DOCSLIB.ORG

Impulse and Momentum What Is Momentum? Mass in Motion

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Impulse and Momentum What Is Momentum? Mass in Motion Chapter 7 Impulse and Momentum What is momentum? Mass in Motion. p mv How hard something is to stop. hard to stop small mass, big velocity p = m v hard to stop, big mass, small velocity P = M v Hard to Stop! MV STOP IT! Dp = F Dt = = F Dt What is Impulse? Impulse changes momentum. Dv F ma m Dt FD t m D v Dmv I F D t D p Stop it! Hay stack or Concrete Wall? Dp = F Dt = = F Dt Same Impulse & Change in Momentum Different Force, Different Time Dp = F Dt = = F Dt Stop It! Same Impulse, different Force and Time. 7.1 The Impulse-Momentum Theorem There are many situations when the force on an object is not constant. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. 7.1 The Impulse-Momentum Theorem DEFINITION OF IMPULSE The impulse of a force is the product of the average force and the time interval during which the force acts: J FDt Impulse is a vector quantity and has the same direction as the average force. newton seconds (N s) Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. 7.1 The Impulse-Momentum Theorem J FDt Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. 7.1 The Impulse-Momentum Theorem DEFINITION OF LINEAR MOMENTUM The linear momentum of an object is the product of the object’s mass times its velocity: p mv Linear momentum is a vector quantity and has the same direction as the velocity. kilogrammeter/second (kg m/s) Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. 7.1 The Impulse-Momentum Theorem v v a f o Dt F ma mv mv F f o Dt FDt mvf mvo Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. What is the average Force exerted on a 0.140 kg baseball by a bat given that the ball’s initial velocity is 45.0m/s and its final velocity, after 1.3ms impact, is 65.0m/s in the opposite direction? pmv00 (.14 kg )( 45 ms / ) 6.3 kgms / pff mv (.14 kg )(65 ms / ) 9.1 kgms / Dpp f p0 9.1 kgms / ( 6.3 kgms / ) Dp 15.4 kg m / s I Dp (15.4kg m / s ) 4 F 1.18xN 10 Dt 1.3xs 103 + Bug Splat Compared to the FORCE that acts on the bug, how much force acts on the bus? More Same Less Newton’s 3rd Law: FFbus bug bug bus Bug Splat Compared to the IMPULSE on the bug, how much impulse is on the bus? More Same Less FFbus bug bug bus Fbus bugD t F bug bus D t Bug Splat Compared to the IMPULSE on the bug, how much impulse is on the bus? More Same Less FFbus bug bug bus Impulsebug -Impulse bus Bug Splat Compared to the Change in Momentum of the bug, the momentum of the bus changes? More Same Less Impulse Dp Impulsebug -Impulse bus Dp-bug Dpbus Bug Splat Which undergoes the greater acceleration? F Bug Same Bus a m Which suffers the greatest damage? Bug Same Bus Bounce/ No Bounce Bullets You are at a war protest when the cops start shooting pellets at the rowdy anarchists. Which would you rather be hit with, rubber bullets that bounce or don’t bounce? Both have the same mass & initial speed. Bounce: Dp m( vf ( v0 )) m( v0 v 0 ) 2 mv 0 No Bounce: Dp 0 mv00 mv Newton’s Third Law FFaction reaction Newton’s Third Law DDppFF ballaction cannon reaction DDtt Dppball D cannon ()()mb v bf m b v b00 m c v cf m c v c mb v bf m c v cf m b v b00 m c v c pp Conservation of total,, before total after Momentum! Conservation of Momentum If there are no external forces acting on a system of objects then the total momentum before an event is equal to the total momentum after an event. ppbefore after The system 100kg 100kg pbefore mv 0 mv THE EVENT v p 2 m mv after 2 Conservation Depends on The System 100kg 100kg pbefore mv THE EVENT External v Force! pm after 2 Momentum is NOT conserved! Colliding Systems For momentum to be conserved you must define The System so all the forces are internal to it and there are no net external forces. Include everything that gets hit. Conservation of Momentum If there are no external forces acting on a system of objects then the total momentum before an event is equal to the total momentum after an event. ppbefore after System: You define the system so that momentum is conserved. •No external forces acting on the system •Internal forces cancel out and don’t change momentum •Include all the objects that collide or ‘go bump’ •Always apply conservation laws to a system When you have defined the system so that the net external forces acting is zero, THEN & ONLY THEN can you invoke Conservation of momentum! ONLY AFTER you haveppbefore defined the aftersystem so that the net external forces acting on it is zero, THEN & ONLY THEN can you invoke Conservation of momentum and apply: Conservation of Momentum Momentum is conserved for which system? (a) (b) (c) INCLUDE EVERYTHING THAT GOES BUMP! NOTICE HOW THE INTERNAL FORCES CANCEL! The recoil momentum of a gun that kicks is more than less than the same as the momentum of the bullet it fires. Momentum is conserved for the system including: gun alone gun + man gun + man + bullet Frictionless surface Charlie and his gun, m = 80kg, shoots off a bullet, m =.01kg, straight ahead at 300 m/s. What is Charlie’s (+gun) recoil velocity? 1. Define the System so net external forces is zero. 2. THEN momentum is conserved ppinitial final pcharlie,,,, i p bullet i p charlie f p bullet f 0 ppcharlie,, f gun f ppcharlie,, f bullet f mc v cf m b v bf .01kg mb 300ms / Frictionless surface vvcf bf 80kg mc .04ms / Other Exploding Systems ppinitial final Rocket Thrust 0 Mvrocket mv gas Dprocket Mv ppinitial final Mvrocket mv gas Dpprocket D gas Dpgas mV Rocket Pushes Gas Out. Gas Pushes Back on Rocket. Collision Systems: Total Momentum is Conserved Once the System is properly defined Momentum is conserved for all Collisions. Total momentum before = Total momentum after. Elastic Collisions: Bounce Momentum is transferred! Total momentum before = Total momentum after Inelastic Collisions: Stick Total momentum before = Total momentum after Collision Decision Both trucks have the same speed and mass. After they collide they will: a) Bounce off each other b) Stick and move to the left c) Stick and move to the right d) Stick and stop dead in the center e) Vaporize Inelastic Collisions: Stick Was Momentum Conserved in this case? Depends on the System! Elastic Collisions: Bounce What is the System so momentum is conserved? If the mass is the same what is her final velocity? 1 2 ppinitial final mv1i mv 2 i mv 1 f mv 2 f v1i v 2 i v 1 f v 2 f 2m/s v2f v 1 i v 2 i v 1 f v2 f 2 m / s ( 1 m / s ) ( 1 m / s ) 1 2 v2 f 2/ m s Momentum is Exchanged! Elastic Collisions What if you didn’t know the final velocity of car 1? Could you still find the final velocities? 1 2 Use Conservation of Momentum AND Kinetic Energy! Solve 2 equations for two unknowns: the velocities! pp 1 2 f 0 KEf KE0 Elastic Collisions ppf 0 mv1ff mv 2 mv 10 mv 20 1 2 KEf KE0 12 1 2 1 2 1 2 mv1ff mv 2 mv 10 mv 20 2 2 2 2 Plus lots of Algebra!! Can you use this method to 1 2 solve for Inelastic Collisions? Kinetic Energy is NOT Conserved! Inelastic Collisions Granny (m=50kg) whizzes around the rink at 3m/s and snatches up Andy (m=25kg). What is their final velocity? (Ignore friction) Before After Granny: m=50kg, v =3m/s Inelastic Collisions 0 Andy: m=25kg, v0=0 What is the system? ppinitial final Before After Granny: m=50kg, v =3m/s Inelastic Collisions 0 Andy: m=25kg, v0=0 m1 v 1if() m 1 m 2 v ppinitial final mv11i v f ()mm12 50kg 3 m / s 1 (50kg 25 kg ) 2 2/ms Before After Collisions Momentum is conserved for all Collisions. Momentum is transferred during Collisions. Elastic: The total Kinetic Energy of the system is conserved. Think Bounce! Inelastic: The total Kinetic Energy of the system is not conserved. Think Stick! Why is momentum conserved during Inelastic Collisions but kinetic energy is not? Inelastic Collisions Kinetic Energy is ‘lost’ to heat & other kinds of energy. There is only one kind of momentum. Therefore it is conserved. 7.2 The Principle of Conservation of Linear Momentum Example 6 Ice Skaters Starting from rest, two skaters push off against each other on ice where friction is negligible. One is a 54-kg woman and one is a 88-kg man. The woman moves away with a speed of +2.5 m/s. Find the recoil velocity of the man. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. 7.2 The Principle of Conservation of Linear Momentum Pf Po m1v f 1 m2v f 2 0 m1v f 1 v f 2 m2 54 kg 2.5m s v 1.5m s f 2 88 kg Copyright © 2015 John Wiley & Sons, Inc.
