US008925463B1

(12) Patent (10) Patent N0.: US 8,925,463 B1 Sullivan et al. (45) Date of Patent: Jan. 6, 2015

(54) PRESSURE RELIEF SYSTEM FOR GUN (56) References Cited FIRED CARTRIDGES U.S. PATENT DOCUMENTS (75) Inventors: Kevin Michael Sullivan, Kennebunk, 3,927,791 A 12/1975 Hershberger ME (Us); Marcelo Edgardo Martlllel, 4,892,038 A * 1/1990 Lubbers ...... 102/439 Cordoba (AR); Nicolas Horacio Bruno, 5,044,154 A * 9/1991 English _et al...... 60/223 Cordoba (AR); Brian Desmarais, 5,155,295 A 10/1992 camPOh Kennebunk ME (Us) 5,311,820 A 5/1994 Ellingsen ’ (Continued) (73) Assignee: KMS Consulting, LLC, Kennebunk, ME (Us) FOREIGN PATENT DOCUMENTS

. . . . . WO 2011071576 Al 6/2011 ( * ) Notice.. Subject to any disclaimer, the term of th1s OTHER PUBLICATIONS patent is extended or adjusted under 35 U.S.C. 154(b) by 167 days. Kohnken, KH. Ceramic Gun Barrels, Advanced Materials & Pro cesses; Sep. 2002, pp. 01-02. (21) Appl. No.: 13/597,640 _ (Cont1nued) (22) Filed? Aug- 29: 2012 Primary Examiner * Bret Hayes Assistant Examiner * Derrick Morgan _ _ (74) Attorney, Agent, or Firm * Karl F. Milde, Jr.; Eckert Related U-s- APPllcatlon Data Seamans Cherin & Mellott, LLC (63) Continuation-in-part of application No. 12/875,402, (57) ABSTRACT ?led on sep' 3’ 2010’ HOW Pat NO' 8,573,121 A high velocity munition comprises a projectile, mounted on (60) Provisional application No. 61/653,600, ?led on May a ca§e’ that can be ?red from an woman? cannon or 31s 2012, provisional application No_ 61/239,464’ vveapon. During storage or transport an IM venting deV1ce ?led on Sep 3 2009 1ncluded 1n the cartndge case prevents the propellant charge from ?ring the projectile, leaving the cartridge damaged, but ( 51 ) Int CL intact u P on P remature i gn ition. The lM vent exhaust channel F41A 17/16 (200601) is ?lled With a solid fusible material that melts at a lower F4 23 15/36 (200601) temperature than the ignition temperatures of the igniter (or (52) us CL primer) and the propellant charge of the projectile. At least USPC ...... 102/439; 102/430; 102/469; 102/481 one non-fusile rqureable member is included in the 1M (58) Field of Classi?cation Search vent channel and positioned to provide structural integrity to CPC F42B 33/04, F42B 39/00, F4213 39/1 4, the fusible material in the channel.Altematively or in addition """" u ’ ’ F42B 39/26 to the fusible material, a shape memory alloy ring surrounds USPC 102/430 439 4 69 470 481 202 1 the igniter (or primer) and separates from the cartridge When """""" u ’ ’ ’ ’ {02/ the cartridge reaches a temperature that causes auto-ignition. See application ?le for complete search history. 10 Claims, 14 Drawing Sheets

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(56) References Cited 2004/0107860 A1* 6/2004 Loubser ...... 102/481 2005/0115443 A1* 6/2005 Rastegar et al. 102/400 US PATENT DOCUMENTS 2005/0199055 A1* 9/2005 Browne ...... 73/17012 2007/0151473 A1* 7/2007 Brunn ...... 102/444 5,398,498 A * 3/1995 MOI-t et al‘ ““““““““““ H 60/223 2008/0006170 A1 1/2008 Haeselich 5,621,183 A * 4/1997 Bailey ““ n 102/202‘7 2010/0089272 A1* 4/2010 COOk et a1...... 102/481 5,735,114 A >1< 4/1998 Ellingsen “““““““““““ n 60/391 2010/0126887 A1* 5/2010 Kaddour et al. 206/216 5,936,189 A 8/1999 Lubbers 2011/0192312 A1* 8/2011 Toreheim et al. 102/469 6,321,656 131* 11/2001 Johnson “““““““““““ n 102/377 2012/0298005 A1* 11/2012 Kotefski et al. . 102/481 6 679 177 B1 >1< 1/2004 Wu et al‘ n ' 102/377 2013/0320010 A1* 12/2013 Kotefski et al. . 220/89.1 637523085 132* 6/2004 Roach n , 102/481 2014/0061515 A1* 3/2014 Traxleretal...... 251/11 7,051,511 B2* 5/2006 PrytZ ...... 60/223 7,107,909 B2 9/2006 Haeselich OTHER PUBLICATIONS 7’472’653 Bl * 1/2009 Hays et al' """"""""" " 102/481 “IM Solutions for Projectiles Crimped to Cartridges for Artillery $823351 """"""""" " ApplicationiPhase II, Transition from Cartridge Case Venting to 8’408’136 131* 40013 Lee ' """"""" " 102/377 Insensitive Propellant” by Carl J. Campagnuolo, Christine M. 835503004 B1 * 10/2013 W00 et al‘ ““““““““““ H 102/430 MiChieIlZi, Edward G. Tersine, Christine D. KHOH, William J. 8,584,588 B2 * 11/2013 Larousse et al, ,,,,,,,,,,,, ,, 102/481 AndrewsiNDIA IM/EM Symposium, May 11-14, 2009. 8,616,131 B2 * 12/2013 Kaddour et al. . 102/481 2003/0205161 A1* 11/2003 Roach ...... 102/481 * cited by examiner US. Patent Jan. 6, 2015 Sheet 1 0f 14 US 8,925,463 B1

