HS-JXNN-C11-0008_Rev_1_MK_255_MOD_1_Reduced_Ricochet_Limited_Penetration.pdf

HS/JXNN/C11/0008 Rev. 1

HYBRID SPECIFICATION

CARTRIDGE, CALIBER 5.56MM,

REDUCED RICOCHET LIMITED PENETRATION (RRLP),

MK 255 MOD 1

1. SCOPE

This specification establishes the requirements for the Cartridge, 5.56mm Reduced Ricochet Limited Penetration (RRLP), MK 255 MOD 1. The ammunition shall be referred to hereafter as the MK 255 MOD 1 cartridge.

2. APPLICABLE DOCUMENTS

2.1 Government Documents. The following documents of the latest issues form a part of this document to the extent specified herein. In the event of a conflict between this specification and other documents referenced herein, requirements of this specification shall apply.

SPECIFICATIONS

MILITARY

MIL-L-63460.........Lubricant, Cleaner and Preservative

STANDARDS

MILITARY

MIL STD 636.........Visual Inspection Standards for

Small Arms Ammunition through Caliber .50

MIL-STD-644.........Visual Inspection Standards and

Inspection Procedures for Inspection of Packaging Packing and Marking of Small Arms Ammunition

MIL-STD-1168........Ammunition Lot Numbering

DEPARTMENT OF DEFENSE

DOD-STD-2101........Classification of Characteristics

UNITED STATES

FED-STD-595.........Colors Used in Government

Procurement

DRAWINGS

NSWC, CRANE

12255-408JXN00025...Cartridge, 5.56mm RRLP, MK 255 MOD 1

U.S. ARMY ARMAMENT RESEARCH AND DEVELOPMENT COMMAND

19200-7643674.......Classification of Cartridge Case

Defects

19200-9378276.......Case

19200-10534279......Primer, Number 41

19200-8649409.......Barrel, Test, Accuracy, 5.56mm

PUBLICATIONS

U.S. ARMY

SCATP-5.56MM

(Heavy Bullet)......Small Caliber Ammunition Test Procedures, 5.56mm (Heavy Bullet) Cartridges

(Unless otherwise indicated, copies of the above specifications, standards, and publications are available from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia PA 19111-5094.)

2.2 Non-Government Publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents that are DOD adopted are those listed in the issue of the DODISS cited in the solicitation. Unless otherwise specified, the issues of the documents not listed in the DODISS are the issues of the documents cited in the solicitation.

AMERICAN NATIONAL STANDARDS

ANSI/ASQC-A8402-1994.....Quality Management and Quality Assurance - Vocabulary

ANSI/ASQC Z1.4-2003......Sampling Procedures and Tables for

Inspection by Attribute

(Application for copies should be addressed to the American National Standards Institute, Headquarters, 11 West 42nd Street, 13th Floor, New York NY 10036. ANSI may also be contacted via their web site at www.ansi.org.)

2.3 Order of Precedence. In the event of a conflict between the contract, the text of this document and the references cited herein, the contract takes precedence, followed by the text of this document, then the documents referenced herein. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

3. REQUIREMENTS

3.1 Item Description. The MK 255 MOD 1 cartridge shall comply with all requirements specified on drawing 12255-408JXN00025, all associated drawings and with all requirements specified in applicable specifications and standards. The MK 255 MOD 1 cartridge contains a projectile that is designed to fragment upon impact on hard surface. The cartridge is designed to function in rifles and carbines chambered for this caliber without modifications.

3.2 Classification of Characteristics. DOD-STD-2101 shall be

used for classification of characteristics. Where critical or major characteristic requirements are listed in this specification, they are annotated by a "C" or "M" and sequential reference number starting with "1" for critical and "101" for major. The letter and number are contained in parentheses. The main statement of the requirement is then surrounded by brackets, "[ ]". Minor characteristic requirements contain no annotation.

3.2.1 Critical Characteristic. One that analysis indicates is likely, if defective, to create or increase a hazard to human safety or to result in failure of a weapon system or major system to perform a required mission.

3.2.2 Major Characteristic. One that analysis indicates is not critical but is likely, if defective, to result in failure of an end item to perform a required mission.

3.2.3 Minor Characteristic. One that analysis indicates is

significant to product quality but is not likely, if defective, to impair the mission performance of the item.

3.3 Components. All components, packaging, and shipping

materials shall be of new manufacture and shall look to be clean and in new condition.

3.3.1 Projectile. (C1) [The projectile shall not contain lead and other toxic material]. The core shall be frangible and encased in a full metal jacket having a knurled cannelure and a durable gray color-code (reference FED-STD-595, color number 26493) either on the tip or over the entire projectile, for identification purposes. Unless the entire projectile is colored, the coloring shall extend from the tip toward the base for a distance of at least 0.25 inches. The projectile shall weigh 62 grains ± 1 grain. The projectile diameter along the cylindrical bore bearing surface shall be 0.2245 inch maximum,

0.2240 inch minimum.

