Rotary Chamber Mechanisms

The preceding chapters of this publication are concerned with the operating and design principles of automatic weapons which employ a reciprocating bolt and derive the energy required for full automatic operation from blowback, long recoil, short recoil, or gas sources. There is another class of weapon, known as the revolver cannon, which is sufficiently different from the weapons described up to this point to merit individual and carcful consideration. The principal difference between the...

Jimt r

Note that in the last two terms of equation 2-12, no consideration is given to the overtravel which was allowed in the design. (See fig. 2-3.) The resulting error is so slight that there is no need to complicate the equation further by taking it into account. Since T' is the total time required for one complete cyclc of operation, the rate of fire in rounds per minute will be If it is assumed that the losses arc negligible, the times required for the barrel and bolt to return to the firing...

Feed Systems

Belt holding pawl omitted from this area for clarity shoulder in feedway supports cartridge rim while grippers snap over the rim view of mating cams surfaces on the operating rod and belt feed slide spring loaded lever forces incoming round into line with the chamber Cam Grooves on Operating Rod Actuate Belt Feed Slide

The Machine Gun

The kinetic energy corresponding to this velocity is These values show that with the assumed conditions of pressure, gas port location, orifice size, piston area, and piston mass, the piston velocity and piston energy obtained are relatively high values. It can also be seen that changing any of these factors can have a marked effect on the values of enerev and velocity. For example, these values could be increased tremendously by moving the gas port closer to the chambcr, increasing the piston...

Kkr

The expression for the time to recoil when the spring constant is zero can not be obtained from equation 1-11 because substituting K 0 yields an indeterminate expression. However, the expression can be derived by substituting K 0 in equation 1-8 and solving the resulting differential equation. This gives the relation between recoil distance and lime as (1-17) T ' iv > VD d For the conditions of equation 1-16, K 2 F v D, where FttV is the average spring force over the distance D. For the...

D

The effect of the bolt driving spring on the bolt velocity can be estimated as follows The initial compression of the spring at the instant of piston impact is equal to F0'2 Foa f DK2 25 + .0207 X10 X 12 25 2.48 27.5 (lb.) The force exerted by the spring at a 10-inch deflection is Therefore, the average force of the spring (taken with respect to time) over the 0.018 second required for completion of the bolt travel may be estimated roughlv as (This estimate is not exact because the velocity of...

Baldwin

Report of firing tests of Baldwin 37 mm automatic semi-flexible aircraft cannon. Dayton, O., 1919. (Cannon test no. 10) Illustrated. LT. S. Bureau of Aircraft Production Report of flight test of 37 mm Baldwin gun mounted in Glenn L. Martin gunnery ship. Dayton, O., 1919. (Cannon test no. 3) Object to determine effect on the ship of firing gun in air. Results almost negligible. Illustrations. Report on test of 3 7 mm Baldwin gun mount in the Glenn L. Martin gunnery ship. Dayton, 1919. (Cannon...

Preface

Held to the strictest interpretation of the definition1 and to the means by which the function is accomplisheds there is only one primary force that actuates any automatic weapon namely, the energy generated by Ihe explosion of (he powder charge contained in the chamber of the barrel. There have been, to date, only two known means that can be derived from (his source of power that have resulted in successful operation (1) the rearward thrust of the recoiling maaa and (2) pressure generated in...

Info

Linkless Continued Tage 5-59 Jap Model 11 (1922) 6.5 mm gun 282-283 5-60 U. S. Pateni 290,622 J. G. Aedes 22 Apr 1890 284 5-61 U. S. Patent 1,447,860 J. S. Johnston 6 Mar 1923 284 5-62 First column Breda Italian MG 131 (German) MK 108 (German) 285 Second column MG 42 (German) U. S. 20 mm Soviet Soviet U. S. 20 mm 285 5-63 German 50 mm ammunition 286 5-64 Kricghofl MK 303 (German) 286 5-65 Mauser MG 81 (German) 286 5-66 Jap 20 mm 5-67 Model 11 6.5 mm machine gun (Jap) 288 5-68 Jap...