Load more

Recommended publications
  • Experimental Measurement of Rifle Dynamics During the Range Shooting of Biathlon Weapons
    Available online at www.sciencedirect.com ScienceDirect Procedia Engineering 112 ( 2015 ) 349 – 354 7th Asia-Pacific Congress on Sports Technology, APCST 2015 Experimental measurement of rifle dynamics during the range shooting of biathlon weapons Andrey Koptyug*, Mats Ainegren SportsTech Research Center, Mid Sweden University, Akademigatan 1, SE-831 25, Östersund, Sweden Abstract Some of the shooting training that biathletes implements takes place indoors, even in hotel rooms or at home, through so-called "dry firing" training. It involves imitating shooting at a target with real rifle but without ammunition, when the result is evaluated by various electronic devices counting the number of virtual hits. But dry firing cannot adequately represent real shooting, as it does not produce any rifle recoil, which significantly limits its value for the training. To reach a higher realism of the dry firing training a system mimicking the weapon recoil is therefore needed. Present research aims to overcome an existing lack of data on the dynamics of small caliber rifles recoil dynamics. Present paper describes first measurement results acquired in the controlled environment of the shooting range. Two types of experiments were carried out with firing freely suspended rifle and when backed with the force measurement device (load cell). Average recoil peak force values were reaching 5 kg, rising from zero for about 10-15 ms and keeping altogether for about 30-40 ms. Corresponding energy going into the recoil motion of the rifle is found to be about 390 J. The measured values provide an adequate input for designing the devices mimicking the biathlon weapon recoil in dry firing training.
    [Show full text]
  • Engineering Design Handbook Guns Series Muzzle Devices.Pdf
    UNCLASSIFIED AD NUMBER AD838748 LIMITATION CHANGES TO: Approved for public release; distribution is unlimited. FROM: Distribution authorized to U.S. Gov't. agencies and their contractors; Administrative/Operational Use; MAY 1968. Other requests shall be referred to Army Materiel Command, Alexandria, VA. AUTHORITY USAMC ltr 22 Jul 1971 THIS PAGE IS UNCLASSIFIED AM Lp - AMC PAMPHLET ENGINEERING DESIGN HANDBOOK GUNS SERIES MUZZLE DEVICES 3 0 SF' lC£8 ' m® -WY SUM * ©?V BOT DKTHTIJ HEADQUARTERS, U.S. ARMY MATERIEL COMMAND MAY 1968 REDSTONE SCIENTIFIC INFORMATION CENTER nun 5 0510 00231346 5 FTEADQUARTERS UNITED STATES ARMY MATERIEL COMMAND WASHINGTON, D.C. 20315 AMC PAMPHLET 17 May 1968 No. 706-251 ENGINEERING DESIGN HANDBOOK GUNS SERIES MUZZLE DEVICES This pamphlet is published for the information and guidance of all concerned. (AMCRD-R) FOR THE COMMANDER: OFFICIAL : CLARENCE J. LANG Major General, USA Chief of Staff Chief. Administrative Office DISTRIBUTION Special AMCP 706-251 PREFACE The Engineering Design Handbook Series of the Army Materiel Command is a coordinated series of handbooks containing basic in- formation and fundamental data useful in the design and develop- ment of Army materiel and systems. The handbooks are authorita- tive reference books of practical information and quantitative facts helpful in the design and development of Army materiel so that it will meet the tactical and the technical needs of the Armed Forces. This handbook is one cf a series on Guns and presents informa- tion on the fundamental operating principles and design of muzzle devices. Because of higher priorities assigned in the past to other activities, progress in the design of bore evacuators, noise suppres- sors, and smoke suppressors was not shared with that of muzzle brakes, blast deflectors, and flash suppressors.