3.3.2 Cartridge Case. The cartridge case shall be a military

5.56mm copper alloy case manufactured in accordance with Army drawing 19200-9378276. Upon assembly, the case mouth shall be securely crimped into the projectile cannelure, and a visible sealant compound shall be applied to the crimped area to protect against water intrusion. (C1) [A vent hole shall be present in the primer pocket of the cartridge case.]

3.3.2.1 Headstamp. The cartridge case headstamp marking shall consist of the identification code of the manufacturer and the last two digits of the year of manufacture.

3.3.2.2 Residual Stress. The cartridge case shall not split

when subjected to a 1% mercurous nitrate solution for 15 minutes.

3.3.3 Primer. The primer shall be a number 41 primer

manufactured in accordance with Army drawing 19200-10534279 for M855 Ball ammunition and shall be crimped in place. The primer to primer pocket joint shall be sealed against water intrusion using a visible sealing compound.

3.3.3.1 Primed Case Sensitivity. The average critical height

(H) plus three standard deviations (3 sigma) shall be 12.0 inches maximum and the average critical height minus three standard deviations (3 sigma) shall be 3.0 inches minimum.

3.3.4 Propellant. The propellant shall be Western C1700

propellant with flash-reduction additives. The charge weight shall be selected by vendor to meet the requirements of this specification. The propellant must be approved by the Department of Transportation as a Class C explosive.

3.4 Complete Cartridge.

3.4.1 Primer Seating Depth. (M101) The primer shall be seated in the cartridge case to a depth of 0.000 to 0.008 inch below the face of the cartridge case head.

3.4.2 Overall Length. (M102) The overall length of the

assembled cartridge shall be 2.205 inches minimum to 2.235 inches maximum.

3.4.3 Bullet Extraction Force. The force required to extract

the projectile from the cartridge case shall be 45 pounds minimum.

3.4.4 Waterproofness. (M103) After being submersed in +70°F

fresh water at a pressure of 28 to 31 psig for 60 to 65 minutes, all cartridges shall fire, function the weapon, and have a corrected muzzle velocity of 2,300 fps minimum.

3.5 Cartridge Ballistics Performance.

3.5.1 Velocity. (M104) The corrected average muzzle velocity of cartridges conditioned at any temperature test point of -25°F, +70°F, or +125°F, shall be 2,650 feet per second (fps) minimum, measured 78 feet from the muzzle.

3.5.2 Chamber Pressure.

3.5.2.1 (M105) The corrected average chamber pressure of cartridges conditioned at +70°±2°F shall not exceed 58,700 pounds per square inch (psi). Neither the chamber pressure of an individual sample test cartridge nor the average chamber pressure plus three standard deviations shall exceed 64,700 psi.

3.5.2.2 (M106) The corrected average chamber pressure of cartridges conditioned at 125°±2°F and -25°±2°F shall not vary from the average chamber pressure of the sample test cartridges conditioned at 70 2F by more than 7,000 psi. The average chamber pressures of the sample cartridges of the same lot conditioned at 125 2F shall not exceed 63,700 psi. Any decrease in chamber pressure is acceptable.

3.5.3 Gas Port Pressure.

3.5.3.1 (M107) The corrected average port pressure minus three standard deviations shall be 15,300 psi minimum for sample cartridge conditioned to +70°±2°F.

3.5.3.2 (M108) The corrected average port pressure of cartridge conditioned at 125°±2°F and -25°±2°F shall not vary from the average chamber pressure of the sample test cartridges conditioned at 70°±2°F by more than 2,000 psi, and shall not be less than 14,600 psi.

3.5.4 Accuracy (100 and 300 yards). (M108) The extreme spread of any individual 5-shot group shall not exceed 2.0 inches at 100 yards or 6.0 inches at 300 yards.

3.5.5 Ballistics Matching (100 and 300 yards). The center of

impact of the test cartridges shall be within 1.5 inches of the center of impact of M855 Ball rounds fired at 100 yards, and within 4.5 inches at 300 yards.

3.5.6 Reverse Splatter. (M109) When fired onto a 1/4-inch thick AR500 hardened steel plate at a distance of 15 feet, no particles shall ricochet backwards and penetrate a witness panel of standard B-flute single-wall corrugated cardboard positioned directly behind the weapon muzzle.

3.5.7 Function and Casualty. The cartridges shall meet the

function and casualty accept/reject requirements of Table I when fired from the weapons specified in Appendix B. Misfires shall be considered separately in accordance with Table I.

