mil-g-71047 (ar) military specification

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IEz.E5JMIL-G-71047 (AR)13 April 1993

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MILITARY SPECIFICATION

This specification is approved for use by the U.S. Am Armament,Munitions and Chemical Command, and is available for use by allDepartments and Agencies of the Department of Defense.

1. SCOPE

1.1 Scope. This specification covers the requirements,examinations and tests for an automatic, recoil operated, air-cooled, caliber .5o machine gun (see 6.1).

2. APPLICABLE DOCUMENTS

2.1 Government documents.

2.1.1 Specifications, standards, and handbooks. Thefollowing specifications, standards, and handbooks form a part ofthis document to the extent specified herein. Unless otherwisespecified, the issues of these documents are those listed in theissue of the Department of Defense Index of Specifications andStandards (DODISS) and supplement thereto, cited in thesolicitation (see 6.2) .

Beneficial comments (recommendations, additions, deletions)and anypertinentdata whichmay be of use in improvingthisdocument,shouldbe -addressedto: Commander,U.S. Army A.RDEC,ATTN: SMC&R-BAC-S, PICatlnnY

Arsenal,New Jersey07806-5000by using the self-addressed StandardizationDocumencImprovementProposal(DDForm 1426)appearin9at the end of ‘hisdocumentor by letter.

AMsc H/.% FSC 1005DISTRIBUTION STATEMENT A. Approved-for$p#blicrelas%d~klributionisu~@ed.

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MIL-G-71047 (AR)

SPECIFICATIONS

MILITARY

MIL-W-13855

MIL-P-14232

MIL-I-45607

MIL-W-63150

STANDARDS

MILITARY

MIL-STD-109MIL-STD-130

MIL-STD-1949

.Weapons: Small Arms and AircraftArmament Subsystems, GeneralSpecification forParts, Equipment and Tools for ArmyMateriel, Packaging and Packing ofInspection Equipment, Acquisition,Maintenance and Disposition ofWeapons and Support Material, StandardQuality Assurance Provisions for

Quality Assurance Terms and DefinitionsIdentification Marking of US MilitaryPropertyInspection, Magnetic Particle

(Unless otherwise indicated, copies of federal and militamspecifications, standards, and handbooks are available fro~ theStandardization Documents Order Desk, Bldg. 4D, 700 RobbinsAvenue, Philadelphia, PA 19111-5094. )

2.1.2 Other Government documents, drawinqs, andpublications . The following other Government documents,drawings, and publications form a part of this document to theextent specified herein. Unless otherwise sDecified, the issuesare those cited in the solicitation.

DILMdINGS (see 6.4)

U.S. ARMY ARMAMENT RESEARCH, DEVELOPMENTCENTER (ARDEC)

PRODUCT AND PACKAGING DRAWINGS

AND ENGINEERING

12949648 - Machine Gun, Cal. 50, XM296PS 12949648 - Packaging Data Sheet, Machine Gun, Cal

.50, XM296

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MIL-G-71047 (AR) ““’

INSPECTION EQUIPMENT DRAWINGS

!5520627 -

6047008 -7270150 Or

6511053 -8440920 -8440929 -11838715 -12003958 or

5351211 -12003959 or

5351213 and5351214 -

12011$345 -

Copper Compression Cylinder HoldingFixture .Xndicator Gage Assembly

Weighing GageCylinder, Pressure GageFixture, Function FiringBoxesight Kit

Gage, Iieadspace

Gage, TimingDiagram, Targeting and Accuracy

PUBLICATIONS

TECHNICAL MAkJUAL

TM 9-1090-214-23T - Armament Subsystem Helicopter,XM149, .50 Caliber Machine GunXFf296 (12.7mm) 2.75 Inch (70mm)Rocket System with Missile System .Integration

(Copies of other Government documents, drawings, and pu~licationsrequired by contractors in connection with specific acquisitionfunctions should be obtained from the contracting activity or as‘directed by the contracting activity.)

2.2 Order of precedence. In the event of a conflictbetween the text of this document and the references citedherein, the t-t of this document takes precedence. Nothing inthis document, however, supersedes applicable laws and .regulations unless a specific exemption has

3. REQIJIREM2NTS

3.1 First article. When specified inpurchase order (see 6.2), a sample shall be

been obtaine~.

the contract orsubjected to first

article inspection in accordanc~ with the technical provisionsherein (see 4.3). Unless otherwise specified (see 6.2), thefirst article shall include the Pilot Pack (see 5.1).

3.2 Materials, construction and desiqn. The machine guncomponents and assemblies shall conform to the material con-struction and design requirements specified herein, on Drawing12949648 and the applicable part and assembly drawings, and inMIL-W-13855.

