck cartridge assembled with a typical prior art bullet. FIG. 2 is a view partly in section and partly in elevation of a bottleneck cartridge assembled with a bullet shaped in accordance with this invention. FIG. 3 is a view partly in section and partly in elevation of a cylindrical cartridge assembled with a prior art bullet. FIG. 4 is a view partly in section and partly in elevation of a cylindrical cartridge assembled with the bullet of this invention. FIG. 5 is a side view of a fired prior art bullet showing the grooves formed in the bullet by the rifling in the gun barrel. FIG. 6 is a side view of a fired bullet of this invention showing the grooves formed in the bullet by the rifling of the gun barrel. FIG. 7A-D show how the weight of a bullet of the same caliber is increased by adding metal to the rear of the bullet. As shown in FIG. 1 , when cartridge 16 is positioned in the chamber of a gun, the nose 14 of the bullet of the cartridge usually extends into the barrel 18 and is at least partly in engagement with the spiral lands 20 between spiral grooves 22 in the barrel since cylindrical portion 10 of the bullet has a diameter equal to or slightly less than the diameter of the grooves. This insures that the grooves will impart the desired rotation to the bullet as it travels through the barrel. At the same time, the lands cut grooves in the portion of the bullet having a diameter larger than that of the lands. The bullet of this invention is shown in FIG. 2. It is the same as the bullet of FIG. 1 except for a force reducing band (FRB) 17 in cylindrical portion 12a of the bullet. FIGS. 3 and 4 are the same as FIGS. 1 and 2 except portions Gl , G2, B and C are identified. These areas of the bullet appear below in the comparison tables. FIG. 5 demonstrates the grooves 24 cut in a prior art bullet by the action of the rifling lands as the bullet passes through the barrel. FIG. 6 demonstrates that, by virtue of the annular groove (force reducing band: FRB) of the present invention, less surface area on the cylindrical base of the bullet surface is exposed to the barrel rifling lands with corresponding reduction in the amount of metal that is displaced through the cutting of grooves 24 on the bullet as it passes through the barrel. It can be readily appreciated by one skilled in the art that this will decrease the force required to force the bullet through the barrel. FIG.7A-D demonstrate four embodiments in which an annular groove (force reducing band; FRD) of the present invention is incorporated in bullets of different weights (shown ranging from, for example, 150 grains on the FIG.7A to 200 grains on Fig. 7D) within the same caliber, here for example, a .308 caliber bullet. It can be readily appreciated by one skilled in the art that an annular groove of the subject invention can be effectively placed in various locations on the shank of bullets with different desired conformations. Set out below in Schedule A are the dimensions of thirteen bullets of varying calibers modified in accordance with this invention. In each case, the difference between the groove diameter and the bore diameter is an approximation of the metal that is displaced as the lands cut grooves in the cylindrical portion of the bullet. The FRB or Force Reducing Band has a diameter less than the bore diameter so no metal is displaced over that portion of the cylindrical portion of the bullet, which reduces substantially the force required to move the bullet through the barrel of the gun. As a consequence, the muzzle velocity of the bullet is increased substantially, which, in turn, increases the kinetic energy imparted to the bullet. A comparison of the muzzle velocity and kinetic energy between "standard" bullets, i.e., bullets without a FRB and bullets with FRB is indicated below in Schedule B. Schedule C below is a chart of 13 different gun barrels for 13 different caliber bullets comparing the width of the lands in each barrel to the circumference of the bullet of the same caliber. Schedule D below indicates the reduction in the length of a standard bullet in engagement with the lands and grooves compared to the bullet of this invention. The average reduction is about 58%. Schedule E indicates the increase in muzzle velocity and kinetic energy of bullets of this invention compared with the standard bullets of the same caliber. Schedule F makes the same comparison as Schedule C except for pistols instead of rifles. From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus and structure. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. Because many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. SCHEDULE A METHOD OF REDUCTION IN LENGTH OF BULLET AT GROOVE DIAMETER WITH FRICTION REDUCTION BAND (FRB) THE BOTTLENECK TYPE CARTRIDGE CA8E8 AND BARREL DIMENSIONS ARE BASED ON ANSI 18AMMI SPECIFICATIONS. A B C D E F G H CARTRIDGE TYPE, BULLET WOT., Bullet Bullet Bullet Standard Cartridge Bullet Bullet Lglh. Reduction GROOVE DM., BORE OIA., AND Overall Ogive Chamfer Bullet Lglh. Neck Lglh. at Groove % D Col. FRACTION REDUCTION BAND OIA Lglh Lfllh Lqth Groove Dla. Lglh FRB Dla. Ola. Lath 223 Rem. Bullet wgl. 55 grt. Groove dla..224 bor* dla .21* 730 .382 .033 .313 .24/ .130 .183 427. FRB dla. .217 243 Win. Bullet gt. 100 grt. Groove dla..243 bore dla..237 1.0S0 .083 .039 .200 .180 .ISO 53% FRB dla..2338 25/00 Rent. Bullet wgl IIS grt. Groove dla..23? bore dla..230 1.142 .000 .039 250 .25? FRB dla. .248 204 Win. Mag Bullet wgL 140 grt. Groove dla..2(5 bore dla..250 1.202 .015 .035 .275 .337 45% FRB dla. .254 270 Win. Bullet wgl. 140 grt. Groove dla. .277 bore dla. .270 1.158 .022 .571 .305 .300 .200 52% FRB dla. .208 7mm Rem. Mag. Bullet wgt 100 grt. Groove dla..284 bore dla. .270 1.135 .500 .035 .240 40% FRB dla. .274 30/00 Sprg. Bullet wgl 1(5 grt. Groove dla..308 bore dla. .300 1.147 .033 .486 .380 .224 261 54% FRB dla..208 8mm Rem. Mag. Bullet wgl 225 git. Groove dla..323 bore dla..317 1.330 .050 .040 .040 .320 .280 .3(0 44% FRB dla. .315 338 Win. Mag. Bullet wgt 225 grt. Groove dla..338 bore dla. .330 1.324 .070 .040 .005 .331 .280 .325 40% FRB dla.328 35 Whelen Bullet wgl. 225 grt. Groove dla.357 bore dla..340 1.175 .543 .040 .502 .402 .325 .2(7 54% FRB dla..34$ 4/O tllUo Bullel wi|t 500 gis Groove dla 474 bore dla .458 .045 .647 .765 400 247 (1% FRB dla 454 AVERAGE FRICTION REDUCTION 40% SCHEDULE B INCREASE IN VELOCITY AND MUZZLE ENERGY OF BULLETS IN BOTTLENECK CARTRIDGES THE CARTRIDGES, STANDARD VELOCITY, STANDARD ENERGY, AND MAXIMUM AVERAGE PRESSURES ARE BASED ON ANSI / SAMMI SPECIFICATIONS. B C Standard Standard Energy S.A.M.M.I. 7% 14% Velocity Foot Max. Avg. Increased Increased Ft. Per Sec Pound Pressure Velocity Ene y 223 Rem. 3240 1280 52,000 3466 1459 243 Win. 2960 1950 60,000 3167 2226 25/06 Rem. 2990 2285 63,000 3199 2613 264 Win. 3030 2854 68,100 3267 3267 270 Win. 2940 2685 69,100 3145 3074 Os 7mm Rem. Mag. 2940 3070 64,800 3145 3513 30-06 Sprg. 2800 2872 60,000 2996 3288 338 Win. 2800 3915 68,100 2996 4484 35 Whelen 2500 3120 52,000 cup 2674 3574 375 H & H 2530 4265 66,000 2707 4880 416 Rem. 2400 5115 69,100 2568 5856 458 Win. 2090 4850 53,000 cup 2236 5550 470 Nitro 2150 5130 35,000 cup 2300 5872 S.A.M.M.I recognizes two methods of measuring centerfire rifle pressures - The older Copper Crusher System and the modern Piezoelectric Transducer System. SCHEDULE C THE BOTTLENECK CARTRIDGES AND INTERNAL BARREL CHARACTERISTICS ARE BASED ON ANSI / SAMMI SPECIFICATIONS. A B C D E F G H I Twist Number Bullet Width Width Depth Width Width % of one turn of circumof of of of of col. G to in inches Grooves ference Grooves Groove Groove Lands Land col. C 223 Rem. 14 6 .703 .480 .080 .0025 .223 .037 .317 243 Win. 10 6 .763 .408 .068 .003 .354 .059 .464 25/06 Rem. 10 6 .807 .576 .096 .0035 .231 .0385 .286 264 Win. 9 6 829 .540 .090 .004 .289 .048 .349 270 Win. 10 4 .870 640 .160 .0035 .230 .0575 .264 7mm Rem. 9.5 6 892 .660 .110 .0035 .232 .038 .260 30-06 Sprg. 10 4 968 .706 .1767 .004 .262 .065 .270 8mm Mag. 10 6 1.045 .732 .122 .004 .313 .052 .427 338 Win. 10 6 1.062 .660 .110 .004 .402 .067 .473 35 Whelen 16 6 1.124 .780 .130 .004 .344 .057 .306 375 H & H 12 6 1.178 .690 .115 .006 .488 .081 .414 416 Rem. 14 6 1.307 .768 .168 .004 .539 .089 .413 458 Win. 14 6 