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- US. Patent Jan. 6, 2015 Sheet 14 0f 14 US 8,925,463 B1 US 8,925,463 B1 1 2 PRESSURE RELIEF SYSTEM FOR GUN applied to a variety of munitions, be they ordnance, rockets or FIRED CANNON CARTRIDGES . These solutions include concepts of melting plugs alone or in combination with burst disks, memory alloy fas CROSS-REFERENCE TO RELATED teners or rings, as well as detonating cords and active venting APPLICATIONS devices using shaped charges, etc. Many applications of the concepts described have been developed on munitions rang This application is a continuation-in-part of the US. patent ing from grenade cartridge cases, rocket motor cases and application Ser. No. 12/875,402, ?led Sep. 3, 2010, and artillery projectile bodies, to fuses and warheads. However, entitled “Pressure Relief System For Gun Fired Cannon Car few such concepts have been applied to gun-?red munitions tridges.” This application also claims priority from US. Pro and even fewer relate to technology that disables ammunition visional Application Ser. No. 61/239,464, ?led Sep. 3, 2009, propulsion systems in response to IM stimuli. entitled “Pressure Relief System For Gun Fired Cannon Car 1.1 Prior Art: tridges;” the aforementioned US. patent application Ser. No. The prior art in this ?eld of Insensitive Munitions includes 12/875,402, ?led Sep. 3, 2010, entitled “Pressure Relief Sys a number of articles and patents that are relevant to the present tem For Gun Fired Cannon Cartridges” and US. Provisional invention. Typical of such prior art is the US. Pat. No. 5,936, Application Ser. No. 61/653,600, ?led May 31, 2012, entitled 189 to Lubbers and an article “IM Solutions for Projectiles “Pressure Relief System For Gun Fired Cannon Cartridges,” Crimped to Cartridges for Artillery ApplicationiPhase II, all of which applications are incorporated herein by refer Transition from Cartridge Case Venting to Insensitive Prope ence. liant” by Carl J. Campagnuolo, Christine M. Michienza, 20 Edward G. Tersine, Christine D. Knott, William J . Andrewsi BACKGROUND OF THE INVENTION NDIA IM/EM Symposium, May 11-14, 2009. The Lubbers US. Pat. No. 5,936,189 discloses a cartridge The present invention relates to high velocity automatic munition used with rapid-?re weapons of medium cannon and weapon munitions having a pressure relief sys (about 40 mm). Many such cartridges are received into a tem. 25 that is fed to the rapid-?re weapon. The propulsion chamber 1.0 Introduction: in some cartridge case types are divided into a high-pressure The term “Insensitive Munitions” refers to a generic body chamber (into which the propulsive charge is placed) and a of munitions knowledge that includes guidance practices, low-pressure chamber that is connected with the high-pres regulations, technology, methodologies and standards for sure chamber via exhaust apertures. The cartridge case and complying with the following objective: 30 projectile are mechanically connected via a central threaded “To ensure, to the extent practicable, that munitions under connection that includes an intended break point. Other two development or procurement are safe throughout devel chamber designs (such as the US M430 propulsion) use the opment and ?elding when subject to unplanned stimuli. age-old technique of crimping a cartridge to a projectile. IM are those munitions that reliably ful?ll their perfor When the propulsive charge is ignited in the high-pressure mance, readiness, and operational requirements on 35 chamber by means of a primer (igniter), the propulsive charge demand, and that minimize the probability of inadvert burns and propulsive gases are created at high pressure that ent initiation and the severity of subsequent collateral then act on the projectile base in both chambers. This drives damage to weapon platforms, logistic systems, and per the projectile out of the cartridge case, after the break point sonnel when subjected to selected accidental and com between cartridge case and projectile is broken. A similar bat threats.” 