US45898A - Improvement in rifling breech-loading fire-arms - Google Patents

Improvement in rifling breech-loading fire-arms Download PDF

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US45898A
US45898A US45898DA US45898A US 45898 A US45898 A US 45898A US 45898D A US45898D A US 45898DA US 45898 A US45898 A US 45898A
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bore
balls
ball
breech
gun
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A21/00Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
    • F41A21/16Barrels or gun tubes characterised by the shape of the bore
    • F41A21/18Grooves-Rifling
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A21/00Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
    • F41A21/12Cartridge chambers; Chamber liners
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A21/00Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
    • F41A21/48Barrel mounting means, e.g. releasable mountings for replaceable barrels
    • F41A21/482Barrel mounting means, e.g. releasable mountings for replaceable barrels using continuous threads on the barrel
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00Breech mechanisms, e.g. locks
    • F41A3/02Block action, i.e. the main breech opening movement being transverse to the barrel axis
    • F41A3/04Block action, i.e. the main breech opening movement being transverse to the barrel axis with pivoting breech-block
    • F41A3/08Block action, i.e. the main breech opening movement being transverse to the barrel axis with pivoting breech-block carrying a rotably mounted obturating plug of the screw-thread or the interrupted-thread type
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41CSMALLARMS, e.g. PISTOLS, RIFLES; ACCESSORIES THEREFOR
    • F41C9/00Other smallarms, e.g. hidden smallarms or smallarms specially adapted for underwater use
    • F41C9/08Muzzle-loading smallarms; Smallarms with flintlock mechanisms; Accessories therefor

Definitions

  • Fig. 6 is a side elevation, in part sectional, of the cartridge.
  • Figs. 7 and 8 are elevations of balls used in the cartridge.
  • This invention relates to-an improvement of the counter-bore or cartridge-receiving chamber in the rear end ofthe barrel.
  • the rear portion ofthe riiied bore terminates in an enlarged smooth cylindrical chamber called the connter-bore.77
  • the ammunition or cartridge is inserted into .the counter-bore, which extends from the rear extremity of the barrel up to the junction with it of the grooved or ritled bore.
  • the front end of the counterbore is usually contracted into a smooth cylindrical incline or shoulder.
  • the surface of the ball When the enlarged ball is driven forward by the ignition of the powder into the riiled bore the surface of the ball must necessarily be compressed or channeled, so as to exactly tit or correspond to the form of the ried bore.
  • the resistance of the ball when thus suddenly' subjected to compression is enormous. The duration and degree of this resistance will, in balls of' a given size, be proportionate to the surface length ofthe balls.
  • Another objection to these arms is that the balls must be composed of very soft metal, so that their compression into the riiied bore may be ei'eoted with the least resistance. The harder the metal ofthe balls the greater will be their resistance when they are driven against the incline or shoulder ofthe counter-bore and compressed into the grooves of the ritied bore.
  • the necessary softness ot' the metal composing the balls is such that by the resistance occasioned by compressing them into the grooves ,and by the force of the gas arising from the ignition of the powder the balls are upset and forced one into the other, and their distinctive shape is thus lost. Theyemerge from the gun in the form of a disproportionate plug, and their accuracy of flight is destroyed. In addition to this, by the upsetting and jamming together of the balls the interior of the rified bore of the gun becomes badly leaded.
  • myinvention consistsin grooving or ritli'n g the interior surface of the chargeehamber or counter-bore with grooves which Another obcorrespond to and unite with those of the barrel and have the same twist as the grooves of the barrel.
  • A. represents the barrel of the gun, made, as shown in Fig. l or as in Fig. 2, in the usual manner and of thc usual materials.
  • a is the bore of the gun, which is made of sexagonal or other suitable form, with grooves b, as shown, which extend or are continued within and parallel with the inner surface of the incline c and counter-bore or charge-chamber d, substantially as shown.
  • a recess. c, at the rear of the counter-bore receives the cylindrical cap of the cartridge B, as shown in Fig. 2.
  • My improvement is not confined to any particular species of grooving or feathering, nor' to any particular degree of twist thereof, nor to any particular sizeorspecies of breech-loading guns.