    [Show full text]
  • 1) a Moving Electron of Mass Me and Initial Speed V1 Collides Head on with an Initially Stationary Hydrogen Atom of Mass Mp
    1) A moving electron of mass me and initial speed v1 collides head on with an initially stationary Hydrogen atom of mass mp. The collision is elastic and remains 1-dimensional. If mp / me = 1840: (a) What is the center of mass velocity? (b) What does this collision look like from the center of mass reference frame? Draw two pictures (before and after ). (c) what fraction of the electron’s initial kinetic energy is transferred to the Hydrogen atom ? 2) A certain spring is found not to conform to Hooke’s law. The return force it exerts on being 3 extended a distance x is found to be F = -(k1x + k2x ). a) Compute the potential energy function for this force. b) If a mass m is attached to the spring and stretched out to a distance xo, what speed will it have on release when it is at the position x = xo/2 ? 3) A stone of weight w is thrown vertically upward into the air from ground level with initial speed v0. If air drag exerts a force of constant magnitude f on the stone throughout its flight: a) what is the maximum height reached by the stone ? b) what is the return speed just before impact on the way down ? 4) A 1400 kg cannon fires a 70 kg shell with a muzzle speed of 556m/s.If the cannon is mounted on frictionless rails and set at an elevation of 39 degrees above the horizontal: a) What is the recoil speed of the cannon? b) At what angle with respect to the ground is the shell projected? 5) Newton's second law is best stated in terms of momentum because in that form variable mass problems can be simply treated.
    [Show full text]
  • Simulation of Cannon Recoil Dynamics for Light Vehicles Using Single Body Models
    UNCLASSIFIED/UNLIMITED Simulation of Cannon Recoil Dynamics for Light Vehicles Using Single Body Models David C. Rutledge, Ph.D. Staff Engineer United Defense 4800 East River Road Minneapolis, MN 55421-1498 [email protected] SIMULATION OF CANNON RECOIL DYNAMICS FOR LIGHT VEHICLES USING SINGLE BODY MODELS Firing a large caliber cannon mounted on a lightweight vehicle can result in severe pitching reaction angles and driver accelerations. These dynamic responses must be small enough to allow the crew and vehicle to fight effectively, hence their prediction is a key aspect of weapon integration with land vehicles. United Defense uses two classes of models to predict cannon firing dynamics: • Single body, time invariant, models that focus more on delivering timely results. These are best used to close in on the correct answer, which is appropriate for rapid prototyping efforts and trend studies. • Multibody transient dynamic models such as Dynamic Analysis and Design System (DADS), which can deliver more accurate results. Such models are used for detailed design and development. The single body, time invariant, vehicle/suspension models developed at United Defense contain simplified representations of vehicle components, resulting in reduced modeling fidelity. The primary simulation inputs include firing impulse and peak force. The vehicle mass properties, geometry, and position of any stabilizers then determine vehicle response. The primary outputs are vehicle reaction angle and driver acceleration, which are determined by calculating the initial angular velocity, pitching and rolling moments, and lateral force from firing. The outputs are typically plotted as a function of cannon azimuth and elevation. The models are then tuned to correlate with previous results from firing data and DADS simulations, increasing their accuracy.
