US2432539A - Grenade launching tube and auxiliary cartridge therefor - Google Patents

Description

PkESSu/IE IN TUBE 26 Dec. 16, 1947. c. R: oLsEN 2,432,539

GRENADE LAUNCHING TUBE AND AUXILIARY CARTRIDGE THEREFOR Filed April 19, 1944 EharlES Rnlneri Elsen Patented Dec. 16, 1947 GRENADE LAUNCHING TUBE AND AUXIL- IARY CARTRIDGE THEREFOR Charles Robert Olsen, Philadelphia, Pa.

Application April 19,1944, Serial No. 531,840

2 Claims. (Cl. 42-1) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) i The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

fThe invention relates to means for launching grenades and other projectiles from rifles, carbines, projectors, and the like, and has for an object to provide means for increasing the practicable range of these projectiles without risk of injury to the rines or their mechanism, and without increased risk to-personnel beyond that to be expected in use of projecting devices generally for such purposes.

It is a special purpose of the invention to provide an auxiliary propellent charge which will become effective immediately succeeding and continuing the `initial pressure peak in the barrel resulting from the firing ofthe conventional grenadelaunching ammunition round or the like.

The latter has been designed to produce a peak a'pressure peak far beyond a safe limit for the :proper use of the rifle. Vguiding motive in the invention to preserve the It has therefore been a benet of the use of a reasonably fast burning .powder in the grenade launcher cartridge, so

that a peak pressure will be developed promptly during the initial movement of the grenade and toimplementthis by an Vimmediately following Vignition of an explosive which will add to the gasesalready acting against the grenade, in sufcient quantity to continueor produce a renewed and relatively flat pressure peak well before the grenade leaves the launcher.

. Afurtheraim is to present a novel means for -obtaining the augmentation of propulsion in such devices.

An important desideratum in the invention is lthe formation of a novel auxiliary cartridge for producing the elects and functions desired.

A very important object in view is to enable the use ofk standard matriel (including rines and carbines, launchers, and grenades) already in hand and use, for launching grenades, signals, rockets and other projectiles, without change, except to the extent of the simple addition of an auxiliary cartridge which may be a unitary ele- 'ment of the grenade, or may be manually placed in loading.

,Y 'further important object of the invention is to provide an improvement as indicated above Where a prior Carbine, grenade-launching cartridge, launcher, and grenade are employed, a velocity of 145 feet per second just beyond the muzzle has been the optimum, but my invention has produced velocities of 220 feet per second without exceeding the safe pressure limits of the arm. The range attained with the mentioned prior matriel, approximates 202 yards, more or less, when the carbine is given an elevation of degrees; while with my invention a range of 390 yards has been shown, using the same carbine, grenade launching cartridge, launcher, and grenade, and at the same elevation but with my auxiliary cartridge device included, as will be described. The invention is thus particularly important for use with the Carbine, making this light weight weapon of service in a much wider scope, and particularly in grenade launching, where it has heretofore been of restricted value. Improvement in range with the rifles such as the Garand, Springeld and Enfield are also similarly manifest, and in the launching of rockets similar advantages are obtained. In the rifles,

while the standard grenade launching cartridges for riiies produce higher velocities than the carbine ammunition, I am still able to use my auxiliary without change, using the same quantity of propellant component, with higher velocities and increased range, although not in the same relative proportion as with the Carbine. The increased ranges with the rifle equal those with the carbines, however, and are all that are at present required for the improved utility of grenade firing. While a special riile auxiliary cartridge with a larger charge similarly proportionate to the riile grenade launching cartridge content may be made, it is not considered necessary or desirable in View of the ranges actually obtained with the single device, which simplifies manufacturing and supply procedure, and also avoids possibilities of mistake or confusion, such as might involve use of a heavy charge rifle auxiliary cartridge in the carbine launcher.