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MIL-G-71047 (AR)

3.2.1 Sear enqaqement. The cocking lever, when operated byhand, shall retract the firing pin exchange assembly sufficientlyto insure engagement of the hook of the extension to the hook ofthe sear.

3.2.2 Firinq pin protrusion. The firing pin protrusionshall not be less than 0.072 inch and not be more than 0.079 inchwhen measured from the breech face.

3.2.3 Headspace. Each machine gun shall be capable ofbeing adjusted for proper headspace. With the bolt retracteduntil the barrel extension and the trunnion block are separatedapproximately 1/16 inch, the distance between the rear face ofthe barrel and the face of the bolt shall not be more than 0.206inch and not be less than 0.202 inch.

NOTE : This adjustment is essential for proper weapon functionand must be maintained during all firi.ncjschedules.

3.2.4 Timina. After having been adjusted for headspace,each machine gun must then be timed. The firing pin shall notrelease upon actuation of the triggering mechanism when the gapbetween the barrel extension and the trunnion block exceeds 0.116inch. However, at some point in the interval when the gapbetween the barrel extension and the trunnion block is not more“than 0.116 inch and not less than 0.020 inch, the firing pinshall release upon actuation of the triggering mechanism.

NOTE : This setting must also be maintained during subsequentfiring schedules.

3.3 Phvsical characteristics.

3.3.1 Weiqht. The machine gun without any type of flash orblast suppressor attachment on the barrel shall not weigh morethan 65 lbs.

3.3.2 Dimension. The machine gun without any type of flashor blast suppressor attachment on the barrel shall not exceed57.00 inches in length, 4.00 inches in width, and 6.75 inches inheight .

3.4 Performance characteristics.

3.4.1 Firinq pin release. The firing pin shall be releasedby a load not exceeding 38 pounds applied to the sear slide andby a load not exceeding 26 pounds applied to the sear. Testingshall be as specified in 4.5.5.

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MIL-G-71047 (AR)

3.4.2 Firin~ Din indent. The firing pin indent shall bewithin the range of 0.017 co 0.023 inch and shall not be offcenter more than one-half the diameter of the indent. ,Testingshall be as specified in 4.5.6. .

3.4.3 Hiah cxessure resistance. The machine gun shall becapable of withstanding the firing of one round of Governmentstandard .50 caliber, Ml high pressure tes~ cartridge. Partsshall be free of cracks, seams or other injurious defects afterproof firing. The barrel assembly, barrel extension assembly,bolt subassembly and receiver assembly, of machine guns, aftersatisfactorily meeting this requirement, shall be proof marked asspecified on the appropriate drawings. Testing shall be asspecified in 4.5.7.

3.4.4 Functioning. The machine gun shall function withoutmalfunctions attributable to Che weapon, and without evidence ofunserviceable parts. Testing shall be as specified in 4.5.8.

3.4.5 Belt lXll~. The machine gun shall be capable offunctioning while a 20 pound free hanging weight is attached tothe ammunition belt. Testing shall be as specified in 4.5.S’.

3.4.6 Cyclic rate of fire. The machine guns shall maintainan average rate of fire of 700 to 800 shots per minute. Testingshall be as specified in 4.5.10.

3.4.7 Tar~etina and accuracy. With the boresight reticlealigned with the center of the target of Drawing 12011845, the

.center of impact of each 50 round burst shall be within an 8.0intihdiameter circle as shown on the drawing and 80% of the shotsshall group within or cut the edge of that 8.0 inch diametercircle at range of 1,000 inches. Testing shall be as specifiedin 4.5.11.

3.4.8 Endurance. The machine gun shall be capable offiring an endurance schedule of 10,000 rounds of M33 ballcartridges, using M9 links, without substitution of anycomponents and without malfunctions in =cess of the limits shown .in Table I. ~ Testing shall be as specified in 4.5.12.

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MIL-G”71047 (AR)

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TABLE I. Malfunctions and unserviceable components (see Notes) .

Number permitted inthe 10,000 round

Malfunctions (attributable to gun)x endurance test

Extruder primer 1Failure to eject 1Failure to extract (cartridge case

from chamber) 1Failure to extract (cartridge from

feed belt) 1Failure to feed (bullet striking face

of barrel) 2Failure to feed (insufficient recoil) 1

Hangf$re (noticeable) (See 4.5.3.12) oMisfire caused by light blow

(See 4.5.3.12) 2Pierced primer 1Uncontrolled fire oAll other malfunctions:

If correctable by recharging 3If not correctable by recharging 1

NOTE : 1 When malfunctions (within the allowances of Table I)are traceable to particular components, it ispermissible to replace such compments and record themas unserviceable, subject to limitations of Table I.When it is definitely established by the inspector thatpreviously recorded malfunctions are attributable to anunserviceable component, such malfunctions shall not becounted against the machine gun being tested, providedthat they occurred not more than 200 rounds prior toreplacement of the unserviceable component. However,such malfunctions shall remain recorded and properlyidentified.