    [Show full text]
  • The Artillery News
    THE ARTILLERY NEWS. JUNE – AUGUST 2007 Official Correspondence. R.A.A Assoc. of Tas. Inc. Hon. Secretary, Norman B. Andrews OAM., SBStJ. Tara Room, 24 Robin St; Newstead. Tas. 7250. E-Mail: [email protected] R.A.A. Association of Tasmania Inc. Homepage: http://www.tasartillery.o-f.com/ R.A.A.A.T. NORTHERN HISTORICAL- SOCIAL WING. APRIL 2007 The second informal get-together for 2007 of the R.A.A.A.T. Historical- Social Wing group was held at the QVM&AG at 2.00 p.m. on Thursday 12th April, 2007 and was attended by:- Norman Andrews (Hon. Sec.), Gunter Breier, Terry Higgins, Graeme Petterwood, Lloyd Saunders, Marc Smith, Frank Stokes, Charles Tee and Rick Wood.. We did receive apologies from several members - and we were aware of others who are still on the sick list – so ‘Get Wells’ are extended We also extend our sincere sympathy to our member Bob Brown who recently lost his dear wife through illness. Hang in there Bob…! Norm read several notes he had received from other Associations regarding their activities and also advised us of an invitation from Reg Watson regarding the Annual Boer War Commemorative Day which is to be held on Sunday 10 June 2007 commencing 12.00 noon at the Boer War Memorial in Launceston’s City Park. There will be an opportunity to present flowers, posy or wreath in memory of those Tasmanians who fought in and perhaps died in the South African War (1899-1902) Further inquiries phone Reg Watson 0409 975 587. 1 Launceston contact also will be Mr.
    [Show full text]
  • Recoil Reduction Method of Gun with Side to Rear Jet Controlled by Piston Motion
    S S symmetry Article Recoil Reduction Method of Gun with Side to Rear Jet Controlled by Piston Motion Ming Qiu 1,*, Peng Si 1, Jie Song 1 and Zhenqiang Liao 1,2 1 School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; [email protected] (P.S.); [email protected] (J.S.); [email protected] (Z.L.) 2 School of Mechanical and Electrical Engineering, Global Institute of Software Technology, Suzhou 215163, China * Correspondence: [email protected] Abstract: Excessive recoil severely restricts the loading of high-power traditional guns on modern vehicles. To reduce the recoil without breaking the continuous firing mode and reducing the projectile velocity, a recoil reduction method that controls the lateral ejecting of propellant gas by a piston was proposed. The recoil reduction device is symmetric about the barrel axis. First, a one-dimensional two-phase flow model of interior ballistic during the gun firing cycle was established. Next, the MacCormack scheme was used to simulate, and the piston motion was gained. Then the propagation of the rarefaction wave in the barrel was presented. Finally, the propulsion difference between the piston-controlled gun and the traditional gun was discussed. The results showed that the recoil momentum was reduced by 31.80%, and the muzzle velocity was decreased by just 1.30% under the reasonable matching of structural parameters. Keywords: two-phase flow; recoil reduction; rarefaction wave; piston motion; fluid-solid coupling Citation: Qiu, M.; Si, P.; Song, J.; Liao, Z. Recoil Reduction Method of Gun with Side to Rear Jet Controlled 1.
    [Show full text]
  • Rifle and Shotgun Recoil Test System
    Rifle and Shotgun Recoil Test System A Senior Project presented to the Faculty of the Department of Mechanical Engineering California Polytechnic State University, San Luis Obispo In Partial Fulfillment of the Requirements for the Degree Bachelor of Science in Mechanical Engineering by Benjamin Canfield-Hershkowitz Trevor Foster William Meijer December 2013 © 2013 Benjamin Canfield-Hershkowitz, Trevor Foster, and William Meijer Statement of Disclaimer Since this project is a result of a class assignment, it has been graded and accepted as fulfillment of the course requirements. Acceptance does not imply technical accuracy or reliability. Any use of information in this report is done at the risk of the user. These risks may include catastrophic failure of the device or infringement of patent or copyright laws. California Polytechnic State University at San Luis Obispo and its staff cannot be held liable for any use or misuse of the project. ii Abstract This project for Weatherby, Inc. requires a simple device to test the recoil force of their shotguns and rifles to determine the effectiveness of recoil suppression methods. A bench mounted device that secures the gun and records firing data to a portable computer was created. This project was completed for the Senior Project requirement for a Bachelors of Science in Mechanical Engineering from California Polytechnic State University, San Luis Obispo. The completed prototype was successful in measuring the recoil force and energy for Weatherby’s rifles. The recoil energy from the prototype differed from the calculated theoretical recoil energy with a small enough percent error to be deemed accurate. The differences between these values are lower than the margin of error for all measurements.