Table I: Cartridge Defect Classification and Accept/Reject Criteria

FIRST SAMPLE CUMULATIVE

Characteristic 1/ Classification ACCEPT/REJECT ACCEPTANCE 2/

1. Misfire 3/ (M110) No vent hole or obstruction in vent area 4/ 0 1 -

Other 0 1 1

2. Hangfire 4/ (C2) 0 1 -

3. Bullet remaining in bore 4/ (C3) 0 1 -

4. Primer leaks

a. Perforation in firing pin indent in primer cup (M111) 1 3 2

b. Escape of gas through primer cup (excluding 4.a. above) (M112) 1 3 2

c. Escape of gas around primer cup

(1) 50% of periphery or more (minor) 3 7 9

(2) Less than 50% of periphery (minor) 5 9 13

d. Blown primer - Primer separates from case head and primer pocket is grossly distorted. 4/ (C4) 0 1 -

e. Dropped primer - Primer falls out of pocket upon retraction of bolt (M113) 0 2 1

f. Loose primer - Primer remains in pocket but is loose (M114) 0 2 2

5. Case casualties

a. Longitudinal split 5/

(1) Neck and shoulder (I or S) (minor) 5 9 13

(2) Body (J) (minor) 3 7 9

(3) Body (K) (M115) 0 2 1

(4) To head (L) (M116) 0 2 1

(5) Through head (M) (M117) 0 2 1

b. Circumferential rupture 5/

(1) Partial, shoulder or body (J and S) (M118) 1 3 2

(2) Partial, body (K) 4/ (C5) 0 1 -

(3) Partial, head (L) 4/ (C6) 0 1 -

(4) Complete 4/ (C7) 0 1 -

6. Weapon Stoppage (M118) 0 1 1

7. Bullet Integrity 6/ (M119) 1 3 2

Notes:

1/ For definition of characteristics see 6.1.

2/ The acceptance and retest numbers of Table I shall be as follows:

a. The acceptance and retest numbers shall be applied to each weapon type (all temperatures combined) individually.

Table II: Cartridge Defect Classification and Accept/Reject Criteria (con’t)

b. All function and casualty defects observed in other ballistics tests shall be included in the defect counts of weapon type that was used in the test.

c. If function and casualty defects occurred in a test barrel, then the defects shall be included in the defect counts for each weapon type.

d. When either weapon test is failed and a retest is permitted by

Table I, retest is performed using a double sample size in the failed weapon type only. The test shall be conducted in accordance with Appendix B. The cumulative (1st and 2nd test combined) defect count shall be evaluated against the cumulative acceptance criteria of Table I for the failed weapon type only.

3/ Each cartridge that misfires shall be disassembled and examined to determine the cause of the misfire.

a. The lot shall be rejected if the cartridge does not meet the critical requirements of paragraph 3.3.2 (presence of primer pocket vent hole) or paragraph 3.3.4 (presence of propellant charge).

b. If the misfire is attributed to the test weapon, then the weapon shall be repaired or replaced and another cartridge fired in place of the misfire.

4/ No second sample permitted. Lot shall be rejected.

5/ For location of defects indicated by letters in parentheses, see Drawing 19200-7643674.

6/ Retest is permitted using a double sample size in the failed weapon type, single mode firing only.

3.5.8 Gelatin Penetration. (M120) When fired from an

unsuppressed M4A1 rifle into a ballistic gelatin block (10% gelatin powder by weight) at a distance of 15 feet, the projectile should form a football-shaped temporary wound cavity (TC) that starts within the first two inches after impacting the block. The overall length of the TC should be at least six inches and the TC largest diameter should be at least three inches. The projectile should fragment into a minimum of eight pieces that weigh 1.0 grain or more each. At least three pieces should be less than seven inches deep in the block, at least three should be greater than seven inches deep, and at least one should penetrate 13 inches or deeper.

3.5.9 Steel Plate Penetration. (M121) When fired from an

unsuppressed M4A1 rifle onto a 1/4-inch thick AR500 hardened steel plate (3/4 inch maximum diameter impact area) at a distance of 15 feet, 25 rounds must impact without penetrating the plate.

3.5.10 Bullet Integrity. The projectile shall not break either in its passage through the barrel or in flight when fired from the respective weapons at temperatures ranging from -25°F to 125°F.

3.6 Workmanship.

3.6.1 Defects. Metallic components and the completed cartridge shall be free from folds, wrinkles, deep draw scratches, scaly metal, dents, burrs and other defects.

3.6.2 Foreign Material. All components and the completed

cartridge shall be free of foreign material including, but not limited to, corrosion, stains, dirt, oil, grease, smears of lacquer and metal chips.

3.6.3 Visual Standards. The cartridge and components shall meet the visual standards requirements of MIL-STD-636 for (NATO caliber 7.62mm Section). Classification of individual visual and workmanship characteristics shall be as defined by MIL-STD-636.

3.6.4 Mixed Ammunition Types. For mixed ammunition types, the occurrence of a high pressure test, dummy or blank cartridge shall be classed as a critical defect. Occurrence of any other type shall be classed as a major defect.

3.7 Lot Formation. Each inspection lot of cartridges shall be submitted in accordance with ANSI/ASQC Z1.4-2003. Lot size shall be 250,000 cartridges minimum and 1,500,000 cartridges maximum.

Each lot shall be assigned a lot number in accordance with MIL-STD-1168. Only one type and weight of propellant shall be used in a lot of cartridges. Each lot shall contain no more than one lot of primers and one lot of propellant. Individual components manufactured by more than one contractor shall not be used in a lot of cartridges.