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MIL-G-71047 (AR) “’”

TABLE I. Malfunctions and unsemiceable components (see Notes) .

(continued).

Number permitted inthe 20,000 round

Unserviceable components ‘ endurance te~z~

Accelerator oBack plate oBarrel extension oBarrel support oBelt feed pawl oBelt feed slide oBolt oBreech lock cam oCocking lever oCover pin “ - 0Driving springs (inner and outer) oEjector 1Extrac&or oExtractor cam oFiring pin 1Firing pin spring oSear 1Set back of recoil plate in face of bolt

(in excess of .0002 inch) oSide, top, or bo~tom plates

(receiver assetily) oAll other unserviceable components

(different) 2

NOTE:; 2 NO unserviceable components shall be allowed-withinthe first 5,000 rounds.

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MIL-G-71047 (AR) ““

3 .4.8.1 Barrel erosion. The barrel assembly shall becapable of firing a 10,000 round endurance schedule withoutexperiencing a muzzle velocity drop of more than 200 feet persecond. Testing shall be as specified in 4.5.13. .

3.5 Interchanqeabilitv. Unless otherwise specified on thedrawings, all parts shall be interchangeable. (In manual

assembly operations, there shall be no objections to preferentialassembly of part provided that all parts are dimensionallyacceptable. ) Testing shall be as specified in 4.5.14..,

3.6 Markinq. Each machine gun and each component thereoffor which markings are prescribed, shall be clearly marked inaccordance with the drawings and MIL-STD-130. Each machine gun

shall be identified by a se<ial ntqnber assigned by the procuringactivity (see 6.1) . ‘

3.7 Workmanship. Workmanship shall be in accordance withMIL-w-13855.

4. QUALITY ASSUW+.NCE PROVISIONS

4.1 Responsibility for inspection. Unless otherwisespecified in the contract or purchase order, the contractor isresponsible for the performance of all inspection requirements(examinations and tests) as specified herein. Except asotherwise specified in the contract or purchase order, thecontractor may use his own or any other faci-lities suitable forthe performance of the inspection requirements spec~fled h=einjunless disapproved by the Government. The Government reserves

the right to perform any of the inspections set forth in thisspecification where such inspections are deemed necessary to

ensure supplies and services conform to prescribed requirements.

4.1.1 Res~onsibilitv for.compliance. All items shall meetall requirements of Sections 3 and 5. The inspection set forthin this specification shall become a part of the contractor’soverall inspection system or quality program. The absence of any

inspection requirements in the specification shall not relievethe contractor of the responsibility of ensuring that allproducts or supplies submitted to the Government for acceptancecomply with all requirements of the contract. Sampling

inspection, as part of manufacturing operations, is an acceptablepractice to ascertain conformance to requirements, however, thisdoes not authorize submission of known defective material, eitherindicated or actual, nor does it cormnit the Government to acceptdefective material.


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4.1.2herein, the

MIL-G-71047 (AR) “-’

General ~rovisions . Unless otherwise specifiedprovisions of MIL-W-63150 apply and form a part

this specifi~ation. Reference shall be made to MIL-S~-109define quality assurance terms used herein. .

4.2 Classification of inspections. The inspectionrequirements specified herein are classified as follows:

a. First article inspection (see 4.3).

b. Quality conformance inspection (see 4.4).

4.3 First article inspection.

ofto

4.3.1 Submission. The contractor shall submit a firstarticle sample as designated by the Contracting Officer forevaluation in accordance with provisions of 4.3.2. The firstarticle sample shall consist of the assemblies, components andtest specimens “listed below in the.quantities indicated.

Name Drawinq $hantity

Machine Gun, Cal .50 12949648 15

4.3.2 Inspections to be nerformed. As determined by theGovernment, Che first article assemblies, components and testspecimens may be subjected co any or all of the examinations andtests specified in Table 11 and be inspected for compliance withany or all requir~ments of the applicable drawings.

4.3.3 Rejection. If any assembly, component or testspecimen fails to comply with any of the applicable requirements,the first article sample shall be rejected. The Governmentreserves the right to Eexminate inspection upon anyassembly, component or test specimen to comply withrequirements.

failure of anany of the

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MIL-G-71047 (AR) ““

TABLE II. Examinations and tests.

(100% Inspection unless otherwise specified.).

TestSample Require- Method/

Defect Characteristic Size ment Paragraph

Critical None defined.

