1、MIL-F-L7724 LO 7779706 0300527 4 I - MIL-F-19924 (Nord) 19 June 1957 MILITARY SPECIFICATION FEED MECHANISMS, 20MM, MARK 7 MODS O AND 2 1. SCOPE 1.1 SCO e. - This specification covers the procurement re- quirements -+ or 20MM Feed Mechanisms Mark 7 Mods O and 2. 1.2 Classification. - Feed mechanisms
2、furnished under this specification shall be of the following Mark and Mods, as speci- fied (see 6.2): Mark 7 Mod O (LD 2764.62) Mark 7 Mod 2 (LD 266061) 2. APPLICABLE DOCUMENTS 2.1 The following specifications standards, drawings, and publications, together with those Lsted on applicable drawings, o
3、f the issue in effect on date of invitation for bids, form a part of this specification: SPECIFICATIONS FEDERAL P-S-566 - Soap, Chip. P-S-661 - Solvent, Dry Cleaning. MILITARY JAN-C-372 - Cleaner, Rifle-Bore. MIL-1-6870 - Inspection Requirements, Non-destructive; MIL-R-15074 - Compound, Corrosion Pr
4、eventive, Finger- MIL-L-l9701(NOrd) - Lubricant, All Weather, Semi-Fluid, for Aircraft Materials and Parts. print Remover . for Aircraft Ordnance. - Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-19924 LO I 799906 O300530 O II . - STANDARDS MI
5、LITARY MIL-STD-10 - Surface Roughness, Waviness, and Lay, MIL-STD-105 - Sampling Procedures and Tables for Inspec- tion by Attributes. MIL-STD-129 - Marking for Shipment and Storage. MIL-STD-130 - Identification Marking of U. S. Military Property. BUREAU OF ORDNANCE NAVORD OSTD 2 - Method of Marking
6、 Ordnance Material, DRAWINGS BUREAU OF ORDNANCE 982519 - 20MM Ammunition for Aircraft Gun Mk 12, Target 982520 - 20MM Ammunition for Aircraft Gun Mk 12, Dummy i500629 - Power Supply Console (for testing 20MM Machine Gun Mk 12 Mods). 151 5855 - General Arrangement Wiring Diagram, Power Sup- ply Conso
7、le (for testing 20MM Machine Gun Mk 12 and Mods). 1591132 - Wiring Diagram, Standard Proofing Equip. LD 172560 - Synchronizing Switch Mk 1 Mod 1. LD 255941 - 20MM Ammunition Link Mk 2 Mod O. LD 256043 - 20MM Ammunition Link Mk 2 Mod 1. LD 256076 - Shipping Container for 20MM Feed Mechanism Mark 7 Mo
8、ds O and 2. LD 266032 - 20MM Aircraft Gun Mk 12 Mod O. LD 256061 - 20MM Feed Mech. Mk 7 Mod 2. LD 276462 - 20MM Feed Mech. Mk 7 Mod O. LD 288830 - 20MM Amnunition Link rvIk 2 Mod 2. LD 413813 - Power Supply Console (For Testing 20MM Ma- chine Gun Mk 12 and Mods). LD 413815 - Standard Proofing Equip.
9、 (for 20MM Gun Mk 12 and 20MM Feed Mech. Mk 7 however, the obliga- tion is on the contractor to satisfy the procuring activity as to full compliance with the contract, the applicable drawings as listed on LD 206061 or LD 276462, and this specification. The contractor shall provide adequate safety de
10、vices to prevent injury to personnel during the tests of 4.3. 3.3 Material. - Material shall conform to the requirements and specifications specified on the applicable drawings. procuring materials the contractor shall provide for material lot formation as specified in 4.1.2.1 and 4.1.2.2. component
11、 parts of the feed mechanisms covered by this specifi- cation shall be in strict accordance with the applicable draw- ings and this specification. In addition, the component parts shall be free from cracks, porosity, voids, scale, or other defects which may make the part unsuitable for the intended
12、purpose . In 3.4 Physical requirements. - The physical requirements of the 3.5 Finishes, coatings and tolerances. - 3.5.1 Surface roughness, waviness, and lay. - Corners, edges, and surfaces shall be finished in strict accordance with drawing requirements and shall be free from any roughness, tool m
13、arks, machining mismatches, or any other discrepancies which would tend to initiate cracks or cause galling or other malfunction. Surface roughness symbols shown on the drawings shall be inter- preted in accordance with Standard MIL-STD-10. 3.5.2 Protective coating. - Unless otherwise specified in t
14、he contract or order, all parts of the feed mechanisms covered by this specification shall be plated, coated, or treated as speci- fied on the applicable drawings. 3.5.3 Dimensions and tolerances. - Dimensions and tolerances shall be in strict accordance with the applicable drawings and this specifi
15、cation. 3.6 Interchangeability. - All parts having the same part num- ber shall be completely interchangeable with each other and with like parts of other manufacture with respect to installation and performance. Parts joined together by welding, brazing, or riv- eting shall be interchangeable as as
16、semblies. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-L772LI LO I 777770b 0300533 b W MIL-F-19924 ( Nord) 3.7 Spare parts. - When procurement documents (see 6.2) stip- ulate that spare parts are to be furnished with assembled feed mechani
17、sm, the spare parts shall be produced concurrently with and of the same material lots as like parts used in the assem- bled feed mechanisms. 3.8 Threads. - Unless otherwise specified on the applicable drawingmthreads shall conform to the National Bureau of Standards Handbook H28, and the not-go prac
18、tice shall be as set forth in the supplement to the aforementioned handbook. The class of fit shall be as specified on the applicable drawings. 3.9 Gages. - The contractor shall provide himself with what- ever gages are necessary to insure that the parts and assemblies covered by this specification
19、will meet the dimensions and tol- erances specified by the applicable drawings. If so desired, and upon request of the contractor, the Government will furnish available drawings of the applicable Government final inspection gages required by the contractor. This procedure shall not serve to relieve