  • My improvement may be employed in connection with almost every known species of riiied grooving or feathering; and it may be employed in all kinds and in all sizes of breechloading guns. 4
  • I employ a novel species of fixed ammunition.
  • a cartridge, B the shell or case of which is so made or prepared that its exterior will correspond with the shape of the interior of the riiied counter-bore and snugly iit therein.
  • the exterior of the cartridge-case therefore has the same twist as the grooves of the counter-bore.
  • the interior form ofthe cartridge B also corresponds with its exterior.
  • Kthe cartridge case corresponds in form and size very closely to that of the riiied bore of the barrel.
  • tridge-case thus made receives and holds one or more balls, either rounded or elongated, which have had their surfaces previously prepared to correspond with and exactly it into the rilied grooves of the bore of the gun.
  • balls either rounded or elongated, which have had their surfaces previously prepared to correspond with and exactly it into the rilied grooves of the bore of the gun.
  • I prepare the balls by using a section of a ritied barrel as a die or mold, through which I force the metal by means of a suitable plunger. The exact fitting of the balls into the riiied grooves ofthe gun is thus secured. I also prepare the cartridge-shells by using a section of the counter-borel as a die with a plunger ofthe form and size of the rilied bore.
  • the exterior of the elongated balls may be covered with patches, as shown at K, before the balls are placed within the cartridge-shells.
  • the die by which they are to be prepared must be made
  • the car-A smaller thanv the bore of the gun to allow for the thickness of the patch.
  • the shells of the cartridge may be composed of metal or fibrous substance, or both combined; or anyothersuitable material that can be pressed, cast, or made into the form described may be employed.
  • My invention greatly facilitates the employment of cartridges containing a series of balls which may be simultaneously discharged.
  • Two kinds of ammunition may be used in connection with my gun-namely, single-ball cartridges, as shown in Fig. 6, for long-ran firing, or three-balled cartridges, as Asho Fig. 3, for short-range or volley firing.
  • Another important advantage ot' my improvement is that by the simple act of introducing the cartridge into the counter-bore several balls may be simultaneously and accurately litted into position in line with the grooves of the gun, ready for rino. Thus the flight of the balls will be accurate, whether a single heavy ball for long-range firing be used, or two or more lighter balls for shortrange or volley tiring be employed.
  • the soldier when in action, may penetratedily change the character of his amunition to suit the constantlyvarying nature ot' his service-using the long or short range cartridges as circumstances require.

Description

H. BERDAN. Ri'fl'ng. N0. 45,898. Patented Jan. 10, 186,5.
Hmmm.
N. PEYERS, PHUTDMTHOGRAPHER, WASHINGTON, D C4 UNITED STATES PATENT OFFICEo HIRAM BERDAN, OF NEW YORK, N. Y., ASSIGNOR TO LEVI I. MORTON,
TRUSTEE OF HIRAM BERDAN, ABIA A. SELOVER, AND WVM. B. BENSON,
OF SAME PLACE.
IMPROVEMENT IN RIFLING BREECH-LOADING FIRE-ARMS.
Speeiiication forming part of Letters Patent No. 45,898, dated January 10, 1865.
To all whom 'zit may concern:
Be it known that I, HIRAM BERDAN, ofthe cit-y, county, and State of New York, have in- Avented a new and useful Improvement in Breech-Loadin g Rifled Fire-Arms and Gannon 5 an elevation ofthe lnuzzle of the same barrel.
Fig. 6 is a side elevation, in part sectional, of the cartridge. Figs. 7 and 8 are elevations of balls used in the cartridge.