Major

101 Sear engagement 100% 3.2.1 4.5.1102 Firing pin protrusion 100% 3.2.2 4.5.2103 Headspace 100% 3.2.3 4.5.3104 Timing ‘ 100% 3.2.4 4.5.4105 Weight 100% 3.3.1 SMTE106 .Dimension 100% 3.3.2 SMTE107 ‘Firing pin release Note a 3.4.1 4.5.5108 Firing pin indent Note b 3.4.2 4.5.6109 High pressure

resistance 100% 3.4.3 4.5.7110 Functioning 100% 3.4.4 4.5.8111 Belt pull 100% 3.4.5 4.5.9

112 Cyclic rate of fire 100% 3.4.6 4.5.10113 Targeting and

accuracy test 100% 3.4.7 4.5.11llQ Endurance Note c 3.4.8 4.5.12115 Barrel erosion Note c 3.4.8.1 4.5.13116 Interchangeability Note b 3.5 4.5.14117 Packaging 100% 5.1-5.3 4.5.15

Minor

201 Marking 100% 3.6 4.5.16202 Workmanship 100% 3.7 4.5.17

NOTES: a. Ten bolt assemblies per lot. Accept on zero defect.Reject on one defect.

b. Ten machine guns per lot. Accept on zero defect.Reject on one defect.

c. One machine gun per lot. Accept on zero defects.Reject on one defect.


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MIL-G-71047 (AR)

4.4 @alitv conformance inspection.

4.4.1 Inspection lot formation. The term “inspection Iotais defined as a homogeneous collection of units of producG fromwhich a representative sample is drawn or which is inspected 100percent to determine conformance with applicable requirements.lJmiEs of product selected for inspection shall represent only theinspection lot from which they are drawn and shall not beconstrued to represent any prior or subsequent quantitiespresented for inspection. Homogeneity shall be considered toexist provided the inspection lot has been produced by onemanufacturer in one unchanged process, using the same materi~lsand methods, in accordance with the same drawings, sme drawingrevisions, same specifications and same specification revisions.All material submitted for inspection in accordance with thisspecification shall comply with the homogeneity criteriaspecified herein, regardless of the type of inspection procedurewhich is beinq applied to determine conformance withrequirements.

4.4.2 Examinations and tests.

4.4.2.1 Classification of characteristics. Qua1ityconformance examinations and tests are specified in Table 11.The contractor’s quality program or detailed inspection systemshall provide assurance of compliance of all characteristics withthe applicable drawing and specification requirements utilizingas a minimum the conformance criteria specified.

, 4.4.2.2 Failure data. Unless otherwise specified herein,all tests shall be conducted on a complete machine gun. If testrequirements cited herein are not met, acceptance of the machinegun shall be deferred and the contractor shall accomplish, asapplicable, the following actions:

a. Conduct a failure analysis study performing adimensional, physical and visual examination of the compone.cswhich are suspected to be the cause of failure or malfunction.

b. Evaluate and correc~ the applicable productionprocesses and procedures to prevent recurrence of the samedefect(s) in future production.

Examine machine guns, partially assembled machineguns, and ~omponents (including components and subassefi~ies atin-process or final assembly) to insure that ma&erial containing-the same defect is purged from the inventory and not presented tothe Government for acceptance.

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MIL-G”71047 (AR)

d. Submit the results of the failure analysis and thecorrective actions taken to the Government for review andapproval prior to submitting a reconditioned lot or reconditionedsubassembly for retest.

4.4.2.3 Hanqfires and misfires. If hangfires and misfiresoccur during any of the tests, the “machine gun shall be subjectedto the firing pin indent test (see 4.5.6); and-in the.event thatthe firing pin indent is not within the specified l~mlts, themachine gun shall be rejected.

4.4.2.4 Malfunctions . Malfunctions in any test assignableto improper linking of ammunition, improper feeding of ammunitionto the weapon, or defective anununition, links or testingequipment, shall not count against the machine gun being tested.

4.4.3 Inspection eauipment. Unless otherwise specified(see 6.2), responsibility for acquisition, calibration,maintenance and disposition of acceptance inspection and testequipment required by applicable specifications, shall be inaccordance with MIL-I-45607.

4.5 Methods of inspection.

4.5.1 Sear enqaqement. Each machine gun shall be testedfor sear engagement. Manually retract the firing pin of eachmachine gun by moving the cocking lever rearward. The firing pin

shall engage the sear (see 3.2.1) . Failure to ‘eet ‘herequirements shall be cause for rejection of that machine gun.

4.5.2 Firinq Pin protrusion. Each machine gun shall be

tested for firing pin protrusion. With the firing pin in the

fired position, using gage Drawing 6047008, measure the firingpin protrusion (see 3.2.2) of each machine gun. Failure to meet

the requirements shall be cause for rejection of that machinegun.

