专利US8443730B2

1、公开号:US8443730B2 专禾I名称:HIGH STRENGTH POLYMER-BASED CARTRIDGE CASING ANDMANUFACTURING METHOD 公开日:May 21,2013 国际分类:F42B 5/SO (2006.01) 申请号:13/350,607 申请日:Jan. 13, 2012 发明人:Charles Padgett, Orlando, FL (US) 申请人:PCP Tactical, LLC, Vero Beach, FL (US) 优先权号:US 2012/0180688 A1 Jul. 19, 2012同族专利:发明摘要:A high

2、strength polymer-basedcartridgecas ing can in elude a first endhav ing amouth and a neckexte ndingaway from the mouth. Next, ashoulderexte nds below theneck andaway from the first end. Thecartridgedischargecan be have a fran giblep orti oncap able of being sp lit upon of a projectile. The shoulder c

3、an have unequal outside and in side shoulder an gles. The cas ing can also in clude an insert hav ing a rim at one end or a plurality of ribs extending Iongitudinally along a wall betwee n the shoulder and the bottom of the cartridge and sp aced radially from each other around a circumferenee of the

4、 wall. A projectile canbe dis posed in the mouth and a relief can be dis po sed on the n eck n ear the mouth and p rojectile. The relief can form a gap betwee n the n eck and the projectile to receive an adhesive.发明领域（关键词）:The present subject matter relates to ammunitionarticles with plasticcomponen

5、ts such as cartridge casing bodies, and, more particularly,to making ammun iti on articles with ribs, a variable width shoulder, an in sert, and fran gible n eck.发明背景:It is well known in the in dustry to manu facture cartridge cases from either brass or steel. Typi cally, in dustry desig n calls for

6、 materials that are strongeno ugh to withsta ndextreme op erat ingp ressures and which can be formed in to a cartridge case to hold the bullet, while simulta neously resist rup turi ng duri ng the firing p rocess.Conven ti onal ammun iti on typi cally in cludes four basic componen ts, that is, the b

7、ullet, the cartridge case hold ing the bullet there in, a prop ella nt usedto push the bullet down the barrel at predeterminedvelocities, and a p rimer, which pro vides the spark n eeded to ign ite the po wder which sets the bullet in motio n dow n the barrel.The cartridge case is typ ically formed

8、from brass and is con figured to hold the bullet therein to create a p redeterm ined resista nee, which is known in the in dustry as bullet p ull. The cartridge case is also desig ned to contain the prop ella nt media as well as the p rimer.However, brass is heavy, expensive, and potentiallyhazardou

9、s. For exa mple, the weight of .50 caliber ammun iti on is about 60 pounds per box (200 cartridges plus lin ks).The bullet is con figured to fit withi n an open end or mouth of the cartridge case. Certain bullets, mainly for non-military uses, can include a groove (here in after referred to as a can

10、n elure) formed in the mid sect ion of the bullet to acce pt a crim ping acti on imp arted to the metallic cartridge case therei n. When the crim ped p orti on of the cartridge case holds the bullet by lock ing in to the cann elure or onto the diameter, a bullet p ull value isprovidedrepresentinga p

11、redeterminedtension at which the cartridge case holds the bullet. The bullet pull value, in effect, assists imparting a regulated pressure and velocity to the bullet when the bullet leaves the cartridge case and travels dow n the barrel of a gun.Furthermore, the bullet is typi cally manu factured fr

12、om a soft material, such as, for example only, lead. The bullet is accepted into the mouth of the cartridge, and the n the cartridge alone is crim ped to any p orti on of the bullet to hold the bullet in p lace in the cartridge case. Though, typi cally, the cartridge case is crim ped to the cann elu

13、re of the bullet.However, one drawback of this desig n is that the crim ped n eck does not release from around the bullet eve niy whe n fired. This is p artly due to thefact that the brass casing is not manufacturedperfectly.The material thick ness around the n eck is slightly differe nt caus ing th

14、e case to deform at slightly differe nt rates thus allow ing the bullet to be p ushed slightly off cen ter whe n coming out. This leads to un certa in p erforma nee from round to round. Pressures can build up uneveniy and alter the accuracy of the bullet.The propellantis typically a solid chemical c