3.8 Primer Lots. The size of any lot of primers used in the

cartridges shall be 250,000 units minimum and 2,000,000 units maximum. A primer lot shall consist of a specific product, made on consecutive work shifts, with no break in the production of that specific product.

4. VERIFICATION.

4.1 Responsibility for Inspection. Unless otherwise specified herein, in the contract or in the purchase order, the supplier is responsible for the performance of all inspection and test requirements as specified herein. Except as otherwise specified, the supplier may utilize his own facilities or any commercial facility acceptable to the Government. The Government reserves the right to perform any of the inspections and tests set forth in this specification where such inspections and tests are deemed necessary to ensure that supplies and services conform to prescribed requirements. Unless otherwise specified herein, in the contract or in the purchase order, all test and inspection equipment (including test barrels and test weapons) shall be supplied and maintained by the contractor.

4.2 Responsibility for Compliance. All items shall meet all

requirements of sections 3 and 5. The inspections set forth in this specification shall become a part of the contractor's overall inspection system or quality program. The absence of any inspection requirements in the specification shall not relieve the contractor of the responsibility of ensuring that all products or supplies submitted to the Government for acceptance comply with all requirements of the contract. Sampling inspection, as part of manufacturing operations, is an acceptable practice to ascertain conformance to requirements; however, this does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to accept defective material.

4.3 Quality Assurance Terms and Definitions. Reference shall be made to ANSI/ASQC A8402 1994 for definitions of quality assurance terms.

4.4 Non-Destructive Inspection Provisions. Unless otherwise

specified herein, the contract or purchase order, General Inspection Level II and Single Sampling Plans for Normal Inspection that are detailed in Table I and Table II of ANSI/ASQC Z1.4-2003 shall be used as the sampling plans and acceptance criteria for nondestructive acceptance inspection of major and minor defects. Inspection shall be by characteristic. Unless otherwise specified the Acceptance Quality Level (AQL) shall be .15 for the inspection of major defects and the AQL shall be .65 for the inspection of minor defects. Unless otherwise specified, 100% inspection shall be used for all non-destructive inspection of critical characteristics. The acceptance criteria shall be to accept on zero defects and reject on one or more defects for the inspection of critical characteristics. Unless otherwise specified, each lot of components and each lot of cartridges shall be inspected in accordance with Paragraph 4.4.1 through Paragraph 4.4.5 as applicable.

4.4.1 Workmanship. Cartridges and components shall be visually inspected to determine compliance with the requirements of Paragraph 3.6.

4.4.2 Dimensional and Weight Requirements. All dimensional and weight requirements in section 3 shall be verified by contractor gages or by standard measuring instruments.

4.4.3 Vent Hole and Propellant. For each cartridge, the

presence of a primer pocket vent hole (Paragraph 3.3.2) and propellant charge (Paragraph 3.3.4) shall be verified by visual inspection or automated equipment prior to projectile insertion.

4.4.4 Packaging, Palletizing, Packing, and Marking. During or immediately prior to the packaging operation, 100% examination of the cartridges shall be performed to ascertain that the cartridge type conforms to the requirements of Paragraph 3.6.4. All non-conforming cartridges shall be rejected. Inspection of packaging, packing, palletizing and marking shall be in accordance with MIL-STD-644 and section 5 of this specification.

4.4.5 Certifications. The contractor shall maintain

certificates and test results showing compliance with all material and lot formation requirements of section 3.

Certifications and test results shall be made available upon request for each production lot.

4.5 Testing Provisions. Unless otherwise specified, each lot of components and each lot of cartridges shall be tested in accordance with Paragraph 4.5.1, Paragraph 4.5.2, related subparagraphs, and Table II as applicable. Unless otherwise specified, all testing shall be conducted with samples conditioned at 70°±5°F for a minimum of two hours. Cartridges shall be randomly selected in such a manner that the sample is representative of the lot. The cartridges shall be thoroughly mixed before being divided into sample groups for each test. If an equipment/weapon failure occurs which prevents the obtaining of a reliable test result, then the equipment/weapon shall be replaced or repaired; the individual test cartridge result shall be disregarded and another sample cartridge shall be fired for record. If the equipment/weapon failure prevented the obtaining of reliable results for the entire test series, then the entire test result shall be disregarded and a complete sample shall be fired for record. If a firing defect occurs which is not attributable to the test conditions, and which prevents obtaining a reliable result for the test, an additional cartridge shall be fired in its place; the test shall not be penalized, but the defect shall be counted in the cumulative ballistics sample for Table I.

Table III: MK 255 MOD 1 Test Matrix

Tests

Quantity for Each Temperature Range

Paragraph References

-27°F to

-23°F

68°F to 73°F

123°F to

127°F

Requirement

Verification

COMPONENT / COMPLETE

CTG.