40mm Gun Magazine Feed Drawing

Advanced Primer Ignition

Blowback Gases Atomize Small Quantity of Oil Lubricating Chamber. Oil Is Pumped blow back gases suck oil into the cham8er Figure 5-70. Blowback Gases Atomize Small Quantity of Oil Lubricating Chamber. Oil Is Pumped quantity of oil necessary to lubricate the chamber oil for the next shot runs into cylinder in front of the piston

Bolt Velocity

Velocities in a Blow back Gun. Figure 1-8. Velocities in a Blow back Gun. ante of the driving spring can be ignored completely. NOTE There is one point which requires spccial clarification at this time. In many descriptions of blowback actions, it is strongly implied that the driving spring contributes a substantial portion of the resistance which limits the acceleration imparted to the bolt by the powder gases. Actually, this is not so. Although it is true that the driving spring...

Moq

A line representing this value of the maximum velocity of free recoil is drawn on the velocity graph (fig. 3-21) and the curve previously drawn from equation 3-16 and fig. 3-8 is extrapolated until it becomes tangent to the line. The point at which the curve becomes tangent represents the time at which the residual pressure becomes zero and therefore imparts no further velocity to the recoiling parts. Although an error in locating the exact point of tangency will not have any serious effect on...

Blowback And Blowforward

To provide new repeating fire-arm, which is loaded automatically and throws firing pin back to its place by back action of the charge and also discharges cartridge-shell automatically. Consists of cylinder sliding in breech-block, of a firing pin sliding in cylinder and in a bushing on breech-block, and of a device for automatically loading and discharging cartridge shell. Patent 581,296 Mannlicher, Ferdinand von Relates to firearm in which barrel resting...

Recoil Operation

Shortly after unlocking occurs, the barrel (which is still moving to the rear of its own momentum) strikes the accelerating device (fig. 2-14C). This device can take many forms, but in the mechanism illustrated, it is a lever pivoted in the breech casing. Fig. 2-15 shows the action of this lever in detail. In fig. 2-15A, the barrel extension is just in engagement with the lever and in fig. 2-15ft the lever has been rotated to where it has started to thrust on the bolt. As the barrel continues...

Skoda

Skoda machine guns. (Manuscript) Notebook with details, pictures of weapons. La mitrailleuse Skoda, mod. 1902, et son emploi. Pilsen, 1902. 41 p. Illustrated brochure on products of firm. (In French) Outlines history, development and principal products of firm. Illustrated. Skoda Works, Pilsen, Czechoslovakia. 1945. 90 p. (CIOS Target Nos. 2 27h, 18 93, 19 19, and 21 45) Discussion of conventional artillery and ammunition made there, steel treatment, methods of manufacture. Brief description of...

Uji Machine

Energies Affecting Motion of Bolt During Action of Accelerating Lever. .006 .007 .008 .009 TIME (SEC.) Figure 2-26. Energies Affecting Motion of Bolt During Action of Accelerating Lever. Fig. 2-26 shows the curve obtained by using this relationship to determine the decrease in the kinetic energy of the barrel. This curve does not represent the energy transferred to the bolt because the remaining blowback action and the incidental losses still must be considered. The effects of the...

Bredamachine Gun Magazines For Sale

First report on Italian gun, medium machine (A. F. W.) 8 mm (0.3150 inch) Model 38, Breda and 16th report on Ordnance program no. 5826. 16 Apr 1943. Air cooled, gas operated, magazine feed with quick change barrel. Nothing outstanding or new about the gun. Illustrated. 7.7 mm mg und 12.7 mm mg (Ital.) Breda Safat Berlin, 1944. Description, operation and maintenance. Illustrated. (In German) Breda anti-aircraft and anti-tank machine gun caliber 20 mm. 1934. Description, functioning, mounting,...

Plain Blowback System

The problems encountered in controlling the bolt velocity in a blowback gun can be appreciated best by analyzing the so-called plain blowback system. In this system, blowback provides all of the operating energy and the motion of the cartridge case is limited only by the inertia of the bolt. NOTK As will be explained, the plain blow-hack system is not suitable for application in a high-powered heavy machine, gun. It is treated here because it serves to illustrate many of the basic principles...

Lahti

Finland 20 mm gas operated machine sun for airplanes. 20 Sep 1936. Additional information on L-37 Finnish machine gun with photos. 20 mm gas operated machine gun for airplanes. 16 Jun 1936. Describes L-37 machine gun used in Finnish Air Force and designed by Finnish government rifle factory. Valtion Kivaaritehdas State Rifle Factory The L S machine rifle, model 26 32. Jyvaskyla, Finland, 1933. Unique feature permits firing of cartridges of different calibers. Brochure describes and illustrates...