It is a specic aim of the invention to evolve a novel means for effecting ignition of an auxiliary propellant charge element, as well as to enable the ready incorporation thereof in a conventional grenade and grenade launcher in a simple way.

Additional objects, advantages, and features of invention reside in the construction, arrangement and combination of parts involved in the embodiment of the invention, and in the method of practice thereof, as will be more clearly apparent from the following description and accompanying drawings wherein:

Fig. l is a perspective View of the muzzle of a rifle on which a conventional grenade launcher is shown., withmy auxiliary cartridge and aigrenade tailpiecein position for loading.

Fig. 2 is a full size longitudinal section of the launcher with my auxiliary cartridge and grenade loaded. 1 A

Fig. 3 is a cro-ss section on the Vline A3---3 ofFFig. 2. Fig. 4 is an enlarged longitudinal section of the auxiliary cartridge.

Fig. 5 is a similar View showing a I:preferred form of the auxiliary cartridge.

Fig. 6 is a representation of a fictitious se't `oif curves representing at A, maximum .strength of barrel; B, safety pressure allowance; C, con'ventional ball cartrldge pressure curve; D, 'pressures produced by the small charge carbine size regular ygrenade laune-her cartridge and G, pressure increment of my auxiliary 'as well as lat a Ageneral indication of the resultant of 'the itwfo last named pressures during launching o'f a grenade.

Fig. 7 vis a fictitious graph similar to Fig. 6 showing 'what is believed to be substantially the pressures in -t-he grenade launcher tube during the firing operation.

Fig. 8 yis a view of a tridge,

Reference is also made to the patents to W.

Moore, No. 2,335,299, and J. C. fG-arand, No.

1,892,141, for details of the arm, attachmentfand conventional practice with cartridges-of propellant for -use in launching grenades.

Referring more particularly -to the drawings, 'there is illustrated vone well 'known-form of grenade launcher lil attachable to landA detachable from a riiie 'il or 'the like; the i-llustration-show primary propellant caring only the muzzle end l2 of the rifle barrel, the

forward 'extremity 13 of the stock, and part foi the gas cylinder 'lfd fof a well known automatic or semi-automatic rifle. The launcher l0 is of Aa well known construction with means lltor secure Yit vd'eta'chably to the barrel with lthe tubularbody o r piston element 'l5 `of the launcher alined and in gas receiving relation `with the borey ofthe barrel. As is well known the launcher io-r the automatic rifle Valso includes lni-'ea-ns ito cause venting of gases from the attached riil'e otherwise than through the end 'of the'barrel. None oi these particular features of "known structure other -than the body of the 'piston are illustrated or described in detail hereincomprising no vnovel part of. my invention, Construction of the grenade or other projectile tio be llaunch'e'djalso may remain 'unchanged as heretofore constructed, and details other than the tail-piece l5 'andimmediately connected 'part of a 'grenade body I7 are not illustrated. The tubular launcher piston |15 shown full size in Fig. 2, hasA the usual closely spaced nar-row land rings I8 .at the forward end, more widely spaced narrow intermediate lan'd rings i8, and rearmostwide lands 2li., 'Theinteri-or also is the usual .smooth-bored cylindrical chamber 2l m-uchlarger in diameter than, the bore of the rifle on which the launcher is applied, andope-ning rflush through the forward end of the piston ordinarily but in this instance shownas flared or interiorly'beyelled as at 2-2at the mouth of the muzzle, aiordingA a Vconical seat.