1. Residual Stress(1) 50 3.3.2.2 4.5.1.1

2. Primed Case Sensitivity

See 4.5.1.2 3.3.3.1 4.5.1.2

3. Bullet Extraction Force(1)

25 3.4.3 4.5.1.3

4. Waterproofness 20 3.4.4 4.5.1.4

BALLISTICS TESTS(1)

5. Velocity / Chamber Pressure / Port Pressure(2)

20 20 20 3.5.1/3.5.2/

3.5.3 4.5.2.1

6. Accuracy 50 3.5.4 4.5.2.2

7. Ballistics Matching 120 3.5.5 4.5.2.3

8. Reverse Splatter 25 3.5.6 4.5.2.4

9. Function and Casualty(3)

540 540 540 3.5.7 4.5.2.5

10. Penetration-Gelatin 4 3.5.8 4.5.2.6

11. Penetration-Steel Plate

25 3.5.9 4.5.2.7

12. Bullet Integrity(4) 3.5.10 4.5.2.8

(1) Failure of the cartridges to comply with the applicable requirement shall be cause for rejection of the lot, subject to testing of a second sample consisting of double the quantity of cartridges used in the first test.

Failure of the cartridges in the second sample to comply with the applicable requirement shall be cause for rejection of the lot. All ballistics tests allow double-sampling retests.

(2) Unless otherwise substantiated that the applicable chamber pressure requirements are met, chamber pressure testing shall be completed and the applicable requirements shall be met prior to conducting any other ballistics tests. Acceptable methods of substantiating that the chamber pressure requirements have been met are in-process chamber pressure checks, or propellant checks, or propellant acceptance tests. These acceptable methods do not eliminate the requirement to perform chamber pressure testing as part of the lot acceptance testing. The contractor shall submit substantiating documentation to and receive approval from the Contracting Officer for each lot that will not be subjected to chamber pressure testing prior to other ballistics tests.

(3) A retest is permitted using a double sample size in the failed weapon type only. Failure of the cartridges in the second sample to comply with the applicable requirement shall be cause for rejection of the lot.

(4) The bullet integrity shall be performed concurrently with Function and Casualty test.

The results of all ballistics tests, including examination of misfired cartridges and fired cartridge cases and primers, shall be used to determine compliance with the requirements of Table I. The occurrence of any critical defects attributable to the cartridges (including firings of warm and foul cartridges from the test lot) shall result in rejection of the lot and no further testing shall be conducted.

4.5.1 Subassembly / Cartridge Tests.

4.5.1.1 Residual Stress. A total of fifty cartridges shall

be used for the residual stress test in accordance with SCATP-5.56mm (Heavy Bullet). The lot shall be rejected if the requirements of Paragraph 3.3.2.2 are not met.

4.5.1.2 Primed Case Sensitivity. The complete sensitivity

rundown test shall be conducted in accordance with SCATP- 5.56mm (Heavy Bullet) using empty primed cases. The test shall be conducted on each lot of primers with fifty (50) primed cases being tested at each one inch increment of height between 0 percent and 100 percent firing. The lot shall be rejected if the requirements of Paragraph 3.3.3.1 are not met.

4.5.1.3 Bullet Extraction Force. A total of 25 cartridges

shall be used for the bullet extraction test in accordance with SCATP-5.56mm (Heavy Bullet). The lot shall be rejected if the requirements of Paragraph 3.4.3 are not met.

4.5.1.4 Waterproofness. Twenty cartridges shall be

submersed in +70°F fresh water at a pressure of 28 to 31 psig for 60 to 65 minutes. They shall then be removed, dried (wiped down), and function fired in an unsuppressed M4A1 rifle. Muzzle velocity shall be recorded at a distance of 78 feet. The lot shall be rejected if the requirements of Paragraph 3.4.4 are not met.

4.5.2 Cartridge Ballistics Tests. The contractor shall

obtain the 5.56mm NATO reference cartridges for calibration of acceptance test equipment, for verification of calibration, and for applying correction factors to test results during Lot Acceptance testing. Also, the contractor shall be responsible for furnishing secondary reference cartridges needed for in-process and in-house testing.

Specified barrel length of test weapons shall be determined by measuring from the breech face of the test weapon to the end of the muzzle.

4.5.2.1 Velocity, Chamber Pressure, and Gas Port Pressure.

The test shall be conducted in accordance with SCATP-5.56mm (Heavy Bullet). The lot shall be rejected if the requirements of Paragraphs 3.5.1, 3.5.2, and 3.5.3 are not met.

4.5.2.2 Accuracy at 100 and 300 Yards. Accuracy testing

shall be conducted in accordance with Appendix A. The lot shall be rejected if the requirements of Paragraph 3.5.4 are not met.

4.5.2.3 Ballistics Matching at 100 and 300 Yards.

Ballistics matching shall be conducted in accordance with SCATP-5.56mm (Heavy Bullet). Thirty rounds each of test cartridges and M855 Ball ammunition shall be temperature conditioned at +70°F and fired from one test barrel onto the target at 100 and 300 yards (60 rounds each total). The process shall be repeated for a second test barrel. The lot of test cartridges shall be rejected if the requirements of Paragraph 3.5.5 are not met.