    [Show full text]
  • Gunsmithing Price List
    Gunsmithing Price List General Labor Rates Inspect and Prepare quote Free Boresight Scope $15.00 Mount and Boresight Scope $25.00 Minimum Shop charge $40.00 Labor by Hour $80.00 General Services Complete Cleaning (DCOA disassemble, clean, oil, assemble) $60.00 Rust Removal / Excessively Dirty +$20.00 Zero Rifle at range (not including ammunition or rage fees) $60.00 Trigger Work starts at $80.00 Stock Services Inlet & Glass Bed semi inlet stock $80.hr Install Aluminum pillars and glass bed $120.00 Glass Bed Finished Stock $100.00 Install Swivel Studs $50.00 Inlet stock for new bolt handle $60.00 Fit & Install Recoil Pad (not including price of pad) $45.00 Muzzle Brakes Remove & Reinstall New Brake or Silencer $40.00 *If very hard to remove, i.e. red Loctite +$20.00 1.16.18 Wood Refinishing by Style Hand rubbed oil finish High gloss leaving grain of wood open $200.00 Hand rubbed oil finish High gloss completely filling the grain $320.00 Sprayed on oil, Satin finish open grain $140.00 Sprayed on oil, Satin finish filled grain $220.00 Sprayed on oil, High Gloss filled grain $300.00 Each of the following is an additional charge of $40.00 and will be assessed at the standard labor charge Oil soaked stocks Removal of Large dents Crack repair Stripping epoxy Staining 1.16.18 --------------------------------------------------------------------------------------------------------------------- Metal Finishing Black Oxide and Parkerizing: (Includes disassembly, abrasive blasting and reassembly) Pistols: $120.00 Rifles/Shotguns: $175.00 Removing scratches and pitting: $80/hour Bluing: (Includes disassembly, abrasive blasting and reassembly) Pistols (Matte Finish): $150.00 (Semi): $180.00 (High Polish): $200.00 Rifles/Shotguns (Matte Finish): $200.00 (Semi): $250.00 (High Polish): $300.00 *Matte Finish is minimal scratch/pitting removal and abrasive blasting before the bluing process.
    [Show full text]
  • Higgs Recoil Mass and Cross-Section Analysis at ILC and Calibration of the CALICE Siw ECAL Prototype H
    Higgs Recoil Mass and Cross-Section Analysis at ILC AND Calibration of the CALICE SiW ECAL Prototype H. Li To cite this version: H. Li. Higgs Recoil Mass and Cross-Section Analysis at ILC AND Calibration of the CALICE SiW ECAL Prototype. High Energy Physics - Experiment [hep-ex]. Université Paris Sud - Paris XI, 2009. English. tel-00430432 HAL Id: tel-00430432 https://tel.archives-ouvertes.fr/tel-00430432 Submitted on 6 Nov 2009 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Universit´ede Paris-Sud LAL 09-118 Centre d’Orsay Octobre 2009 Higgs Recoil Mass and Cross-Section Analysis at ILC AND Calibration of the CALICE SiW ECAL Prototype par Hengne LI M. A. Djouadi Rapporteur Mme J. List M. R. P¨oschl Directeur de la th`ese M. M.A. Thomson Rapporteur M. G. Wormser Pr´esident M. D. Zerwas To my wife Xiaoying and my daughter Emma. Abstract The major topic of this dissertation is the study of the Higgs recoil mass and the cross section measurements using the Higgs-strahlung process with Z µ+µ− and → e+e−, based on the detailed ILD detector simulation.