Mcclean Pistol 1903

Handbook of the McClean one-pounder automatic gun, Mark III, with instructions for its care. n. d. Parts list and illustrations included with handbook. Motor balloon guns automobile vs. airship. In Scientific American, Jan 15, 1910, p. 48 Discusses mounting of machine guns on motor vehicles, including McClean-Lissak automatic gun mounted on Packard truck. Illustrated. Naval Proving Ground, Indian Head, Md. Proof tests of 37 min gun, Russian type, manufactured by Poole Engineering and Machine...

Krieghoff

Notes on materiel Gun, machine, light, cal. 7.92 mm T-44. Dec 1944. Conversion of German FG-42 Krieghoff paratrooper gun, with MG 42 belt feeding mechanism. U. S. Naval Powder Factory, Indian Head, Md. Gun, machine, cannon, aircraft, 20 mm experimental 1938 I German. 1 May 1946. Brief description of incomplete captured German Krieghoff cannon. Photo. L . S. Naval Powder Factory, Indian Head, Md. Gun, machine, cannon, aircraft, 20 mm experimental 1941 ---German. 27 Mar 1946. Preliminary report...

Knorr Bremse

Description of a new fully-automatic fire-arm Model LH33, according to Swedish patent application no. 4908 1933. 1933. Description, parts list and photos. Also describes 20 mm heavy machine gun, M LH, corresponding in construction with LH33. Description of a new light machine gun of system L. H. 33 according to English patent 430641. 1936. With illustrations, parts list. L. H. 33 machine gun. Mar 1941. Sectional drawings. Light machine gun LMG 35 36. 15 Dec 1936. Report no. 15,021 Describes...

Annotated Bibliography

Appendix B is a rccord of the principal sources on automatic weapons. These sources include books, magazine articles, pamphlets, manuals, and official reports and documents. Each entry includes author or issuing agcncy, title, date, series number, and other identifying data, followed by a brief description of the contents and special features of the work. For security reasons, many references on recent and proposed weapons under development in the United States and other countries can not be...

Bolt Return Spring

Bolt Fortner

Method of Retaining an External Captive Recoil Spring. operating spring mounts on outside of receiver Figure 19-2. Method of Retaining an External Captive Recoil Spring. cross pin retains operating spring in operating rod Figure 19-3. Captive Spring Used To Return Breech Bolt and Operating Rod. Figure 19-3. Captive Spring Used To Return Breech Bolt and Operating Rod.

Fiat

Equipment, general, Fiat machine gun. 9 Jun 1928. Report L. 11064 Summarizes data on SAFAT light machine gun, Fiat light mg Model 1928 Fiat 12 mm anti-aircraft ing, and Fiat aircraft mg model 1928 A. Italian developments in field of machine guns. 12 Jan 1927. Contains translation of description of Fiat Machine Gun, Model 1926 cal. 6.5 mm and description of Fiat 25 mm a a machine gun designed by Revelli. Photos of Model 1926 gun.

Casing

Simplified Schematic of Blowback Mechanism With Ad vanced Primer Ignition. is arranged to ignite the primer of the fresh cartridge just before the bolt reaches its fully forward position. Although the details of an actual gun of this ivpc may be considerably different in form from the schematic representation shown in fig. 1 -20, the basic mcchanism shown illustrates the essential mechanical function. The fundamental parts of the mechanism are the bolt which backs up the cartridge ease and is...

Brno Zb- 50 Machine

Test of gun, light machine, BRNO-ZB cal. 7.92 nun. Czech. 28 Jul 1945. Description and photo. BLG M. G. ZB 60. Brno, Czech., n. d. Translation of manual for this weapon 15 mm Advantages and tactical use arc outlined. Gives types of ammunition used. Light machine gun model ZB-26. Brno. 1934. Translation of manual describing 7.92 mm ZB 26. Drawings and photographs. Translation of manual with description, action, assembly, magazine, special equipment, and principal advantages. Photos of plant,...

U S A E F

Report on Dreyse machine gun, giving description and action. 27 Feb 1919. Contains translation of German pamphlet 'Lcitfadcn fur das Dreyse M. G.'' giving nomenclature, action, description of weapon and its parts. The light machine gun 1 3 Dreyse 30 Oct 1935. Report no. 14,356 Operation shown by means of series of photos. Diagrams show tactical use. Summary report on Bcrgmann machine gun, mod. 1915 n. A. and Dreyse machine gun. 1 Apr 1919. Summary report no. 197 Characteristics and description...