15、ompound in powder form commo nIy referred to as smokeless po wder. Prop ella nts are selected such that whe n confined with in the cartridge case, the prop ella nt bums at a known and p redictably rapid rate to p roduce the desired expanding gases.As discussed above, the expanding gases of the prop

16、ella ntpro vide the en ergy force that la un ches the bullet from the gras p of the cartridge case and prop els the bullet dow n the barrel of the gun at a known and relatively high velocity.The primer is the smallest of the four basic components used to form conven ti onal ammun iti on. As discusse

17、d above, p rimers pro vide the spark n eeded to ign ite the po wder that sets the bullet in moti on dow n the barrel.The primer includes a relatively small metal cup containing a priming mixture, foil paper, and relatively small metal p ost, commo niy referred to as an an vil.When a firing pin of a

18、gun or firearm strikes a casing of the p rimer, the an vil is crushed to ign ite the priming mixture contained in the metal cup of the primer. Typically, the primer mixture is an explosive lead styphnateblended with non- corrosive fuels and oxidizers which burns through aflash hole formed in the rea

19、r area of the cartridge case and ignites thepropellantstored in the cartridge case. In addition to ignitingtheprop ella nt, the p rimer p roduces an in itial p ressure to support the burningprop ella ntand seals the rear of the cartridge case top reve nthigh-p ressure gases from esca ping rearward.

20、It should be no ted that it iswell known in the industry to manufactureprimers in severaldiffere ntsizes and from differe nt mixtures, each of which affects ign iti on differe ntly.The cartridge case, which is typically metallic, acts as a payloaddeliveryvessel and can have several body shapes and h

21、ead configurations,depending on the caliber of the ammun iti on. Desp ite the differe nt bodysha pes and head con figurati ons, all cartridge cases have a feature used toguide the cartridge case, with a bullet held there in, into the chamber of thegun or firearm.The p rimary objective of the cartrid

22、ge case is to hold the bullet, p rimer,and prop ella nt there in un til the gun is fired. Upon firing of the gun, thecartridge case seals the chamber to p reve nt the hot gases from esca pingthe chamber in a rearward direct ion and harm ing the shooter. The emptycartridge case is extracted manu ally

23、 or with the assista nee of gas or recoilfrom the chamber once the gun is fired.As show n in FIG. 1A, a bottle neck cartridge case 10 has a body 11 formedwith a shoulder 12 that tapers into a n eck 13 hav ing a mouth at a first end.Note that the shoulder 12 has a uniform thick ness, or width. Furthe

24、r, theangle of the shoulder 12 on the outside of the cartridge case 10 is thesame as the an gle of the shoulder12 in side the case 10, deno ted as a andresp ectively .In the p rior art, a=0, and the shoulder an glea is dictated bythe caliber of the cartridge. A p rimer holdi ng chamber 15 is formed

25、at asec ond end of the body opp osite the first end. A divider 16 sep arates amai n cartridge case holdi ng chamber 17, which contains a prop ella nt, fromthe p rimer holdi ng chamber 15, which com muni cate with each other via aflash hole cha nnel 18 formed in the web area 16. An exteriorcircumfere

26、ntial region of the rear end of the cartridge case includes anextracti on groove 19a and a rim 19 b.Prior art p ate nts in this area in clude U.S. P at. No. 4,147,107 to Ri ngdal, U.S.Pat. No. 6,845,716 to Hussei ni et al., U.S. P at. No. 7,213,519 to Wiley etal.,an dU.S. Pat. No. 7,610,858 to Chu n

27、g. The four p ate nts are directed to anammun iti oncartridge suitable for rifles or guns and in clud ing a cartridge case made ofat least a pl astics material. However, each has their own drawbacks.Further, a technical report released in May 2005 bythe ArmamentResearch, Devel opmentand Engin eeri n

28、gCen ter titled“ Alter nativeCartridge Case Material and Desig n ” by J.S. Chung, et al. (the “ Chung Paper ” ) describes in detailthe failings ofcerta in poly mers used in ammun iti oncartridges and cartridge desig nsknown to the authors. Features and limitati ons are ide ntified for cartridge, the