40 cartridge munition is described in Lubbers, US. Pat. No. Insensitive Munitions (“IM”) technology includes new 4,892,038. energetic materials with less sensitivity to unplanned stimuli The US. Pat. No. 7,107,909 and US. Patent Publication as well as mechanical and functional designs that mitigate the No. 2008/0006170 A1, both to Haeselich, disclose another undesired reactions against such unplanned stimuli. Two key concept for venting pressure from the cartridge case of a IM tests required by the US Department of Defense in quali 45 cartridge munition that renders the cartridge’s propulsion ?cation of ammunition are slow cook-off and hot cook-off inoperable. tests where the ammunition is exposed to ?res and the results Notwithstanding these references, however, the pressure are documented. relief concepts disclosed in the prior art generally concern New munition designs should meet the standards for reduc devices for releasing pressure from warheads and rockets. ing the risks of unplanned stimuli creating a catastrophic 50 1.2 Current Concepts and their Limitations: event. There have been various developments of so-called Most prior art references describe venting concepts for “pressure relief” systems or “venting” devices for contained rockets, missiles, mortar rounds and grenade projectiles. explosive and rocket motors. None of the disclosed solutions provides both (1) venting Pressure relief systems in munitions, subject to unplanned projectile cartridge cases in a way that serves as (2) a sound stimuli such as elevated ambient temperatures, must act 55 solution that is usable across a spectrum of automatic before the unplanned stimuli initiates an unacceptable haZ and weapons. Automatic weapons and cannons generally ?re ard. For ammunition, the unacceptable hazard is initiation of high velocity cartridges such as 12.7 mm SLAP, medium a primer that ignites the propellant leading to separation and caliber APDFS projectiles where signi?cant heat and pres ?ight of a projectile. In a worst case scenario, the ?ying sures occur. The required containment of pressure in a car projectile arms and detonates. The IM venting systems work 60 tridge case varies from weapon to weapon. For automatic by venting the propellant, thereby reducing the ef?ciency of weapons, heat is induced (transferred) into the cartridge case propellant combustion (burn) and precluding the ?ight of as the ammunition progresses through ammunition handling, projectiles. Any such pres sure relief system must not interfere which includes storage, feeding, chambering, function ?re, with the normal functioning of that cartridge (munition) when ejection and extraction. In this case, the cartridge case must ?red from a family of automatic weapons. 65 survive intact throughout the entire operational cycle. Large Different solutions for venting devices or pressure relief caliber projectiles (artillery and tank) ?re from fully con systems for IM applications have been designed, tested and tained breach mechanisms. US 8,925,463 B1 3 4 1.2.1 Venting of Cartridge Cases: lique?ed metal or polymer will not be compressed against the Venting devices (IM plugs) with metallic melting plugs in metal surface of a weapon and the unsupported bursting plug the base of the cartridge, such as that described by Haeaelich lacks the structural integrity to contain the propellant burn. in US. Pat. No. 7,107,909, are well suited for low internal When using memory metals, a parallel design challenge pressure cartridges ?red from a single shot 40 mm low veloc occurs. The heated cartridge and IM vent using memory metal ity weapon like a M203 launcher. In this sort of hand feed (where it is held in compression by the automatic cannon’s weapon, the ammunition (1) does not undergo stressful chamber and bolt) must provide adequate structural integrity ammunition handling (feeding, chambering, extraction or to provide for function ?re. ejection), (2) is