Similar letters of reference indicate corresponding parts. v
This invention relates to-an improvement of the counter-bore or cartridge-receiving chamber in the rear end ofthe barrel. In the construction of the barrels of theordinary breech-loading lire-arms the rear portion ofthe riiied bore terminates in an enlarged smooth cylindrical chamber called the connter-bore.77 The ammunition or cartridge is inserted into .the counter-bore, which extends from the rear extremity of the barrel up to the junction with it of the grooved or ritled bore. As the counter-bore is larger in diameter than the riiled bore, the front end of the counterbore is usually contracted into a smooth cylindrical incline or shoulder. In guns ot' this character it is common to employ whatis known as xed ammunitionl-to wit, a cartridge havin ga metallic shell loaded with powder and ball. Sometimes, however, a paper cartridge is used. The cartridge is inserted into the counterbore, the ylengthof which should be such' that if an elongated ball is employed the front end of the ball will reach, or nearly reach, the incline and the point of the ball will be dia ted toward the center of the riiled bore. 1n al form the balls are cylindrical, and they are necessarily made ot' larger diameter than the riiied bore'of the gun, so that when iiijed the balls will wholly ll up the riiied grooves. When the enlarged ball is driven forward by the ignition of the powder into the riiled bore the surface of the ball must necessarily be compressed or channeled, so as to exactly tit or correspond to the form of the ried bore. The resistance of the ball when thus suddenly' subjected to compression is enormous. The duration and degree of this resistance will, in balls of' a given size, be proportionate to the surface length ofthe balls. Another objection to these arms is that the balls must be composed of very soft metal, so that their compression into the riiied bore may be ei'eoted with the least resistance. The harder the metal ofthe balls the greater will be their resistance when they are driven against the incline or shoulder ofthe counter-bore and compressed into the grooves of the ritied bore.
In muzzle-loading riiied guns it is common to cover the exterior ofthe ball with a patch, which serves to reduce the resistance of the ball, and also prevents the leading of the bore when soft-metal balls are used 5 but in the ordinary breech-loading guns it is impossible to employ a patch, because the surface of the ball must be compressed or channeled so as to t into and fill the ritled grooves. jection to the ordinary breech-loading ritled lire-arms is the difticultyof simultaneously liring more than one ball. When we attempt to use more than one ball in such arms the necessary softness ot' the metal composing the balls is such that by the resistance occasioned by compressing them into the grooves ,and by the force of the gas arising from the ignition of the powder the balls are upset and forced one into the other, and their distinctive shape is thus lost. Theyemerge from the gun in the form of a disproportionate plug, and their accuracy of flight is destroyed. In addition to this, by the upsetting and jamming together of the balls the interior of the rified bore of the gun becomes badly leaded.
The nature of myinvention consistsin grooving or ritli'n g the interior surface of the chargeehamber or counter-bore with grooves which Another obcorrespond to and unite with those of the barrel and have the same twist as the grooves of the barrel.
Referring to the drawings, A. represents the barrel of the gun, made, as shown in Fig. l or as in Fig. 2, in the usual manner and of thc usual materials.
a is the bore of the gun, which is made of sexagonal or other suitable form, with grooves b, as shown, which extend or are continued within and parallel with the inner surface of the incline c and counter-bore or charge-chamber d, substantially as shown. A recess. c, at the rear of the counter-bore receives the cylindrical cap of the cartridge B, as shown in Fig. 2.
My improvement is not confined to any particular species of grooving or feathering, nor' to any particular degree of twist thereof, nor to any particular sizeorspecies of breech-loading guns.
My improvement may be employed in connection with almost every known species of riiied grooving or feathering; and it may be employed in all kinds and in all sizes of breechloading guns. 4
1n connection with the riliing of the counter-bore, I employ a novel species of fixed ammunition. I make use of a cartridge, B, the shell or case of which is so made or prepared that its exterior will correspond with the shape of the interior of the riiied counter-bore and snugly iit therein. The exterior of the cartridge-case therefore has the same twist as the grooves of the counter-bore. The interior form ofthe cartridge B also corresponds with its exterior. 'Ihe interior of Kthe cartridge case corresponds in form and size very closely to that of the riiied bore of the barrel. tridge-case thus made receives and holds one or more balls, either rounded or elongated, which have had their surfaces previously prepared to correspond with and exactly it into the rilied grooves of the bore of the gun. When a cartridge of this kind is inserted into the rilied counter-bore the exterior of the cartridge-case, following the twist of the rifled grooves, will carry and hold the ball or balls in exact line with the ried grooves of the bore; and when the powder is exploded the prepared balls will pass through the ried grooves of the bore with comparatively little resistance, having been accurately fitted to the grooves beforehand.
I prepare the balls by using a section of a ritied barrel as a die or mold, through which I force the metal by means of a suitable plunger. The exact fitting of the balls into the riiied grooves ofthe gun is thus secured. Ialso prepare the cartridge-shells by using a section of the counter-borel as a die with a plunger ofthe form and size of the rilied bore.