29、 poly mer, and the moldi ng p rocess. Many drawbacks are no ted.Hence a n eed exists for a poly mer cas ing that can p erform as well as orbetter tha n the brass alter native.A further impro veme nt are polymercas ings that are cap able of p roducti on in a more conven ti onaland costeffective manne

30、r, i.e. by using standardloading presses and better manu facturi ng tech niq ues.发明概述:The teach ings here in alleviate one or more of the above no ted p roblems with the stre ngth and formati on of poly mer based cartridges.A high stre ngth poly mer-based cartridge cas ing in closi ng a 25 volume, c

31、an in clude a first end hav ing a mouth, a n eck exte nding away from the mouth, and a shoulder exte nding below the n eck and away from the first end. A proj ectile can be dis posed in the mouth and a fran gible p orti on can be dis posed on the n eck, which is cap able of being sp lit upon dischar

32、ge of the p rojectile. In an exa mp le, the sp lit of the fran gible p orti on p reve nts a sec ond p rojectile from being dis posed in the mouth.The fran gible p orti on can be, at least, a cut-out, a reduced thick ness of the n eck, a scall op in the n eck, or a p erforated seam. The fran gible p

33、orti on can be dis po sed on an in side or outside of the cas ing, and can exte nd to app roximately the shoulder.A method of mak ing a high stre ngth poly mer-based cartridge cas ing canhave the ste ps of mold ing a component using a poly mer. The mold ing ste pcan in clude mold ing a first end hav

34、 ing a mouth and a sec ond end opp ositethe first end. Ste ps also in clude moldi ng a n eck exte nding away from themouth, moldi ng a shoulder exte nding below the n eck and away from thefirst end; and forming a fran giblep orti onon the n eck cap able of beingsplit.The method may have the step of

35、forming at least one of a cut-out, areduced thick ness of the n eck, a scall op in the n eck, or a p erforated seamand forming the fran giblep orti on on an in sideor outside of the neck.Further, the frangibleportioncan be formedapp roximately to theshoulder.A high strength polymer-basedcartridgecas

36、ingcan include, in anotherexa mple, a first end hav ing a mouth and a n eck exte nding away from themouth. Next, a shoulder exte nds below the n eck and away from the firstend. Below the shoulder, any of the below exa mp les of cartridges can beformed or any type of poly mer cartridge can be formed

37、incorpo rat ing theforthcomingexample of a shoulder. However, the shoulderin cludes anoutside shoulder sloped at an outside shoulder angle inrelationto acen ter axis exte ndingIon gitud in allyalong the cartridgeand p ass ingthrough a cen ter of the mouth. Also, an in side shoulder issloped at anin

38、side shoulder an gle in relati on to the cen ter axis. The in side shoulder issep arated from the outside shoulder by a shoulder thick ness. Further, theoutside shoulder an gle and the in side shoulder an gle are not equal.Additi on ally, the in side shoulder does not con tact the p rojectile in the

39、 n eck of the cartridge.The in side shoulder an gle can be greater tha n the outside shoulder an gle or less tha n the outside shoulder an gle.Further, the shoulder can have a shoulder thick ness formed betwee n the outer shoulder and the inner shoulder and the shoulder thick ness can vary along len

40、 gths of the inner and outer shoulders.A method of mak ing a high stre ngth poly mer-based cartridge cas ing caninclude the steps of molding a component using a polymer.The component hav ing a first end hav ing a mouth and a sec ond end opp osite the first end. Further ste ps can be mold ing a n eck

41、 exte nding away from the mouth and moldi ng a shoulder exte nding below the n eck and away from the first end. The ste ps of mold ing the shoulder can in clude forming an outside shoulder sloped at an outside shoulder an gle in relati on to acen ter axis exte ndingIon gitud in allyalong the cartrid

42、ge and p ass ing through a cen ter of the mouth and forming an in side shoulder sloped at an in side shoulder an gle in relati on to the cen ter axis, and sep arated from the outside shoulder by a shoulder thick ness. Ano ther ste p is sett ing the outside shoulder an gle to not equal the in side sh