Beardmore Farquhar

The Bcardmorc-Farquhar light machine gun. 1919. Contains description and operating procedure. Attached is a British repoit Grain Armament Report no. 123, Oct I, 1919 on firing trials of the gun at high altitudes. Compared favorably with Lewis gun in every respect. Test of Beard more-Farquhar light machine gun. 15 Aug 1919 Report of British test of gun which docs not greatly impress the observer. Beardmore-Farquhar machine gun. 16 Aug 1919. Report no. P gt 020 Includes clipping from The Times,...

Lewis

The romance of invention VIII The one-man machine gun and its inventor. In Scientific American, Feb 14, 1920, p. 160 Describes Col. I. N. Lewis and the success of his gun in WW I. Illustrated. Ordnance and the world war. N. Y., 1920. Describes trials of Lewis gun by U. S. Army Gen. Crozier was Chief of Ordnance dept. First tests unsuccessful, but later acceptable and adopted. Defense of government against accusations of Lewis supporters. Detail drawings and descriptions of the Maxim and Lewis...

Revelli

Data on the Cannoncino autoinatico Fiat 25.4 mm. 24 Jun 1918. 14 p. Also known as 25.4 semi-automatic Revelli, model 1917 cannon chambered for 1-inch ammunition. Contains drawing showing ScarfT mounting for use in airplanes. Gives component parts and operation of cannon. Revelli automatic machine gun. Villar Perosa, Italy, 1917. Illustrated manual of weapon manufactured by Officine di Villar Perosa in Italy and Canadian General Electric Co., Toronto. Revelli automatic rifle. 11 Sep 1929. Report...

Extractor

Advantage of Using Special Cartridge Base Form for Blowback. point shown in fig. 1 6A as is necessary to allow for the presence of the extractor in the extractor groove . If a cartridge case with the spccial base form shown in fig. 1-6B is used, the cartridge may be pushed further into the chamber and when it is blown back it may therefore travel a greater distance before the walls near the base become unsupported. By this means, the allowable bolt velocity during the first. 0.01...

The Mchine

Effect oi Bolt Driving Spring on Motion of Bolt After Reversal of Motion at Backplate. the bolt motion curves in fig. 2-30 up to the time that the bolt strikes the accelerating lever. 10. Motion of barrel before accelerator is reengaged In order to give the barrel return spring a chance to start the barrel moving before the bolt reaches the accelerator lever, the barrel should be unlatched while the bolt is still some distance from the point at which the accelerator will be...

Machinegun Feedway

Feedway Machine Gun

Oiler Valve Actuated by Movement of Cartridges Through Feedway. perforated cartridge wiper oils incoming round Figure 5-67. Oiler Valve Actuated by Movement of Cartridges Through Feedway. spring-loaded oiltank pump-type valve spring loaded valve actuated by incoming round Figure 5-68. Oiler Valve Actuated by Movement of Cartridges Through Feedway, Wetting the Wiper Brushes. Figure 5-68. Oiler Valve Actuated by Movement of Cartridges Through Feedway, Wetting the Wiper Brushes....

Maxim

Detail drawings and descriptions of the Maxim and Lewis rapid fire machine guns. In Scientific American, Feb 6, 1915, p. 130-37 Our enemies in the air. In Scientific American, Feb 9, 1918, p. 133 Shows Parabellum gun mounted in reconnaissance plane. The German anti-tank machine gun 13 mm 25 Aug 1921. Service Report Discussion of secrecy surrounding this gun T. u. F. put into service in German army in spring of 1920. Contains data on ammunition. Handbook of the 0.45-inch Maxim gun G. G. chamber...

Retarded Blowback System

One of the principal disadvantages of the plain blowback system is the excessive bolt weight required to limit the movement of the cartridge case to a safe value during the action of the powder gas pressure. This particular difficulty can be circumvented by employing the retarded blowback system a system in which a special type of retarding mechanism is operated by the movement of the bolt. The mechanism itself Is composed of relatively light parts and the inertia forces which result when these...