4.5.3 HeadsPace. Each machine gun shall be tested forheadspace. Using the procedure provided in TM 9-1090-214-23T#and the headspace gage, 12003958 or ~351211/ adjust the headspace

of each machine gun. Failure to meet the requirements of 3.2.3shall be cause for rejection of that machine gun.

4.5.4 Timinq. Each machine gun shall be tested for timing.Using the procedure provided in TM 9-109O-214-23T and timinggage, 12003959, or 5351213 and 5351214, adjust the timing of eachmachine gun. Failure to meet the requirements of 3.2.4 shall because for rejection of that machine gun.

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MXL-G-71047 (AR) “

4 .5.5 Firin~ pin release tes~ina. Ten bolt assembliestaken at random from each 10E of machine guns shall be tesked forfiring pin release (see 3.4.1). Failure to meet the requirementsshall be cause for rejection of the lot of machine guns. .

The firing pin release test shall be performed using anapproved fixture (see Drawing 6511053 or 7270150). Theappropriate load per 3.4.1 shall be applied slowly and uniformlyat the following points until the firing pin is released: Firstto the sear slide on one side; second, with the sear slic:ereversed, to the sear slide on the other side; and third,directly to the sear froxnthe top. The load shall be appliedfive times at each of the three points.

4.5.6 Firina pin indent testina. Ten machine guns fromeach lot shall be tested for firing pin indent (see 3.4.2) .Failure to meet the requirements shall be cause for rejection ofthe lot of machine guns..

The indent, when taken in Government Standard coppercompression cylinders (Drawing 8440920) inserted into a holdingfixture (Drawing 5520627), shall be computed by measuring thedistance from the original surface (before indentation) of thecylinder to the bottom of the impression.

4.5.7 Hiah pressure resistance testina. Each machine gunshall be tested for high pressure resistance (s@e 3.4.3) .Failure to meet the requirements shall be cause for rejection ofthat machine gun.

.Machine guns shall be mounted in a firing fixture with

safety cover conforming to Drawing 8440929 or approved equvalentand tested by firing one high pressure test cartridge. Afterproof firing, the high pressure cartridge case shall be visuallyexamined for bulges, splits, rings, and other defects caused bydefective barrels; the gun shall be examined for cracks#-deformations, or other visible damage; and the barrel assembly,barrel extension assembly, and bolt subassembly’ shall be magneticparticle inspected in accordance with MIL-STD-1945 and theapplicable drawings.

4.5.8 Functioning testinc. Each machine gun shall betested for functioning (see 3.4.4). Failure to meet cherequirements shall be cause for rejection of that machine gun.

The machine guns shall & tested for funCt~Oning as fOllOWS-:

Each machine gun shall be fired 50 rounds right side feed using atest fixture (Drawing 8440929). Each 50 round segmen. shall befired 25 rounds spasmodic and 25 rounds continuous burst.

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MIL-G-71047 (AR)

4.5.9 Belt pull testinq. Each machine gun shall be testedfor belt pull (see 3.4.5) . Machine Guns which fail to meetthese requirements can be retested subject to the provisions ofparagraph 4.4.2.2. They may then be mechanically gymnasti.catedfor a period not longer than ten minutes, and then retested.Failure of the retest to meet the requirements shall be cause forrejection of that machine gun.

The machine gun shall be tested for belt pull using theapplicable pieces of the belt pull test fixture (Drawing8440929). Each machine gun shall be fired a ten round burstright side feed for belt pull test. The ten round metalliclinked belts “shall be loaded with ten rounds of live and tworounds of dummy ammunition. The live afiunition shall feed intothe machine gun first: The turn-buckle part 15 of the fixtureshall be adjusted to feed the rounds horizontally or with notover a 5 degree rise from the pulley to the feedway of theweapon.

4.5.lC Cyclic rate of fire testinq. Each machine gun shallbe tested for cyclic rate of fire (see 3.4.6). This test may beperformed concurrently with 4.5.8. Failurerequirement shall be cause for rejection of

Each machine gun shall be fired, using8440929), 25 rounds continuous fire and therecorded.

to meet thethat machine gun.

test fixture (Drawingcyclic rate of fire

4.5.11 Tarqetinq and accuracy testinq. Each machine gunshall be tested for targeting and accuracy (3.4.7). Failure tomeet the requirements shall be cause for rejection of thatmachine gun.

The machine gun shall be mounted in a firing fixtureconforming to drawing’ 8440929 or an approved equivalent.Boresight Kit, Cal. 50; 11838715, shall be used to si9ht.theweapon on the sighting image of the targeting and accuracydiagram, 12011845, and a 50 round continuous burst fired.