4.5.2.4 Reverse Splatter. Cartridges shall be tested for

reverse splatter during the steel plate penetration test. A witness panel of standard B-flute single-wall corrugated cardboard (8 ft. X 8 ft.) shall be positioned directly behind the weapon muzzle. The center of the cardboard shall be slit to allow the muzzle to protrude. The lot shall be rejected if the requirements of Paragraph 3.5.6 are not met.

4.5.2.5 Function and Casualty. The test shall be conducted

in accordance with Appendix B. A sheet of 48" x 48" witness paper shall be placed 4 feet to 10 feet from the muzzle of the test weapons to check occurrence of the projectile breakage during the single mode firing. The lot shall be rejected if the requirements of Paragraph 3.5.7 are not met.

4.5.2.6 Gelatin Penetration. The gelatin block penetration

test shall be conducted in accordance with Appendix C. The lot shall be rejected if the requirements of Paragraph 3.5.8 are not met.

4.5.2.7 Steel Plate Penetration. The 1/4-inch AR500 armor

plate penetration test shall be conducted in accordance with Appendix C. The lot shall be rejected if the requirements of Paragraph 3.5.9 are not met.

4.5.2.8 Bullet Integrity. The bullet integrity shall be

performed concurrently with Function and Casualty test during the single mode firing. The lot shall be rejected if the requirements of Paragraph 3.5.10 are not met.

5. Packaging.

5.1 Requirements. For acquisition purposes, the packaging

requirements shall be specified in the contract or delivery order. When actual packaging of material is performed by DoD personnel, these personnel need to contact the responsible packaging activity to ascertain requisite packaging requirements. Packaging requirements are maintained by the Inventory Control Point's packaging activity within the Military Department or Defense Agency, or within the Military Department's System Command.

Packaging data retrieval is available from the managing Military Department's or Defense Agency's automated packaging files, CD-ROM products, or by contacting the responsible packaging activity.

6. Notes.

6.1 Definitions.

6.1.1 Misfire: Failure of a cartridge to fire after the

initiating impulse has been applied to the primer, normally due to either the primer failing to fire after being struck by the firing pin or the propellant failing to ignite after the primer fires.

6.1.2 Hangfire: Any perceptible delay (one second or more)

in the functioning of a cartridge after the initiating impulse has been applied to the primer.

6.1.3 Blown Primer. A primer that falls out when the

cartridge case is ejected and both the head of the case and the primer pocket are enlarged and deformed.

6.1.4 Longitudinal Split. A longitudinal separation of the

metal in the cartridge case wall produced by firing.

6.1.5 Circumferential Rupture. A circumferential

separation of the cartridge case wall produced by firing. A partial rupture is one that extends less than 360 degrees around the case. A complete rupture is one that extends entirely around the case, separating the case into two parts.

6.1.6 Premature Cartridge Function. When the cartridge

functions prior to intentional initiation of the firing mechanism of the weapon. Such failures usually occur during cycling of the weapon mechanism and prior to complete locking of the weapon's bolt.

6.1.7 Loose Primer. Independent movement of the primer in

the cartridge case primer pocket or the primer falls out of the cartridge case primer pocket.

A-1

APPENDIX A

ACCURACY TEST PROCEDURE

A.1 Scope. The accuracy test shall be performed to determine the uniformity and dispersion of the bullets at a specified distance from the test barrel.

A.2 Equipment.

A.2.1. Test Barrels. The test barrels shall be two 20-inch 5.56mm NATO accuracy barrels (Drawing No. 19200-8649409).

A.2.2 Mount. The barrel shall be supported during testing by mounting in suitable fixture as required to permit manual operation of the barrel. The test fixture shall be constructed and mounted so as to prevent fixture movement during testing. It is very important that the barrel maintains its original position from shot to shot.

A.2.3 Targets. All test targets shall be rigidly mounted at the specified test range from the muzzle of the test barrel.

A.2.4 Range. The firing range shall be arranged such that the required horizontal distance from the muzzle of the test barrel to the face of the test target is maintained to within ± 1 yard.

A.3 Test Procedure.

A.3.1 Cartridge Examination. If visual defects are found in the test cartridges prior to testing, the defective cartridge(s) shall be replaced.

A.3.2 Cartridge Conditioning. The required number of test cartridges shall be permitted to come to a temperature of 60 to 80F prior to being placed in the controlled temperature room or container. The cartridges shall be placed in a controlled temperature room or container in such a manner that all the cartridges are subjected to a uniform temperature for a minimum of two hours prior to firing. The room or container shall be maintained at 70 2 F and be of sufficient capacity to allow free circulation of air.

A.3.3 Barrel Preparation. The chamber and the bore of the test barrel shall be thoroughly cleaned and wiped dry prior to firing.

A.3.4 Firing.

A.3.4.1 A minimum of three unrecorded cartridges of the type of ammunition under test shall be fired to assure that

A-2 the test barrel is correctly sighted on the target, to warm and foul the barrel, and to settle the barrel in the test fixture.