The grenade i i may conform to approved 'practice for trifle grenades .or'inay be varied 'to'accorjd with improved practice, as may be. .found desirvable. It has an interiorly threaded nipple Zitat its rear extremity coaxial with the center `of gravity -of the grenade, and into this there is screwed a corresponding tenon2i1sof the head 25 of a tail piece tube 26,*this tube being smoothly slidaldie upon 'the body for pisten 145 of the launcher, and extending nearly to "the -rearmost wide land 20, the next forward wide land being -within the tube and supporting the same in convcentric relation .to Vthe launcher body. The tube 4hasat its 'rear end the usual tail ns 21.

rFor use with the launcher and grenade with Ktail ip'iece as .above described, I have formed an auxiliary cartridge 28, somewhat resembling an ordinary shot 'gun shell, and loaded with an aux- This cartridge in the present instance comprises a case 29 of cylindrical form, adapted tot "slidingly in the forward end rci" the bore '2| c'f the launcher piston tube I5. It may fit loosely in the launcher so as to most certainly assure .its free withdrawal with 4the igienade at .the 'proper time. In the presentinstance "the case 29 is 4'formed with fa head f3() .having fa peripheral flange 3| with =a cornical outer -face iai-ranged to .lit the vbevel'led seat 22 or mouth of the tubular -1; iston,andthe head 25 :iscom'pleteLv .received in the bevelled seat fclear from `the exA- -tremity of the :body 25. This lauxiliary Acartridge 'case may be formed of 'any low cost water proof -expen'dible material, Jincluding ipaper, plastics, 'and metal.; and 'in use, ithus far, has .been made `of brass .to `expedite production. The case may be of such length as required vto accommodate therewithin the 'auxiliary charge fof yenplosiile determined lfon. For rifles this may fbe variedi-n -quan'tity between-twenty to thirty fgrains or :more of a powder produced Aby the 'I. fdu Pont de Nemours Companygof WilmingtouDe-laware, and

lknown asEXliQ'-6, olf'r 'somewhat viincrgrfain but 'oi values. simi-lar to those fof the standard .powder used in :the Vgrenade firing cartridge, -now standard for use-in rines. yThis latter standard cartridge ordinarily employs about forty grains of smokelessror pro powder, plus about ve ygrains of black powder.

.For the icarbineithis known grenade firing l'can tridge may be vVaried somewhat, Abut the -chamge in my auxiliary 'cartridge-fused in the U. Si. carbine, `caliber 30,.ML has consisted of from twenty to thirty grains fdf the powder EX48`09-'6 with satisaCt'OryfreSuitS', 'the larger amount giving. a. range fof. 390 .yards with the 'Carbine :set with its butt against :a :stationary :support and fel'evatedlito-'an Aangleo'f Iforty-live degrees, which isth'e standard angle for :nringgrena'deswfromsuch weapons.

'Thefena'r-ge :is retainedinrthe Nbymeam's 'or l'a Wad -33 has heretofore be'e'n ymade 'of thin fast-burning "cardboard, covered with a standard red: lacquerA 32. In one form the wad .hasbeen imperorate, 'as fat J3 in '4, butipre- V`e'r'ably., for maximum range with; a girone-barge,

and to attain greater uniformity fof. performance, thewad isv formed as at 34 in Fig. 5, with one 'ormore vrelatively large perforations 35 covered with a lamentary sheet or septum 36 ofl Waterproof quickfburning material. This has :been madey of tissue-gpaper coated with shellacf, and may also consistl of. such paper coated or saturatedwith -a cellulose compound or an .N-H power solution.. The `single hole 35 shown has been made approximately two ii'fthsfthe diameterof the .interior of the ease. While I .have heretofore used as the initial propellant a standard cartridge with a Vusual .pyro' powder, 'this V'may be'mod'iiedi desired, bythe use of' a double base .powder `to attain a quicker peak pressure, and

earlierfa'ction of the products 'ofi-'ts combustion and( to assure prompt ignition of the auxiliary charge. "The burrring'andY volumetric values and characteristics of the auxiliary charge may also be modified with a View to obtaining pressure curve values and resultant composite curve corresponding tothe eiects represented as an objective of the invention in Fig. 7.

In the practice of my invention, manufacturing and shipping practices as heretofore followed are carried out, with those additional involved in producing the auxiliary cartridge. No special shipping cases, handling, or space will be required.