U S

Contains inclosurcs 1 Report of present information available in England with respect to aircraft cannon 2 Memorandum of conference regarding the status of the different types of 37 mm cannons in France at the present time, Puteaux Arsenal. The test and evaluation manual for aircraft guns. Dahl-gren, Va., Aug 1947 Manual provides single, uniform method of testing and evaluating aircraft gun-type weapons to provide the best possible index to the effectiveness and characteristics of these weapons...

Bofors

Brochure giving history and products of this armament plant. Photos and plates of plant and weapons. 25 mm automatic gun L 64. Bofors, Sweden, 1939. Characteristics and data on a a gun. Photos. 40 mm automatic naval gun L 60. n. d. Brochure giving characteristics and data on 40 mm Bofors, with drawings of weapon. 20 mm automatic aeroplane gun, L 70. 1953. NA Stockholm Report 72-53 Pamphlet inclosed with NA Report. Completely mechanical loading system. Normal...

Furrer

G. 25 Bern, 1942. 36 p. Manual on Swiss LMG 25 Furrer 7.45 mm. In German L S. Military Attache, Berlin Data for Ordnance Dept. 22 Mar 1933. M. I. D. 2296-367 8 Inelosures Data for light machine gun model 1925 Swiss Furrer with photographs. Intermediate caliber automatic cannon. 23 Feb 1939. Report no. S-2 Reports on new Swiss 20 mm Furrer cannon under development for aircraft. IJ. S. Military Attache, London Furrer machine gun. 15 Feb 1928. Report no. 21202...

Mauser

German 20 mm aircraft machine gun, Mauser MG 151 FMAR-169 I and several types of Mauser 20 mm ammunition A.P.I. FMAM-542 H.E.I. FMAM-354 H.E.T. FMAM-420 H E. FMAM-355 H E. FMAM-391 I. i FMAM 43 i . 21 Mar 1944. RC 2188 Contains firing data. Combined Intelligence Objectives Subcommittee Visit to Mauser Werke A. G. Oberndorf am Neckar, and Mauser personnel at Lager Haiming, Otztal, near Innsbruck. 1945. Interrogations of key personnel of Mauser firm at Obern-dorf and other places, including group...

Gas Operation

Since the gun and bolt are locked, the parts will assume some common velocity which is determined by the fact that the momentum of the combined mass after impact will be the same as the total momentum before impact. That is In the construction of the curves showing the motions up to the time of unlocking fig. 3-27 it was shown that the gun is fired during counter-recoil when it is still 0.0207 foot from its most forward position. As shown in fig. 3-34, the gun is 0.0805 foot from...

Rheinmetall

Test of German 30 mm aircraft cannon MK 108A3 and companion ammunition FMAR 462 FMAM-HET 996, FMAM-HE 997 and FMAM-HEI 998 1944. OR amp DC 4693 Description and results of tests. Tables and photos. 29th partial report on test of machine guns and machine gun accessories and first partial report on the test of the Solothurn 2 cm machine gun model S5-106. 28 Oct 1933. Ordnance Program no. 50821 Object of tests to check the functioning of the mechanism and to check the ballistic characteristics of...

Browning

Data on Japanese aircraft machine guns, 12.7 mm fixed mount Browning type 31 Jul 1943 O. P. no. 5826 Description and pertinent data on gun from Japanese bomber. Photos of weapon and components. The caliber .50 machine gun its conception. In Army Ordnance, Mar-Apr 1945, p. 271 Personal story of examination of Hotchkiss J o-inch gun being tested secretly by French in 1917, which led to its being sent to U. S. for tests which resulted in request for similar weapon with higher velocity the Browning...

Puteaux

Note sur les canons autoinatiques de 37 mm. Sep 1922. In French some pages translated into English Description and functioning of cannon mounted in Hispano-Suiza motor. Illustrations include detailed diagrams of guns. Special new French 37 full automatic guns. 8 Feb 1923. Description of 2 new guns developed at Puteaux Arsenal, one to fire through propeller, the other free. 37 mm Putcaux automatic airplane motor gun. 22 Dec 1925. General description and history of Putcaux gun, including canceled...

Kip

Substituting this value in the equation for t gives to evaluate C When t 0, d 0 and therefore Substituting this expression for C gives the equation for the time, t, required to recoil any distance, d. Solving this equation for d gives the inverse relation expressing the distance recoiled in any time, t. d K Sin LVsir sm KD FJ K Kqnation 1-9 may also be used to obtain the total time T required for the bolt to move through the entire recoil distance D. Substituting D for d gives T V il' Sill_1 1...