A.3.4.2 After the warming and fouling cartridges have been fired, the target shall be changed so as to present a fresh surface for the succeeding rounds.

A.3.4.3 All cartridges shall be singly loaded into the chamber of the test barrel. The required number of cartridges are removed from the controlled-temperature room or container and placed at a point convenient to the technician, provided the temperature of the firing room is 70 2F. Otherwise the cartridges shall be placed in an insulated box (five cartridges at a time) which has been conditioned at 70 2F, and the box placed at a point convenient to the technician. The cartridges are then removed singly from the insulated box immediately before firing. If an insulated box is not available, then the cartridges shall be removed singly from the controlled-temperature room or container immediately before firing.

A.3.4.4 A 5-shot group shall be fired from one test barrel for record. The target shall be changed and another 5-shot group shall be fired. A total of five 5-shot groups shall be fired, with the target being changed after each 5-shot group.

A.3.4.5 The temperature of the test barrel should be controlled so that the exposed metal surface of the barrel does not become too hot to grasp with the bare hands (approximately 140 F). If the barrel becomes too hot to use, it shall be cooled to ambient temperature before the test is continued. After the barrel has cooled to ambient temperature, two warming (fouling) shot shall be fired prior to continuation of the test.

A.3.4.6 The second test barrel shall then be placed in the test fixture and the cartridges shall be tested using the procedures of A.3.4.1 through A.3.4.5 above.

A.3.4.7 Each target shall be measured to determine the maximum extreme spread of each 5-shot group. This shall be accomplished by measuring the center-to-center distance between the two bullet holes which are farthest apart.

Measurements shall be accurate within plus or minus 0.1 inch and results shall be recorded to the nearest one-tenth of an inch.

A.3.4.8 Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.

A-3

A.4 Examinations. All fired cartridge cases and primers shall be visually examined to determine compliance with the applicable requirements of Table I in the specification. In the event that fired case or primer defects are encountered, or if a misfire occurs, then the test barrel shall be examined to determine if the defect is attributable to the barrel. If the barrel is at fault, then the test shall be disregarded and the barrel shall be repaired or replaced prior to performing a retest. If the defect cannot be attributed to the barrel, then the defect shall be attributed to the cartridges. Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.

B-1

APPENDIX B

FUNCTION AND CASUALTY TEST PROCEDURE

B.1 Scope. The purpose of the function and casualty test is to determine if the ammunition will perform satisfactorily in the weapons for which it has been designed.

B.2 Equipment.

B.2.1 Test Weapons. Test weapons shall be two each M4A1, MK 18, and MK 16 rifles, all unsuppressed. No alterations to the test weapons, beyond the requirements and specifications of the original manufacturer or supplier, shall be permitted.

B.3 Test Procedure.

B.3.1 Cartridge Examination. If visual defects are found in the test cartridges prior to testing, the defective cartridge(s) shall be replaced.

B.3.2 Cartridge Conditioning. Test samples shall be temperature conditioned in loaded magazines at the specified temperatures for two hours minimum and shall be fired within two minutes after removal from the controlled temperature conditioning chamber.

B.3.3 Weapon Preparation. Test weapons and magazines shall be thoroughly cleaned prior to the beginning of testing, but shall not be cleaned again until testing at all temperature ranges has been completed. The test weapons shall be lubricated using Cleaner, Lubricant and Preservative (CLP, MIL-L-63460). The magazine parts shall be wiped with a cloth that was sprayed with CLP prior to assembly. All test magazines shall be serialized so as to maintain identity throughout all testing. The weapons shall be maintained at room temperature (55 F minimum) for a minimum of two hours prior to the start of testing. Ammunition test sequence shall be cold temperature condition first, then hot, then ambient for each test weapon.

B.3.4 Firing.

B.3.4.1 Table B1 shows the number of rounds to be fired at each temperature range.

B-2

Table B1: Function and Casualty Test Matrix

Temperature Range (F) -27 68 123 to to to Weapon Mode -23 72 127 M4A1 #1 Single 60 60 60 M4A1 #1 Burst 30 30 30 M4A1 #2 Single 60 60 60 M4A1 #2 Burst 30 30 30 MK 18 #1 Single 60 60 60 MK 18 #1 Burst 30 30 30 MK 18 #2 Single 60 60 60 MK 18 #2 Burst 30 30 30 MK 16 #1 Single 60 60 60 MK 16 #1 Burst 30 30 30 MK 16 #2 Single 60 60 60 MK 16 #2 Burst 30 30 30

B.3.4.2 Cartridges to be fired shall be loaded into 30-round magazines.

B.3.4.3 In the event of a weapon stoppage during the test, the test weapon shall be examined to determine if the stoppage is attributable to the weapon. If the weapon is at fault, then the test shall be disregarded and the weapon shall be repaired or replaced prior to performing a retest.