not exposed to high breach chamber tempera In addition to functioning in the chamber of a hot weapon, tures, and (3) is not extracted inside of an automatic weapon. the cartridge case and IM plug must allow the ammunition to The solution described by Haeselich provides adequate function properly through the entire automatic weapon cycle strength as the pressures are low and the breach provides good (storage, feeding, chambering, function ?re, extraction and containment and physical support of the cartridge case. The ejection). It is important that, after extraction, the IM vent Haeselich design utilizes one or more naked metallic melting does not disintegrate in the automatic cannon or weapon. plugs made of an alloy combination of bismuth, tin (or lead). It is also bene?cial to con?gure memory metal rings or Manufacturing controls of the metallurgy provide for a con bursting plugs that house an i gniter (primer). In con?guring a sistent low temperature melting point (around 140° C.). As “support component” to house the primer, a designer can the metal alloy approaches its melting point, the melting con?gure the primer to optimize physical separation prior to plugs lose their structural strength and cannot withstand the or preventing containment required to effectively ignite pro internal pressure of the high velocity projectile in the normal 20 pellant powders. operation mode of the round (function ?re from an automatic 1.2.2 Automatic Weapon Types, Desire for Common weapon chamber). In addition to or instead of the use of Ammunitions Fired from Different Automatic Weapons, bismuth, tin (or lead), the melting plugs may use polymers. Peak Operating Pressure, Integrity of Cartridges, Variations The use of either bismuth, tin (or lead) alloys may be substi in Weapon Breaches and Cannon/Gun Chambers: tuted with certain polymer plugs. 25 There are signi?cant differences in the design integrity of Nevertheless, in most automatic weapons and cannons a weapons chambers and breaches. Additionally, ammunition naked melting plug (as a method for creating a vent) does not handling system vary from weapon type to weapon type. provide: Medium Caliber ammunition ?res from: (1) adequate structural integrity to the cartridge case. Blow back weapons Structural integrity is particularly important as some 30 Open Bolt weapons cartridges are exposed to heat during ammunition han Gatling Guns dling (storage, feeding, chambering, function ?re, Browning Gun Mechanisms extraction and ejection). During an automatic cannon’s Run Out Gun Mechanisms ammunition handling process, heat will soften fusible Chain Gun (Cannons) IM plugs and additional structural integrity is important 35 Gas Feed Cannons in most automatic weapon/cannon applications; Some weapons completely lock the ammunition into (2) solutions for weapons where heat induced by function sealed breaches, while other weapons may rely on the integ ?ring a cartridge will cause the plug in a cartridge case to rity of the cartridge case to partially contain the propellant disintegrate and foul the feeding of weapons; gases. Chain guns and Gatling guns can be both (self powered (3) for precluding the escape of gases through the melting 40 gas/recoil) and electrically operated. The internal pressure plug in the breach (or bolt). By preventing the breach that higher velocity chambers and cartridges must accommo melting condition, damage to the bolt face (or breach date during normal operation is in the order of 420 Mega block) is prevented; and/or Pascal or higher. FIG. 1 shows the burst pressure inside the (4) optimiZing the physical separation between the primer cartridge case of a 30 mm munition as a function of time. (igniter) and the propellant. 