Nordenfelt

Handbook of the 0.45-inch 5-barrel Nordenfelt guns, Marks 1 and II. London, 1894. Drawings. Handbook of the 1 4-barrcl Nordenfelt gun. London, 1889. Contains illustrations and diagrams. Mitrailleuse automatique mod le 1897 de la Soci t Nordenfelt de Paris In Revue d'artillerie, Vol. 52, 1898, In French. Description and illustration of weapon. Letter to Capt. Chadwick, USN, 24 May 1884. Lists suggestions for naval armament of machine guns, other than those of rifle caliber, by using same system...

American Armament

Y., Dcc 1936 Brochure on Type M movable and Type F fixed 37 mm aircraft guns. Specifications, description and illustrations of guns are included. Description and photographs of gun, with operating instructions. Artillery for the air In The Aeroplane, Mar 29, 1939, p. 402 Describes American Armament Corporation 37 mm cannon, being peddled in England. Illustrated. Tactical aspect of flexible airplane cannon. In 17. S. Air Services, Jan 1941, p. 15 Gives...

Pkr Machine

7-6 Operating Cycle of Gas-Actuated Single-Barrel Rotary Cannon. Bore Sealed by Obturating 7-7 Method of Firing Multi-Projectile Loaded Round 420 7-8 Operating Cycle of Multi-Barrel Motorized Rotary Cannon 421 7-9 Mechanism for Revolving Rotary-Type Feed 422 423 7-10 Method of Revolving a Rotary Cannon 7-11 Method of Scaling Bore on a Rotary 8-1 Recoil-Loaded Spring Accelerates Bolt to Rear 425 8-2 Pivoted Lever Accelerates Bolt to 8 3 Twin Levers Accelerate Bolt to 8 4 Gas Pressure on Muzzle...

Machine Gun Darne

Darne machine guns for aircraft, infantry, cavalry, tanks, anti-aircraft service, etc. St. Etienne, France, n. d. Brochure on various models of Darne machine guns. Photographs of weapons. Historique de la creation de la mitrailleuse svsteme Darne. St. Etienne, n. d. In French Contains photos of weapons. Provisional manual for the use of the new Darne airplane machine guns, model for turret or wing of airplane and model synchronized for fire through the propeller. St. Etienne, France, 1925. 1925...

Principles Of Rotary

The preceding analysis deals primarily with the general operating and design characteristics which are inherent in any full automatic multiple-cham-ber weapon in which the chambers are separate from the barrel. In the analysis, consideration was given to those basic features which are significant regardless of what particular type of mechanism is employed. However, there is one type of multiple-chamber mechanism which has had a very prominent placc in modern gun developments. This mechanism,...

Degtyarev

Military Attache, Helsinki, Finland Degtyarev 7.62 mm LMG model 38. 26 Feb 1941. Report no. 289 Brief description of gun and its action. U. S. Military Attache, Riga, Latvia Degtyarev light machine gun. 23 Dec 1933. Report no. 8579 Based on official manual of Estonian general staff. General data, description, operation, etc. of 7.62 mm light Russian gun. Contains pictures. U. S. Military Attache, Riga, Latvia Organizational equipment Degtyarev light machine gun. 23 Dec 1933. Contains...

M adsen

Copenhagen, 1950. Brochure with photos, description and data on cal. .300 British model 1950 Madsen machine gun. The Madsen standard machine gun, model 1950. Trials at Mosede near Copenhagen on the 6th and 7th of Nov 1950. Copenhagen. 1950. Results of tests before representatives of Great Britain, Dominion of Canada, India, and U. S. A. of cal. .30 7.62 mm Madsen model 1950. 36,720 rounds fired with one weapon. 27 different tests. La mitrailleuse Madsen pour...

Ultrashkas Machine

Russian machine gun, 20 mm Shkas aircraft machine gun. 1 Oct 1941. Report no. 14,281 Description and data on subject gun. Russian machine gun, 7.62 mm Shkas. Description and particulars. 29 Sep 1941. Report no. 14,240 Description and photo of weapon. Russian small arms aircraft machine guns 15 Mar 1945. ETP TI Report no. 91 A Includes brief description and photos of 7.61 mm Shkas. U. S. GBI Enemy Equipment Intelligence Service Russian 7.62 mm aircraft machine gun. 18 Oct 1944 CBI Ordnance...