4.5.12 _Endurance testina. One machine gun from each lotshall be tested for endurance (see 3.4.8), after having beenfound to be satisfactory in all previous tests. Failure to meetthe require:’tentsshall be cause for rejection of the lot ofmachine guns.

The machine gun shall be mounted in a firing fiXtUreconforming to Drawing’ 8440929 or an approved equivalent. Thefiring schedule shall be 50 rounds in interrupted bursts followedby 50 rounds in a continuous burst. The barrel shall beaircooled to ambient tempera..ure after each 100 rounds fired.

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MIL-G-71047 (AR) -

The ammunition may be linked in 50 round belts or in 100 roundbel~s with a dummy inert round separating each 50 rounds. Duringthe interrup~ed burst firing, the bolt latch release shall bereleased at least twice to stop the firing and the trigger shallbe released at least three times to stop firing. The averagecyclic rate of fire for 25 rounds shall be measured and recordedduring the firsC 50 round continuous burst of each 1000 rounds.The average muzzle velocity of 10 consecutive rounds shall bedetermined during the first 50 rounds fired, during, 4900-5100round fired and during 9900-10,000 rounds fixed. Ten rounds maybe fired for warm-up before the velocity 5.smeasured.

4.5.12.1 Maintenance. The machine gun shall be cleaned,oiled and inspected after each 1000 rounds and at the close ofeach day’s firing. No component shall be altered or replaced,except those components which are broken or worn to the extentthat they are unserviceable shall be replaced.

4.5.12.2- Records. Complete, accurate records shall be keptfor each endurance test, showing each malfunction and partreplacement including the round number when each occurred.

4.5.12.3 Endurance retest. If the machine gun representingany lot fails to meet the specified requirements in the endurancetest, a retest shall be made subject to provisions of 4.4.2.2.

In case a retest is made, the Government representativeshall select another machine gun for the retest from the lotunder consideration. If a retes~ is not made or the machine gun

.selected fails in the retest, the lot shall be rejected.

4.5.13 Barrel erosion Eestinq. Each endurance tesC barrelshall also be tested concurrently for barrel erosion (see3.4.8.1). Failure to meet the requirements shall be cause forrejection of the lot of machine guns.

4.5.14 Tnterchanaeabilitv testinu.

4.5.14.1 In plant.

4.5.14.1.1 Machine inns. The contractor shall test asample of 10 machine guns, selected by the Government repre-sentative from each inspection lot, for interchangeability (see3.5). Machine guns taken for interchangeability testing shallhave been found satisfactory in all other examinations and tests.Test frequency may be reduced, on approval of the procuring -agency, to not less than one test of 10 machine guns each monthwhen a record of consistently satisfac~ory results has beenestablished. The 10 machine guns shall be inspected for andshall comply with the requirements for firing pin protrusion,

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MIL-G-71047 (AR)

headspace, timing and firing pin release before and afterinterchange of parts using the inspection methods specified in4.5.2, 4.5.3, 4.5.4 and 4.5.5, respectively. In addition, themachine guns shall be tested for functioning, targeting, andaccuracy requirements after interchange of parts using The testmethods specified in 4.5.8 and 4.5.11, respectively. Failure tomeet the interchangeability test shall cause rejection of therepresented lot.

Machine guns shall be tested. for interchangeability bydisassembling and then reassembling parts using the parts andprearranged system specified below. Interchange of parts shallbe accomplished by dividing the parts of each machine gun into 10groups of nonmating parts as shown below and distributing thegroups into 10 different trays until each tray contains parts fora complete machine gun. Groups of parts from the first machinegun shall be taken in order and placed in trays 1 through 10;groups of parts from the second machine gun shall be taken inorder and placed in trays 2 through 10 to 1; groups of parts fromthe third machine gun shall be taken in order and placed in trays3 through 10 to 2; etc. Commercial parts such as screws, springpins, etc., shall’be placed in the same tray as their mating orassociate part. my commercial part rendered unserviceable bydisassembly shall be replaced without penalty to the inter-changeability test. The machine guns shall be reassembled usingonly-those parts which are in the same tray.

GROUPS OF NONMATING PARTS

GROUP I

Bar, TriggerBarrel AssyExtension Assy,

Firing PinExtractor AssyPin, Cocking

LeverSpring, Cover

LatchCam, Lock,

BreechSpring, Switch

62575928448123

60089766008959

7312078

6008931

61475836008493

GROUP II

Bolt SubassemblyRod Assy, Oil Buffer

PistonPin, LockingSpring, Cover

ExtractorPawl, Cover DetentPin Assy, Breech

LockPin Assy, Trigger

Bar

6147463

60.087637312970

60097417313069, .