If the stoppage cannot be attributed to the weapon, then the defect shall be attributed to the cartridges. In addition to weapon stoppages during firing, the following shall also be considered as weapon stoppages:

a. Failure of the last cartridge case to eject from the weapon during any sequence of fire.

b. Failure of the bolt to lock open in the rearward position after firing the last cartridge in each magazine.

c. Failure of the manually chambered cartridge to fully chamber in the barrel of the weapon.

d. Failure of any cartridge to completely chamber, fire and completely eject due to residue build-up in the weapon mechanism from previous firings shall be a stoppage that is attributed to the cartridge.

B.3.4.4 Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.

B.3.5 Examinations. All fired cartridge cases and primers shall be visually examined to determine compliance with the applicable requirements of Table I in the specification. In the event that fired case or primer defects are encountered, or if a misfire occurs, then the test weapon shall be

B-3 examined to determine if the defect is attributable to the weapon. If the weapon is at fault, then the test shall be disregarded and the weapon shall be repaired or replaced prior to performing a retest. If the defect cannot be attributed to the weapon, then the defect shall be attributed to the cartridges. Misfired cartridges shall be disassembled to determine the cause of the misfire.

C-1

APPENDIX C

PENETRATION TEST PROCEDURE

C.1 Scope. The penetration test shall be performed to determine projectile performance against ballistic gelatin and steel plate of known characteristics.

C.2 Equipment.

C.2.1 Test Weapon. The test weapon shall be one unsuppressed M4A1. No alterations to the test weapon, beyond the requirements and specifications of the original manufacturer or supplier, shall be permitted.

C.2.2 Mount. The weapon shall be supported during testing by mounting in a suitable fixture as required to permit manual operation of the test weapon. The test fixture shall be constructed and mounted so as to prevent fixture movement during testing. It is very important that the weapon maintains its original position from shot to shot.

C.2.3 Targets.

C.2.3.1 Gelatin. 10% by weight ballistic gelatin block.

C.2.3.2 Armor Plate. 1/4 inch thick AR500 hardened steel plate.

C.2.4 Range. The firing range shall be arranged such that a horizontal distance of 15 feet is maintained from the muzzle of the test weapon to the face of the gelatin block or armor plate.

C.3 Test Procedure.

C.3.1 Cartridge Examination. If visual defects are found in the test cartridges prior to testing, the defective cartridge(s) shall be replaced.

C.3.2 Cartridge Conditioning. The required number of test cartridges shall be permitted to come to a temperature of 60F to 80F prior to being placed in the controlled temperature room or container. The cartridges shall be placed in a controlled temperature room or container in such a manner that all the cartridges are subjected to an uniform temperature for a minimum of two hours, prior to firing.

The room or container shall be maintained at 70 2F and be of sufficient capacity to allow free circulation of air.

C.3.3 Weapon Preparation. The test weapon shall be thoroughly cleaned prior to the beginning of testing. The test weapon shall be lubricated using Cleaner, Lubricant and

C-2

Preservative (CLP, MIL-L-63460). The weapon shall be maintained at room temperature for a minimum of two hours prior to the start of testing.

C.3.4 Firing Into Gelatin.

C.3.4.1 The target shall be placed at the required distance downrange. The weapon shall be sighted-in to the center of the target.

C.3.4.2 The test weapon shall be loaded with one cartridge and the projectile shall be fired at the target with NATO angle of 0 5.

C.3.4.3 The gelatin block shall be removed for later analysis and a new block shall be positioned at the required distance downrange.

C.3.4.4 The procedures of C.3.4.2 and C.3.4.3 shall be repeated until a total of four cartridges have been fired.

C.3.4.5 Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.

C.3.5 Firing Onto Armor Plate.

C.3.5.1 The target shall be placed at the required distance downrange. The weapon shall be sighted-in to the center of the target.

C.3.5.3 A witness panel shall be positioned behind the muzzle of the test weapon as specified in Paragraph 4.5.2.4 of the specification to test for reverse splatter.

C.3.5.3 The test weapon shall be loaded with one cartridge and the projectile shall be fired at the target with NATO angle of 0 5.

C.3.5.4 After each shot the plate shall be inspected for penetration and the witness panel shall be inspected for bullet fragments that may have ricocheted back toward the shooter.

C.3.5.5 The procedures of C.3.5.1 through C.3.5.3 shall be repeated until 25 shots have been fired or plate penetration occurs. All shots shall be fired into a maximum 3/4 inch diameter impact area on the plate.

C.3.5.6 If penetration occurs before firing 25 cartridges, the number of shots to produce penetration shall be recorded.

C-3

C.3.5.7 The presence or absence of bullet fragments in the witness panel shall be recorded.

C.3.5.8 Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.

C.4 Examinations. All fired cartridge cases and primers shall be visually examined to determine compliance with the applicable requirements of Table I in the specification. In the event that fired case or primer defects are encountered, or if a misfire occurs, then the test weapon shall be examined to determine if the defect is attributable to the weapon. If the weapon is at fault, then the test shall be disregarded and the weapon shall be repaired or replaced prior to performing a retest. If the defect cannot be attributed to the weapon, then the defect shall be attributed to the cartridges. Misfired cartridges and fired cartridge cases and primers shall be retained for further examination.