The exterior of the elongated balls may be covered with patches, as shown at K, before the balls are placed within the cartridge-shells. When the balls are to be thus covered the die by which they are to be prepared must be made The car-A smaller thanv the bore of the gun to allow for the thickness of the patch. When thus covered the possibility of leading the barrel is prevented and the friction ofthe ball in the barrel is much reduced and much greater accuracy is obtained in consequence of the fact that the surface of the patch is not worn off so fast as the surface of the ball would bc if the latter were in direct contact with the grooves ofthe""" bore. Abetterfitbetween the ball and the bore ofthe gun is thus maintained.
The shells of the cartridge may be composed of metal or fibrous substance, or both combined; or anyothersuitable material that can be pressed, cast, or made into the form described may be employed.
In comparison with the ordinary breechloading guns the use of my improvements presents manyimportantaud strlkin g advantages.
Guns made as I have described with a ritled counter-bore' will offer but little resistance to the passage of the balls through the rifled gun. The balls, having been hardened and accurately fitted to the riiied grooves beforehand, will undergo no compression or channeling. Hence their range, penetration, and accuracy with a given degree of recoil will far exceed that of' the ordinary breech-loading guns.
By the use of my improvements I am enabled to reduce the friction or resistance encountered bythe ball in passing -through the gun, and I am therefore enabled to use a larger charge of powder or a quicker burning quality of powder without increasing the force of the recoil. The more powder burned the more gas is produced and the greater is the velocityimparted to the ball when the ball leaves the muzzle ofthe groove. In the use of the ordinary breech-loading tire-arms the resistance of the ball, dueto its sudden compression into the ried grooves, is so great, owing to the nature of the surfaces in contact, that much less velocity is imparted to the balls during its passage through the barrel than is obtained by the use of my improvements. In my gun the ball is not checked by any resist` ance of compression, but starts with the commencement of ignition, or as soon as sufficient gas-pressure is generated to overcome the inertia of the ball, and the ball is driven with increasing velocity by the increasing volume of gas as ignition proceeds. My improvements thus enable me to-make use of a much heavier projectile in proportion to its diameter than is desirable to use in the ordinary breech-loading rifled guns, and thereby I obtain greater moment-um for my projectiles with less air-resistance than is practicable in the use of the ordinary breech-loading guns.
My invention greatly facilitates the employment of cartridges containing a series of balls which may be simultaneously discharged. Two kinds of ammunition may be used in connection with my gun-namely, single-ball cartridges, as shown in Fig. 6, for long-ran firing, or three-balled cartridges, as Asho Fig. 3, for short-range or volley firing.
l i l .L
All rilled breech-loading lire-arms at present in use, so far as I am ir1l'ormed,are limited to a single ball'. When it is attempted to use faces of all the balls are destroyed, and they are jammed together in the form of a plug, as before stated. But in my improvement, the balls having been all previously hardened, litted, and prepared for the rilied bore, when the cartridge is inserted the lands on the balls are placed inline with the grooves ot' the barrel, and when ignition of the powder takes place the balls pass from the gun with so little resistance that their contactlsurfaces of the ball and gun cannot be materially affected.
When the ordinary cylindrical or smooth counter-bore is employed itis obvious that the balls cannot receive previous preparation to Vlit the grooves ot' the gun. Itis required that the surfaces of the balls used with the smooth counter-bore shall be compressed into the rifled grooves of the barrel of the gun after the powder is ignited.
Another important advantage ot' my improvement is that by the simple act of introducing the cartridge into the counter-bore several balls may be simultaneously and accurately litted into position in line with the grooves of the gun, ready for rino. Thus the flight of the balls will be accurate, whether a single heavy ball for long-range firing be used, or two or more lighter balls for shortrange or volley tiring be employed.
Any degree of scattering or spread of the balls after leaving the gun may be allowed by varying the density ot' the metal composing the balls, and by alteringthe tightness of their lit within the bore of the gun.
By the use of my improvements the soldier, when in action, may vreadily change the character of his amunition to suit the constantlyvarying nature ot' his service-using the long or short range cartridges as circumstances require.