45 Generally, the higher the internal pres sure, the more likely the In many cases automatic weapon and cannon ammunition ammunition will ?re from a sealed broach. A bolt frequently handling include dwell times that require cartridges to rams the cartridge into a chamber or breach providing some undergo an exposure to heat and even undergo chambering in structural support to the base of the cartridge case. Under a hot barrel. Therefore, an effective IM vent must function these circumstances, the ammunition may have some dwell in where automatic ?re has heated the bolt and chamber to near 50 the hot chamber for an automatic weapon. the temperature in which soft metal (bismuth, tin or lead) or a The design relationship (design constraints) among the speci?c plastic polymer undergoes a phase change to a liquid. breach, chamber and cartridge case varies from weapon to When a phase change metal or polymer is used in non-fusible weapon. However, most automatic weapons have the follow bursting plugs, the cartridge case can retain adequate struc ing steps of in ammunition handling (SFCFFEE): tural integrity (support) as the outer walls of the cartridge case 55 Storage are supported by the weapon chamber. The rear of the car Feeding tridge case is typically supported by a bolt that chambers the Chambering cartridge into a chamber (or breach). Seals and the geometric Function Fire con?guration can provide integrity to the cartridge walls Extraction while the melted metal or polymer is in compression. This 60 Ejection con?guration, an example of which is illustrated in FIG. 16, The following Table describes steps A-G generally used in allows the lique?ed metal or polymer, encapsulated by a automatic cannon feeding systems (operations). The design non-fusible material, to provide structural integrity as the IM criteria for steps A-D entail the cartridge case providing bursting plug, while liquid, is in compression during function adequate strength and integrity to provide good sealing and ?re. Conversely, when a cartridge with the IM vent described 65 function in the cannon’s chamber. Once ?red, the design herein is heated in an unsupported situation (not in a breach or requirement shifts in that the “heated” IM plug must retain held by a bolt), the IM vents will burst as intended as the adequate structural integrity to preclude disintegration of the US 8,925,463 B1 5 6 IM plug (spilling the melted contents into the weapon). In the a broad compatibility in multiple weapon types. This gener case where a memory alloy (or a mix of melting plug and ally requires that a cartridge case retains varying degrees of memory alloy) is provided, the IM plug must not disintegrate. structural integrity as it undergoes ammunition handling. For

Automatic Weapon Function Fire Heat Condition During Ammunition Step Time Steps Handling and Operation

A T0—T1 Exposure of Ammunition to If outside a vehicle, ammunition box is heated by the sun. heat in an ammunition box If inside a vechile heat from vehicle operating components (Note 1) frequently transfer heat to cartridges in an ammunition box. B T1—T2 Feeding of Ammunition As ammunition nears the heated chamber of a weapon, components into a breach in the ammunition handling sysytem transfer heat into a cartridge. C T2—T3 Ammunition dwell in a Closed bolt/breach designs chamber a cartridge where that cartridge chamber or bolt face can be in a ready position waiting for function ?re. In this condition, (see note breach construction) heat (from prior cartridges ?red) will heat a cartridge. With open bolt designs a cartridge case is attached to a bolt face. For recoil operated weapons, ammunition, bolt and breach move in a synchronized fashion. D T3—T4 Function Fire The ignition of propellant transfers signi?cant heat into the cartridge case. E T4—T5 Extraction Ammunition handling systems extract the spent cartridge from the cartridge case. At this point, the cartridge case is a heat sink carrying a hot spent cartridge from a weapon. The cartridge is under high g forces as it is removed from the weapon and mechanical components extract the cartridge case via various well known ammunition handling methadologies F T5—T6 Ejection Ammunition is ejected from the weapon. It is generally desirable that the ammunition does not disintegrate in a manner that would foul the weapon or create a safety concern. G T6—T7 Collection of Spent Cartridge The cartridge case cools as it moves through the air and lodges Cases against a cooler ambient surface.