    [Show full text]
  • 25 Pounder Quick Firing Gun Development During World War I the Main British Field Guns Were the 18 Pounder QF Gun and 4.5 Inch Howitzer
    25 Pounder Quick Firing Gun Development During World War I the main British field guns were the 18 pounder QF gun and 4.5 inch howitzer. The 18 pounder fired a fixed round at 1615 feet per second which meant the range of the gun could only be varied by changing the elevation at which the barrel was fired. Its elevation was restricted to between -50 and +160 for the Mark II or +360 for the Mark IV (range 6525 and 9300 yards respectively). The 4.5 inch ammunition was separate loading, it being possible to separate the shell and cartridge. The brass cartridge case contained five charges. Range of the howitzer could be varied by both changes in elevation and changes to the number of charges used in the cartridge. It fired a 35lb shell to a maximum range of 6600 yards (later 7300 yards) with an elevation of between -50 and +450. 18 Pounder shrapnel round The 4.5 inch cartridge case 4.5 inch round showing the showing the brass cartridge showing the five charge bag projectile seated in the brass case which is fixed to the rings. Removal of rings cartridge case. The projectile projectile. commenced from the top and is not fixed to the case would result in a lower muzzle allowing the removal of velocity and therefore charge bags from the case. decrease in range. Soon after the end of World War I the Royal Artillery Committee, in conjunction with the Director, Royal Artillery began examining various options for a new field gun with a planned range of 15,000 yards and the combined capabilities of both the gun and a howitzer.
    [Show full text]
  • Stress Analysis of Integrated 12.7 Mm Machine Gun Mount
    Scientific Technical Review, 2016,Vol.66,No.4,pp.47-51 47 UDK: 623.56.622.4.547.551.2 COSATI: 19-06, 20-11 Stress Analysis of Integrated 12.7 mm Machine Gun Mount Aleksandar Kari 1) Dušan Jovanović1) Damir Jerković1) Nebojša Hristov1) The paper describes the problem of integration 12.7 millimeters machine gun on the mobile platform. Based on the dimensions of the machine gun modeling of machine guns mount with cradle is done. The completed model is fully functional and realistic. Using optimized internal ballistic parameters the calculations of recoil forces and loading of mount and rotating bearing are executed. The loading calculation of bearing was made in two ways. In the first case finite element method is applied and software package FEMAP was used. The second method is based on calculating the resistance components of bearing from the equilibrium condition. At the end the comparative analysis of data obtained from these two methods was done. Key words: machine gun, caliber 12.7 mm, recoil force, stand, bearings, load calculations, stress analysis, finite element analysis, integrated weapon. Introduction Table 1. Tactical - technical characteristics of machine gun M87 HE resistance of weapon and its firing stability depends Characteristic Value T on the value of recoil forces [1]. In the case of the Caliber, d 12,7 x 108 mm integration of weapons, if the barrel is rigidly connected to the Barrel length, l 1100 mm mount, the recoil force is fully transmitted to the mount. In Total length of machine guns, L 1560 mm order to avoid inconveniences of such connections, or Weight of machine guns, m 24,8 kg extended firing time load mount and to reduce its intensity, Rate of fire, n 700 bullet/min.
    [Show full text]
  • Why Demand Realistic Recoil?
    WHY DEMAND REALISTIC RECOIL? it only looks this easy Until you pull the trigger... Pull the trigger on any firearm and you will immediately understand Newton’s law about equal and opposite reactions. Recoil is an inseparable part of shooting. It instantly affects how you engage the target. And the effects are amplified for machine guns. Each machine gun round changes the lay of fire. Recoil makes the barrel on a .50 caliber dance as the weapon fires. Add on the long effective range of the weapon and that barrel dance means rounds can fan wildly as they streak down range. Gunners must constantly adjust to the recoil and re-engage the target. Fact is, training with recoil is critical. Why is realistic recoil missing from so many Machine gun trainers? Most machine gun simulators don’t even have recoil. It’s simple: put sights on the target and shoot happily certain that you’ll stay on target all the time. GUN ACTIVE RECOIL But, it’s utterly unrealistic...just a simple video game. ACME’S Gun Active Recoil Unit (GAR®) is a Some machine gun simulators provide ‘notional’ patented, electro-mechanical system that recoil. These guns may buzz a bit or lightly pop-pop- replicates the recoil intensity of the actual pop using compressed gas. And gas systems just don’t provide high rates of fire or realistic recoil. weapon when firing. It’s full-force recoil at full rate of fire for machine guns. The idea is that notional recoil reinforces the cue ® when the gunner fires. But, notional recoil doesn’t The GAR system does not require blanks or really disrupt the weapon sight picture or drive pneumatic charges – it simply plugs into an ® the weapon off target when firing.
    [Show full text]