One of the great disadvantages of nearly all lire-arms now used, whether muzzle or breech loaders, is the difticlty of easily regulating the execution of the arm, so as to suit it for short or long range service. Cartridges carrying a single heavy bullet for the longest range ot' which the gun is'capable are now almost invariably employed in allbreech-loading riled fire-arms. By the use of my improvement these balls might be divided into three balls and all of them tired with sufticient power for any distance which it is desirable to shoot in volley-tiring, thus trebling the effect of the same weight of ammunition.
My improvements are intended for use in connection with various forms of breech-closing devices; and the cartridges here described may be discharged by a blow of the hammer upon any portion ot' the shell thereof, or by l means of a percussioncap, as will be readily understood by all gun-makers and persons skilled in the art.
I do not claim broadly the preparation of the projectiles to t the bore ot' the gun, nor the employment of such projectiles in guns that have a ritled bore of uniform size extended through the entire length of the barrel.
' I do not claim broadly the extension of the rifled grooves to the rear ot' the charge-chamber, whether in single barrels or in revolving cylinders of tire-arms.
Having thus described my invention, I claim as new and desire to secure by Letters Patent.
The ritling or grooving of the counter-bore ot' breech-loading tire-arms, substantially as and for the purposes herein shown and described.
HIRAM BERDAN.
Witnesses THEO. TUsoH, M. M. LIVINGSTON.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456011A (en) * 1945-07-17 1948-12-14 Musser Clarence Walton Apparatus for aligning preengraved projectiles in rifled firearms
US2699094A (en) * 1947-02-19 1955-01-11 Musser Clarence Walton Rifled firearm which automatically indexes preengraved projectiles
US3505924A (en) * 1967-04-18 1970-04-14 Allied Res Ass Inc Silent mortar
US3667390A (en) * 1969-10-29 1972-06-06 Forsvarets Fabriksverk Explosive weapons and fragmentary elements therefor
US3736693A (en) * 1967-03-08 1973-06-05 Heckler & Koch Gmbh Firearm barrel
US20040034385A1 (en) * 1997-11-07 2004-02-19 Paul Gilson Embolic protection device
US6739083B2 (en) 2001-09-12 2004-05-25 Bore Science Technologies, L.L.C. Runout correction rifle barrel
US20040236368A1 (en) * 2003-04-29 2004-11-25 Mcguckin James F. Distal protection device
US20140075805A1 (en) * 2011-07-11 2014-03-20 Mark C. LaRue Firearm barrel having cartridge chamber preparation facilitating effiecient cartridge case extraction and protection against premature bolt failure
US9702650B1 (en) * 2012-11-15 2017-07-11 The United States Of America As Represented By The Secretary Of The Army Weapon blast attenuation

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456011A (en) * 1945-07-17 1948-12-14 Musser Clarence Walton Apparatus for aligning preengraved projectiles in rifled firearms
US2699094A (en) * 1947-02-19 1955-01-11 Musser Clarence Walton Rifled firearm which automatically indexes preengraved projectiles
US3736693A (en) * 1967-03-08 1973-06-05 Heckler & Koch Gmbh Firearm barrel
US3505924A (en) * 1967-04-18 1970-04-14 Allied Res Ass Inc Silent mortar
US3667390A (en) * 1969-10-29 1972-06-06 Forsvarets Fabriksverk Explosive weapons and fragmentary elements therefor
US20040034385A1 (en) * 1997-11-07 2004-02-19 Paul Gilson Embolic protection device
US6739083B2 (en) 2001-09-12 2004-05-25 Bore Science Technologies, L.L.C. Runout correction rifle barrel
US20040236368A1 (en) * 2003-04-29 2004-11-25 Mcguckin James F. Distal protection device
US20140075805A1 (en) * 2011-07-11 2014-03-20 Mark C. LaRue Firearm barrel having cartridge chamber preparation facilitating effiecient cartridge case extraction and protection against premature bolt failure
US8938903B2 (en) * 2011-07-11 2015-01-27 Mark C. LaRue Firearm barrel having cartridge chamber preparation facilitating efficient cartridge case extraction and protection against premature bolt failure
US9702650B1 (en) * 2012-11-15 2017-07-11 The United States Of America As Represented By The Secretary Of The Army Weapon blast attenuation

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