30 Note 1: During step T2-T4 various breach designs heavily NATO countries, automatic weapon and cannon caliber in?uence the required structural strength of a cartridge case. ammunition is generally identi?ed as ammunition in the fol Note 2: Increasing heat is transferred to the projectile and lowing diameters: 20 mm, 25 mm, 30 mm. Some products cartridge case as the ammunition undergoes ammunition han like the 12.7 mm (.50 cal) and 40 mm AGLs are cross-over dling (StepsA-C) in an automatic weapon. Function ?re (Step 35 weapons that can be described as heave machine guns. In D) imparts a signi?cant amount of heat into the cartridge case. some cases, different cartridge case lengths are applicable to The cartridge case’s structural strength required for Steps different . The following paragraphs provide a sum A-D depends on the design of a breach construction. The mary of the principle cannon weapons in US/NATO: structural integrity after ?ring (Steps E and F) must preclude 40 1.2.2.1 .50 cal (12.7 mm): disintegration of components in an automatic weapon that may affect weapon function. Additionally, depending on the The famous .50 cal family of weapons is one of the oldest designs still in widespread use worldwide. Two weapons location where spent cartridge cases are collected, it may be dominate the market. desirable that debris is minimized so users may wish that spent cartridge cases do not disintegrate even after ejection. 45 Note 3: In Stops A-C the cartridge case should retain Weapons/Cannons Firing 12.7 mm x 99 Ammunition adequate structural integrity until function ?re where the projectile separates from the cartridge case venting gases and Weapon propelling the projectile. Nomenclature Weapon Type (Rounds Per minute) Note 4: In Step D the cartridge case should retain adequate 50 structural integrity so that IM plugs (supported by the cham Recoil Operated 450—635 ber or breach walls or bolt face) do not fail. The IM plugs GAU 21 (M3M) Recoil Operated 6000 rpm should not fail in compression. Note 5: In Steps E and F the cartridge case no longer must 1.2.2.2 20 mm Cannons: retain the strength of structural integrity required up to func 55 tion ?re; however, the cartridge should still retain adequate Two types of cartridges dominate the 20 mm cannon mar structural integrity so that the plug does not disintegrate as ket; namely, 20 mm><102 and 20 mm><139. undergoes the ammunition handling steps of extraction and ejection. Further, it is very important that melted plug mate rial does not adhere to weapon components where it could 60 Weapon Rate of Fire Nomenclature Weapon Type (Rounds Per minute) foul the weapon or create stoppages. Note 6: In Step G it is generally desirable that spent car Weapons Cannons Firing 20 mm x 102 Ammunition tridge cases retain their integrity so that are easily collected M197 Gatling 730 rpm for disposal. The disintegration of materials could create haZ M61 Vulcan Gatling Gun 6000 rpm ardous edges and surfaces. 65 M621 Giat Blow Back 800 rpm The variation in weapon designs and need for automatic cannon and weapon ammunition capable of being ?red from US 8,925,463 B1 8 -continued fully chambered at the time of primer ignition. An MK47, on the other hand, ?res from a closed bolt (at a slower rate of ?re) Weapon Rate of Fire so ammunition ?red from the MK47 has a longer dwell time Nomenclature Weapon Type (Rounds Per minute) in a heated chamber (breach). It is also important to realize Weapons/Cannons Firing 20 mm x 139 Ammunition that some weapons (like the MK19) do not automatically eject the last spent cartridge case on a belt (the last cartridge KAD Oerlikon Gas or Blowback 600—850 rpm remains on a hot bolt face). (formerly the Hispano— Suiza HS. 820) M683 GIAT Delayed Blowback 720 rpm MK 20 Rh 202 Gas Operated 880—1,000 rpm Weapons Firing 40 mm x 53 Ammunition (High Velocity 40 mm) Rheinmetall MK19 Blow BacldOpen Bolt 325—375 rpm (advanced primer ignition) 1.2.2.2 25 mm Cannons: MK47 Closed Bolt 250—300 rpm H&K Blow BacldOpen Bolt 350 rpm 25 mm like most cannon calibers must ?re from many (advanced primer ignition) different types of Weapons/cannons with very different heat pro?les, dwell times and ammunition handling systems. 1.2.2.5 Ammunition Standardization for Automatic Can nons and Weapons:

Weapons/Cannon Firing 25 mm x 137 Ammunition One should note, as illustrated in the tables above (.50 cal, 20 20 mm, 25 mm, 30 mm and 40 mmAGLs), that the weapon Weapon Rate of Fire rates of ?re vary greatly within each ammunition caliber Nomenclature Weapon Type (Rounds Per minute) family. NATO standardization is discussed below in para M242 Bushmaster Chain Gun 200—500 rpm graph 1.3. With the large variation in rates of ?re among GAU—12 Equalizer Gatling Gun 1800—4200 rpm automatic weapon families, one will recognize that the heat Oerlokon KBA 80281 Gas—operated 200—600 rpm 25 produced in higher rate weapons is much greater than the heat (Rheinmetall) weapon produced in weapons with lower ?ring rates. In an environ GIAT 25M811 Externally Powered 125—400 rpm Cam Arrangement ment where standardized ammunition is required to function from multiple weapons, an effective IM vent for medium caliber ammunition must provide for (1) venting functions in 1.2.2.3 30 mm Cannons: 30 slow and hot cook-off, and (2) while functioning across a 30 mm weapons provide a useful example of the desire for spectrum of weapons with different times, different standardized ammunition (within NATO) that guides ammu dwell times, where cartridges undergo different g loads as the nition design. There are two types of 30 mm cannon car cartridge case undergoes the storage, feeding, chambering, tridges in US DoD service 30 mm><173 and 30 mm><113. function ?re, extraction and ejection. When considering IM 35 ammunition solutions for ammunition ?red from automatic weapons and cannons, the Haeselich design, as disclosed in Weapons/Cannons Firing 30 mm x 173 Ammunition the aforementioned U.S. Pat. No. 7,107,909, is inadequate. The design is not robust enough in providing structural integ Rate of Fire Weapon Nomenclature Weapon Type (Rounds Per minute) rity to function from automatic weapons and cannons. For 40 automatic cannon/weapon ammunition, the design require GAU 8 Avenger Gatling Gun 4200 rpm ments are further explained herein. Bushmaster Chain Gun Chain Gun 200 rpm Rheinm 30—1/2 Gas Operated Weapon 700 rpm 1.2.3 Heat Transfers, Chamber Dwell Time and Ammuni tion Handling: Some systems, such as turrets in ?ghting vehicles, often In many gas operated weapons (like the Rheinmetall 30-1/ 45 have ammunition feed systems where the ambient “ready” 2) proper venting of gases is paramount to operation of the ammunition is exposed to high temperatures. Many closed weapon. (unsealed) bolt weapon designs rapidly transfer heat into cartridge cases. Weapons such as the .50 cal Browning and certain artillery types have cook-off dangers where hot bar Weapons/Cannon Firing 30 mm x 113 Ammunition 50 rels rapidly transfer heat to their cartridge cases. Some weap ons also have slow rates of ?re with extensive dwell times in Weapon Rate of Fire Nomenclature Weapon Type (Rounds Per minute) a chamber. One should also note that the surface (contact area) of “hot” ammunition handling surfaces effect the heat ADEN MK4 Recoil (electric primer) 1200—1700 rpm transferred into cartridge cases. The heat produced by previ M230 Chain Gun 625 rpm 55 ous salvos is transferred into automatic weapons. Accord ingly, the cartridge case and IM vent design must accommo 1.2.2.4 40 mmAGLs: date heat transfer into the cartridge case during storage, 40 mm Automatic Grenade Launchers (AGLs) like the feeding, chambering, function ?re, extraction and ejection. MK19 and MK47 are cross-over weapons. 40 mm AGLs do 1.2.3.1 IM Function: not ?re with the energy of cannons, but the weapons do ?re 60 The melting temperature of the meltable metallic or poly ammunition at a rate of ?re of 250-375 rounds per minute. mer plugs must be equivalent to the temperature induced by a The MK19 that uses an open bolt with advanced primer heating of a ?re (slow cook-off or fast cook-off testing). ignition only the part of the un-chambered cartridge provides Alternatively, the use of memory metal alloy alone or in structural integrity. An MK47, ?ring the same cartridge, is a combination with a memory metal alloy should provide for short recoil operating system ?ring from a closed bolt. There 65 venting from the cartridge case at a temperature that is lower fore, the MK19’s cartridge case requires greater structural than that of the auto-ignition in the primer (i gniter), ?ash tube integrity for ?ring than the MK47 as the cartridge case is not or propellant charge. Heat transfer and elapsed time in?uence