6008784

7313106

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MXL-G-71047 (AR) ‘-

GROUPS OF NONMATING PARTS (cont~nued)

GROUP 111

Slide, Sear 5351220Switch, Bolt 5504062Pin Assy, BeltFeed Pawl 6008962

Spripg, HelicalCompression 5013516

Plunger, AdjustingScrew 5152839

Stop Assy, Adjust-able, Trigger Bar 7265212

GROUP v.. -. .

Lock, Acceleratorstop 7161300

Spring, HelicalCompression 5009524

Guide Assy. BufferSpring 6008782

Shafe Assy, CoverLatch 7312723


.Pawl Assy, BeltHolding 7313083

Rod Assy, DrivingSpring 5564305

Stop, Rear,Cartridge 5013540

GROUP VII. .

Arm, Belt Feed Pawl 6008914Lock, Back Plate

LaEch 11010453Plate, Buffer 5152869Screw, Adjusting 5152834Switch, Extractor 6147461Stop Assy, Cartridge

Rear RH 5577409

GROUP IV

Lever, CockingSearStop, AcceleratorSpring, Helical

CompressionPlunger, Belt Feed

Lever

GROUP VI

Accelerator, OilBuffer

600971855040677161301

6009832

5013515

5508141Slide Assy, E=lt Feed 6261110Nut, Slotted, Hexagon 5152939Screw, Externally

Relieved Body 7312028Stripper, Link 5013541Plate Assy, Back 12012004

GROUP VIII

Pin Assy, Accelerator 6008790Disk, Buffer, Fiber 5152835Latch, Back Plate 6008949Pin, Locking 7312517Spring, HelicalCompression 7160628-


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MIL-G-71047 (AR)

GROUPS OF NONMATING PARTS (continued)

GROUP IX

Lever, Belt FeedLock, BreechPin, Straight,

HeadedPin, Belt Holding

PawlSpring, Back Plate

Latch LockSpring, Helical

CompressionPin, Firing

GROUP X

5564278 Pawl Assy, Belt Feed 60089617161302 Extension Assy,

Barrel 55040825013581 Nut Slotted, Hexagon 5013556

Pin, Straight,7313329 Headless 5009275

Spring, Helical6243607 Compression 5009356

Pin, Straight, Headed 50092717313068 Screw, Machine,7310080 Flat Csk Head 5153191

4.5.14.,1;2 Concurrent repair parts. The contractor shallsubject at least two parts from each inspection lot of concurrentrepair parts to the interchangeability test. Failure of any partto meet the requirements shall be cause for rejection of therepresented lot of parts subject to reconditioning and furthertest as a reconditioned lot per 4.4.2.2. A sample of double thenumber of parts used in the original test shall be tested fromeach reconditioned lot.

Concurrent repair parts shall be tested for interchange-ability by disassembling two machine guns, previously tested in4.5.14.1.1, as necessav, and then reassembling them using theconcurrent repair parts. No hand refinements of parts will beallowed, and the machine guns shall operate and functionproperly. This test may be performed independently of themachine gun interchangeability test specified in 4.5.14.1.1 andat more frequent intervals using accepted machine guns taken fromcurrent production.

4.5.14.2 InterPlant. When machine guns are manufacturedconcurrently by more than one contractor, each contractor shallforward monthly six machine guns for the’interplant interchange-ability test. The contractor will be informed of the results ofthe test which indicates failure of the machine guns to meetprescribed requirements.

Machine guns to be subjected to the interplant interchange-ability test shall be given preliminary hand functioning toassure proper operation before parts are disassembled. Inaddition, the machine guns shall be inspected for firing pinprotrusion, headspace, timing, firing Pin release, functioningand accuracy before and after interchange of parts using the

18


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.

MIL-G-71047 (AR) ““’

inspection methods specified in 4.5.2, 4.5.3, 4.5.4, 4.5.5, 4.5.8and 4.5.11, respectively. Machine guns shall be interchanged ina manner similar to the detailed plan specified in 4.5.14 exceptthat parts shall be divided into six groups and when dis-.assembling. every other machine gun used shall be one produced bya different manufacturer. Before machine guns are returned tothe contractors, the original parts shall be reassembled to theirrespective machine guns, and the machine guns shall be handfunctioned to assure proper opera~ion.

4.5.15 Inspection of ~ackaqinq. Unless otherwise specified(see 6.2), inspection to determine compliance with preservation,packing and marking requirements of the applicable packagingdocumentation, for the level designated in the contract, shall beas specified in MIL-P-14232.