Thus, as is known, grenades are shipped in kits with a grenade-firing cartridge for a particular weapon packed in the tail tube of each grenade, and there is ample room for my auxiliary cartridge also in each tail tube. Other shipping practices are also possible,

In firing, usual practices may be followed as heretofore, in setting the gun and loading after applying the launcher, and the grenade may also be launched by firing the gun from the shoulder. The latter practice requires a knack of leaning to the gun for satisfactory results and may be carried out by men of moderate weight, as has been demonstrated. Owing to the coordinated timing of the explosion of my auxiliary charge, the force of the kick of the gun is not increased beyond that experienced when using the usual grenade-launching cartridge, but the recoil is longer sustained requiring the shoulder -to be held firmly against the butt of the stock but yielding without the marksman becoming unbalanced rearward.

My auxiliary cartridge with a charge of twenty grains has been fired from the shoulder with good results.

The gun with launcher being ready, the auxiliary charge is set in place as shown and described, after which the tail tube of the grenade is slipped over the body of the launcher. A single grenade firing cartridge 38 is then introduced into the chamber of the gun accompanied by usual cocking of the weapon. The gun being properly emplaced or pointed, the trigger is operated to fire the first cartridge. The gases thus evolved move rapidly through the gun barrel and chamber of the piston with only moderate or relatively gradual rise of pressure, substantially as at D in Fig. 6, until opposed by the inertia of the grenade, when there will be a prompt rise to the peak of the pressure curve approximately as at E. Movement of the grenade and cooling will then quickly tend to cause a drop in the pressure curve. In the meantime, however, the covering of the auxiliary charge will have been burned, and the auxiliary charge ignited, producing an explosion acting in a direction counter to the preceding movement of the products of combustion of the rst charge accompanied by high momentum in the newly evolved gases as well as added pressure, and, due to the relief of pressure which is then progressively occurring in the products of the irst charge by cooling and expansive chamber action, the tendency of the second charge to build a maximum peak of its pressure while confined by` the grenade on a curve such as at E, is first cushioned and somewhat relieved in the tube by a momentary further compression of the gases in the chamber 2| and gun barrel. It may be noted that the nature of the wad 33 is Such that it offers no material impedance to the discharge of gases from the shell 29 when red and a high if not maximum expansion-pressure value is immediately derived from the second propellant charge when fired, substantially as described above. With the foregoing and the accompaniment of the falling pressure curve of the first gases a more gradual rise of the pressure accretion is effected, approximately as at G, with a resultant aggregated eifect approximated by the curve H. The fall of the latter curve will then parallel the curves of the first and second charges, maintaining a comparatively high pressure even in its descending part. This descending part of the curve of aggregate pressures will coincide with the final movement of the tail sleeve from the piston or body of the launcher. In consequence of the eiects noted, the pressure curves in the tube 26 will vary from those in the chamber of the firearm.

The case 29 is carried away with the grenade in the operation described although no material rocket effect is manifest in the performance of the grenade. The case falls near the gun.

The body of air in the rifle or Carbine barrel and in the launcher chamber 2| is a material factor in delaying and determining the coordination of the explosion of the auxiliary cartridge, and the septum materials 33 and 36 serve as ignition propagating means as well as protective and slight delay means.

I claim:

l. In combination, a grenade-launching tube constructed and arranged to be carried by its rear end, on the muzzle end of a rearm barrel, an auxiliary cartridge held in the forward end of said tube, the end of said cartridge facing the rear of the tube being adapted for ignition by propellant gases in the tube and the other end of said cartridge being closed, and a grenade having a tube portion slidably tted on the launching tube, said auxiliary cartridge being rearward of and a separate entity from the grenade whereby the said cartridge may be applied separately from and prior to mounting of the grenade.

2. In the combination of claim 1, an annular shoulder on the forward end of said launching tube and a complementary annular portion on the cartridge whereby the motion of the cartridge into the tube is limited.

CHARLES ROBERT OLSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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