1.439 .900 .150 .004 .539 .090 .374 470 Nitro 14 6 1.489 .960 .160 .007 .529 .088 .355 SCHEDULE D METHOD OF REDUCTION IN LENGTH OF BULLET AT GROOVE DIAMETER WITH FRICTION REDUCTION BAND (FRB) THE CYLINDRICAL OR TAPERED WALL CARTRIDGE CASI CASES AND BARREL DIMENSIONS ARE BASED ON ANSI / SAMMI SPECIFICATIONS I A B C D E F G H CARTRIDGES TYPE BULLET WGT. Bullet Standard Bullet Bullet GROOVE DIA., BORE DIA., AND Bullet Ogive Bullet Bullet Lgth. Cartridge at Dla. at Groove Reduction FRICTION REDUCTION BAND OAL Lgth. Chamfer Groove Dla. Neck FRB dia. % D Col. 9mm Luger Bullet wgt. 124 grs. Groove dia. .355 bore dia. .346 .570 .250 .035 .285 .185 .100 65% FRB dia. .342 38 Special Bullet wgt. 129 grs. Groove dla. .355 bore dia. .346 .600 .320 .035 .245 .145 .100 59% FRB dla. .342 357 Magnum Bullet wgt. 158 grs. Groove dia. .355 bore dla. .346 .675 .300 .035 .340 -0- .200 .140 59% FRB dia. .342 10mm Auto Bullet wgt. 180 grs. Groove dia. .400 bore dia. . 390 .600 .300 .035 .265 -0- .165 .100 62% FRB dia. .386 40 S & W Bullet wgt. 165 grs. Groove dla. .400 bore dia. .390 .585 .340 .035 .210 -0- .110 .100 52% FRB dla. .386 44 Rem Mag Bullet wgt. 240 grs. Groove dia. .429 bore dia. .417 .750 .350 .035 .365 -0- .200 .165 55% FRB dia. .413 45 Auto Bullet wgt. 230 grs. Groove dia. .450 bore dia. .442 .675 .283 .035 .357 -0- .180 .170 50% FRB dia. .438 45 Colt Bullet wgt. 225 grs. Groove dia. .450 bore dia. .442 .600 .283 .035 .282 -0- .175 .107 62% FRB dla. .438 .458 Win Mag Bullet wgt. 500 grs. Groove dia. .458 bore dla. .450 1.379 .650 .045 .684 -0- .400 .284 58% FRB dia. .446 SCHEDULE E INCREASE IN VELOCITY AND MUZZLE ENERGY OF BULLETS IN CYLINDRICAL OR TAPERED WALL CARTRIDGE CASES. THE CARTRIDGES, STANDARD VELOCITY, STANDARD ENERGY, AND MAXIMUM AVERAGE PRESSURESARE BASED ON ANSI / SAMMI SPECIFICATIONS. A B C D E F Standard Standard SAMMI 7% 14% Bullet Velocity Energy Max. Avg. Increased Increased Wgt. Ft. Per Sec. Ft. Pounds P.S.I. Velocity Energy 9mm Luger Bullet 124 1120 345 35,000 1200 393 38 Special 129 950 255 20,000 1016 291 357 Mag. 158 1240 535 45,000 1327 610 10mm Auto 180 1030 425 37,500 1102 485 40 S & W 155 1195 445 35,000 1278 507 44 Rem. Mag. 240 1180 740 36,000 1263 844 45 Auto 230 850 370 21,000 909 422 45 Colt 255 900 405 14,000 965 462 458 Win. Mag. 500 2090 4850 53,000 2236 5529 SCHEDULE F THE CYLINDRICAL AND TAPERED WALL CARTRIDGES AND INTERNAL BARREL CHARACTERISTICS ARE BASED ON ANSI / SAMMI SPECIFICATIONS. A B C D E F G H I Twist one Number Bullet Width Width Depth Width Width Lands % turn in of circumof of of of of of inches grooves ference grooves groove groove lands land circumference 9mm Luger 10 6 1.115 .600 .100 .0045 .515 .085 .46 38 Special 18.75 6 1.124 .630 .105 .005 .494 .082 .39 357 Magnum 18.75 6 1.124 .630 .105 .0045 .494 .082 .39 10mm Auto 16 6 1.258 .720 .120 .0052 .538 .089 .43 40 S & W 16 6 1.258 .720 .120 .0052 .538 .089 .43 44 Rem Mag 20 6 1.357 .642 .107 .006 .715 .119 .526 45 Auto 16 6 1.420 .882 .147 .004 .882 .147 .500 45 Colt 16 6 1.432 .936 .156 .004 .492 .082 .343 458 Win Mag 14 6 1.439 .900 .150 .004 .539 .090 .374

Claims: CLAIMS WHAT IS CLAIMED IS: 1. In a bullet assembled with a cartridge containing a powder charge, the bullet having a tapered nose and a cylindrical base having a diameter such that rifling in a barrel from which the bullet is fired will cut spiral grooves in the base of the bullet as the bullet is accelerated through the barrel when the explosive charge of the powder in the cartridge is detonated, the improvement comDrising an annular groove in the cylindrical base of the bullet having a diameter less than a bore diameter of the barrel to reduce the force required to move the bullet through the barrel to increase the muzzle velocity of the bullet. 2. The bullet of claim 1 wherein said annular groove increases the muzzle velocity about 7% and increases the kinetic energy of the bullet about 14% over that of a standard bullet.

Inventors: CARTER HERMAN L, CARTER, HERMAN, L.
Applicants: TROPHY BONDED BULLETS INC, TROPHY BONDED BULLETS, INC.
Application year: 1999
Main classification: F42B14
IPC codes: F42B5, F42B12, F42B30