43、oulder an gle. Additi on ally, the in side shoulder is formed un iform over the en tire circumfere nee of the cartridge.In additionto the above method, the setting step can further include sett ing the in side shoulder an gle less tha n the outside shoulder an gle or of sett ing the in side shoulder

44、 an gle greater tha n the outside shoulder an gle.A shoulder thick ness can be formed betwee n the outer shoulder and the inner shoulder. Furthermore, the forming the shoulder thickness can in clude a ste p of vary ing the shoulder thick ness along len gths of the inner and outer shoulders.A further

45、 exa mple of a high stre ngth poly mer-based cartridge cas ing can include an upper component, molded from a polymer. The upper component hav ing a first end hav ing a mouth, at least a wall betwee n the first end and a sec ond end of the upper component opp osite the first end.and an overla p p ort

46、i on exte nding from the wall n ear the sec ond end. The cas ing also has a lower component, molded from a poly mer, i nclud ing a tap ered p orti on that en gages the overla p p orti on to join the upper and the lower componen ts, an outer sheath dis posed opp osite the tap ered p orti on, and a lo

47、wer bowl dis po sed betwee n the tap ered p orti on and the outer sheath has a hole therethrough. Further in cluded is an in sert hav ing a rim disposed at one end of the insert, an overmolded area formed oppo site the rim and en gagi ng the outer sheath to join the in sert to the lower component an

48、d a ring formed on an in side of the overmolded area and exte nding into the hole of the lower component.The in sert can also in clude a ridge formed on the overmolded area and a key formed on the ridge, where in both the ridge and the key en gage the outer sheath.The exa mple of the lower component

49、 of the high stre ngth poly mer-based cartridge cas ing above also contains a seat formed on the tap ered p orti on.and a bottom end of the ribs con tact the seat. Further, the lower bowl and the outer sheath can comp ress aga inst a p orti on of the overmolded area whe n un der p ressure.Alter nate

50、ly, a len gth of the upper component can greater tha n a len gth of the lower component or the len gth of the lower component can be greater than the len gth of the upper component.Anotherexample of a high strengthpolymer-basedcartridge casing in cludes an upper component, molded from a poly mer, an

51、d hav ing a first end hav ing a mouth, at least a wall betwee n the first end and a sec ond endof the upper componentoppositethe first end, a sleeve extendingIon gitud in ally and radially about the wall, and at least one of an overla p p orti on and an un derskirt p orti on exte nding from the wall

52、n ear the sec ond end. The lower component is molded from a polymerand includes at least one of a tapered portion and an outer taperedportionthat engages at least one of the overlap portionand theunderskirtportions,respectively,to join the upper and the lowercomponents.A method of mak ing a high str

53、e ngth poly mer-based cartridge cas ing canin clude the ste ps of mach ining an insert hav ing a p rimer po cket, a flashhole, a ring, and an overmolded area. The a lower component can the nbe molded using a polymer having the steps of molding the polymerover the overmolded area of the insert and st

54、opping the flowof thepoly mer at the ring. The upper component can be mold ing an using thesame, or differe nt, poly mer. The upper component has a first end hav inga mouth and a second end oppositethe first end. Lastly, thelowercomponent can be bon ded to the upper component at the sec ond end.A ye

55、t further exa mple of a high stre ngth poly mer-based cartridge cas ingcan include an upper component, molded from a polymer. Theuppercomponent hav ing a first end hav ing a mouth, at least a wall betwee nthe first end and a sec ond end of the upper component opp osite the firstend, a plu rality of

56、ribs exte nding Ion gitud in ally about a len gth of the walland sp aced radially from each other around a circumfere nee of the wall,and an overla p p orti on exte nding from the wall n ear the sec ond end. Thecas ing also has a lower component, molded from a poly mer, i ncludi ng atap ered p orti

57、on that en gages the overla p p orti on to join the upper and the lower componen ts, an outer sheath dis posed opp osite the tap ered p orti on, and a lower bowl dis posed betwee n the tap ered p orti on and the outer sheath has a hole therethrough. Further included is an insert hav ing a rim dis posed at one end of the in sert and an overmol