4.5.16 Markinq. Visually examine each machine gun for allmarking to assure that they are correct and legible (see 3.61.

4.5.17 Workmanship. Visually and manually examine eachmachine gun co determine conformance with the applicablerequirements. Each step in the examination shall include avisual examina&ion for proper cleaning, the presence of thespecified pro~ective coating, and to determine general quality,completeness of manufacture, assembly and workmanship (see 3.7) .

5. PACKAGING

5.1 Pilot pack. A pilot pack shall consist of a complete-machine gun preserved in accordance with the Packaging Data Sheetfor the level of protection specified in the contract (see 6.1),packed Level B and fowarded as specified in 3.1.

5.2 Levels A and B. Preservation, packing and markingshall be in accordance with Special Packaging InstructionPS 12949648 for the level of protection shall be as spec$fi.ed inthe contract (see 6.1).

5.3 Renair parts. Repair parts shall be preserved, packed,and marked in accordance with the Packaging Data Sheet or other “packaging requirements, as specified in the contract (see 6.1).

6. Noms

(This section contains informationnature that may be helpful, but is

of a general or explanatorynot mandatory. )

6.1Armament

Intended use. ThisSubsystem Helicopter

machine gun324149 POD.

19

is for use in the


.,

MIL-G-71047 (AR)

6.2 Acquisition requirements. Acquisition documents must

specify the following:

a.

b.

c.

d.’

e.

f.

9.

h.

i.

j.

k.

1.

Title, number and date of this specification

Issue of DODISS to be cited in the solicitation,and, i.f required, the specific issue of i.ndivi.dualdocuments referenced (see 2.1.1).

Requirements for submission of first articlesample.

List of drawings, specifications and publicationspertinent to the machine gun, showing applicabledates of revision.

Shippin,g instructions for first article’ and PilOtpack (s&e 3.1, 4.3 and 5.1).

When the Government will provide barrel assembliesfor endurance testing (see 3.4.81.

Block of serial numbers for quantity of machineguns or order (s= 3.6)-

Inspection lot size, if other than specified {s=4.4.1).

Quantity, shipping instructions and test proceduresfor machine guns required for interplantinterchangeability test (see 4.4.2.18.2).

Packaging inspection, if different (see 4.4.4)..,,

Selection of Level A or B packaging (see 5.1 and5.2).

Packaging instructions for repair parts (see S.3) .

6.3 Submission of contractor inspection equipment desiqnsfor armroval. Submit copies of designs as required to:Commander, U.S. Am ARDEC, ATTN: SMCAR-QAF-1, PicatinnYArsenal, NJ 07806-5000. This address will be specified on theContract Data Requirements List, DD Form 1423 in the contract.

20


1“

.....

MIL-G-71047

6.4 Drawinqs. Drawings listedfication under Che heading U.S. Army

(AR) -

in Section 2 of this speci-Armament, Research, Develop-

ment and Emzineering Centzr (ARDEC)-may also include drawingsprepared by; and identified as U.S. Am A~mentt Research andDevelopmen& Command (ARRADCOM), Frankford Arsenal, Rock IslandArsenal or ?icatinny Arsenal drawings. Technical data originally

prepazed by these activities is now under cognizance of ARDEC.

6.5

Custodian:Army-m

Subiect term (kev word) listinq.

Belt pull testTargeting and accuracy testEndurance test

Preparing activity:Army-AR

(Project 1005-A758)


STANDARDIZATION DOCUMENT IMPROVEMENT PROPOSAL..

lN=RUGIIWS1. The preparing activity must complete blocks1,2,3,and 8. In block””l, both the document number and revision

MMer should be given.

2. The submitter of this form must complete blocks 4, 5, 6, and 7.

3. The preparing activitymustprovide a reply within 30 daysfrom receipt of the form...

NOTE: Thisform may not be used to requestcopies of documents, nor 10 request waivers, or clarification ofreqtdremen!s on current contracts. Comments submitted on this form do not constitute or ~mpiy authorization to

waive any portion of the referenced document(s) or to amend contractual requ!raments.

1. DOCUMENT FJUMBIW! 2. OOCUMENT C)ATEfYYMb400j

L oocuMENr77nE

5. R-ON FOR RECOMMENDATION

c. Aoomms (bdutfe .7@ Cole)

ItF YOU 00 NOT RECEIVZ A HE~Y WITHIN & DAYS. CONTACT:

00fwwO Gmtfty and S!an4~rdzal10n Otflco$202 I.oosburo Pike. Sul!a 1=, Falls Church. VA 22041-_ToloPhom (702) 7S6-2340 AUTOVON =9-Z3$0

1- $ .) ,>..-

)D ~oflll 1426, OCT 89 Fmiou edifiom arc obsokfe. Isa/z