Uotchkiss

In Technical World magazine. Sep 1913, p. 714 15 Describes tests on Bcn t-Merci mounted in Faniian plane. Hotchkiss revolving cannon, Washington, 1086. Ordnance memorandum no. 27 Contains drawing of mechanism and ammo. Instruction pour les unites de mitrailleuses d'infanterie. Paris, 1932 Drawings and description of Ilotchkiss M 1914. In French Handbook of the .303-inch Hotchkiss machine gun provisional . London, 1917. Illustrated. Handbook of provisional...

Acknowledgments

With each volume of this series the debt owed to the many persons and institutions that have contributed to the project grows in size. I he following persons are listed in at least partial gratitude lor I heir help and encouragement Rear Adm. F. S. Withington, Chief of Bureau of Ordnance Rear Adm. M. F. Schoeftcl, former Chief of Bureau of Ordnance Rear Adm. P. D. Stroop, Deputy Chief oi Bureau of Ordnance. Capt E. B. Hooper. USN, Asst. Chief of Bureau for Research and Division Director Capt....

Blowback System With Advanced Primer Ignition

In the plain blowback system, the bolt returns to the Firing position with relatively low velocity but with considerable kinetic energy and this energy is absorbed by impact before the next cycle starts. Since the bolt is stationary when the new round is fired, all of the explosive force of the round is effective in accelerating the bolt to the rear. As has been explained, this condition requires the use of an extremely heavy bolt in order to keep the bolt velocity within safe limits. A...

Antoine Gazda And Oerlikon

March 1944. Memorandum reports 1-4 Results of firing of first 389 rounds are given. Interlock assembly failed to function after 125 rounds. Other malfunctions occurred. Second test 5-9 March 1944. Malfunctions again occurred. Third test 10-13 March 1944. Hammer broke during test. Gun withdrawn by inventor. Ballistic results of tests are given. Airpower only through firepower. From Minuteman, Sep 21, 1943 Wants hombers equipped with 20- and 23-mrn cannon as protection...

Lowell

Naval Experimental Battery, Annapolis, Md. Report of board assembled to examine and test Lowell battery gun, model oF 1879. Feb 24, 1879. Description of gun and test, with appended firing record. Illustrated. U. S. Naval Experimental Battery, Annapolis, Md. Report of board assembled to witness the trial of Lowell battery gun. Oct 3, 1876. Contains tabulation of firing and drawings. We think its mechanism brought to a nearer state of perfection than in any other machine gun with which we...

Kwd

Figure 17. Bolt Velocity Versus Time in a Plain Blowback Gun. a few feet per second. Furthermore, from the shape of the curve in fig. 1-7, it can be seen that even the maximum bolt velocity attained will not be much greater than this value. The second important point is that with such a low bolt velocity allowable, a high-powered plain blowback machine gun could never attain a reasonable rate of fire. To illustrate this point, the bolt of a 20-mm gun must open...

Oerlikon

Functional test of Japanese caseless gun, automatic. 40 mm, HO-301. 1947. Gun given preliminary examination then 56 rounds were fired, during which rate of fire, instrumental velocity, target dispersion, fuze function, and amount of breech and muzzle flash were observed. Aircraft gun which resembles Oerlikon a a 20 mm guns. Photographs. For free shell-guns. In Flight, Apr. 14, 1938, p. 309 An Oerlikon aircraft mounting with electrical drive. FFS model Illustrated. Handbook of the gun, machine,...

Hispano Suiza

86th partial report on functioning and mechanical test of machine guns and machine gun accessories and 1st partial report on test of Hispano-Suiza 20 mm automatic cannon, type 404, Birkigt patents. 1938. Illustrated. Tested Jun 21 to Aug 5, 1938. 20-mm automatic guns and materiel Record of Army Ordnance research and development. Dec 1945. Record of adoption, modification and development of Hispano-Suiza by U. S. since 1940, and its components. 122 illustrations from official sources, including...

Delayed Blowback System

All of the major difficulties associated with the design of blowback machine guns stem from excessive movement of the cartridge case during the time of action of the powder gas pressure. The preceding paragraphs show how the use of advanced primer ignition causes the initial high-pressure phase of the propeliant explosion to be expended in stopping the forward motion of the bolt, with the resulting advantages of a lighter bolt and a slightly higher rate of fire than would be permissible with...