20、the contractor of his responsibility in the de- sign and manufacture of such other gages as may be required to satisfactorily fulfill the contract requirements. 3.10 Identification markine;. - Each component of the feed mechanismshallaccordance with the drawings and Standards NAVORD OSTD 2 and MIL-S
21、TD-130 except that marking with ink on metal parts will not be permitted. 3.11 Lubrication. - Feed mechanisms shall be lubricated in accordance with Publication OP 1912 with a light coating of MIL-L-19701 (Nord). 3.12 Assembly. - Prior to bench tests, cycling tests and firing tests, the feed mechani
22、sms shall be assembled to the hand of feed specified (see 6.2) and serviced in accordance with ap- plicable drawings and Publication OP 1912. There shall be no fitting or alteration of any kind during assembly or operation. 3.13 Government loaned property. - The contractor shall be responsible for a
23、ny damage to Government loaned property. The contractor shall not machine, file, grind, scrape or otherwise modify such property except with the prior approval of the pro- curing activity. 3.14 Government furnished property. - The Government shall furnish any components when specified in the contrac
24、t or order (see 6.2). Immediately upon delivery of Government furnished property, the contractor shall determine whether or not such property is defective or damaged. If such property is found to 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-
25、F-L7724 LO H 7777706 0300534 B Y MIL-FJ9924 (Nord) be defective or damaged, the contractor shall notify the Govern- ment and the Government shall repair or replace defective or damaged property at no expense to the contractor. However, if the Government furnished property is found to be in good cond
26、i- tion and is accepted by the contractor and is subsequently dam- aged or after acceptance by the contractor is found to be de- fective, the responsibility for repairs or replacement shall rest with the contractor. 3.15 Performance. - Feed mechanisms shall perform satisfac- torily when submitted to
27、 the tests described in 4.3.2, 4.3.3, 4.3.4, and 4.3.5. Evidence of any condition which indicates a tendency to gall or bind, or adversely affects rapidity and smoothness of function, or causes undue wear, or indicates the presence of burrs, leakage of air, or other defects, shall be considered as r
28、eason for rejection. The contractor shall cor- rect, without additional expense to the Government, all defects due to improper adjustment, faulty material, or inferior work- manship. 3.15.1 Rate of fire. - The rate of fire (cycle) of the feed mechanism shall be not less than 925 nor more than 1125 r
29、ounds per minute. 3.16 Supplementary requirements. - 3.16.1 Reports of tests. - Accurate reports of parts failure, functional failure, and parts replacement of each feed mechanism, together with the applicable number of rounds fired shall be re- corded. This information, together with an analysis of
30、 any mal- function shall be forwarded to the procuring activity. 3.17 Workmanchip. - The quality of workmanship shall be such as to assure compliance with all the requirements of the appli- cable drawings, standards, and specifications. 4. QUALITY ASSURANCE PROVISIONS AND TEST REQUIREMENTS. 4.1 Samp
31、linZI;. - Unless otherwise specified, and when appli- cable, the sampling plans and procedures used by the Government Inspector in the determination of the acceptability of products submitted by a supplier for Government inspection will be in ac- cordance with the provisions of Standard MIL-STD-105.
32、 6 . i- Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-19924 10 W 393990b 0300535 T-I MIL-F-l9924(NOrd) 4.1.1 Preproduction sample. - Unless otherwise specified (see 4.1.1 .l), preproduction samples manufactured in accordance with 3.1 shall co
33、nsist of 3 left hand and 3 right,hand assem- bled feed mechanisms Mark 7 Mod O or Mod 2 as specified (see 6.2). The sample shall be submitted to the Government inspec- tor for preproduction testing at an activity designated by the procuring activity, for purposes of determining compliance with the r
34、equirements of the contract or order, and the applicable specifications, and drawings. Further production of the feed mechanisms or parts by the contractor prior to the approval of the testing or procuring activity (see 4.3.5.4.1) or completion of inspection and tests on the preproduction sample sha
35、ll be at the contractors risk. Accepted preproduction samples will be- come the property of the procuring activity and will be included in the quantity of feed mechanisms called for in the contract or order. 4.1.1.1 Preproduction sample for a subsequent contract. - If a contractor has previously del
36、ivered feed mechanisms in accord- ance with the requirements of this specification and this product has been found to be satisfactory, the preproduction sample for any subsequent contract or order may be waived at the discretLon of the procuring activity (see 6.2). 4.1.2 Lots. - Materials, assembled
37、 feed mechanisms, and spare parts shallbe submitted for inspection in lots as follows: 4.1.2.1 Material lot. - A material lot shall consist of all raw material of the same kind, or origin, melt or heat, procured and processed into production at the same time, for manufacture of feed mechansms and sp
38、are parts. Each such lot shall. be sub- initted for inspection as prescribed in the applicabla ma+,rrial specification. It shall be arranged in such a manner as to sat- isfy the inspector that all material in the lot is reasonably uniform in quality and characteristics. Feed mechanisms and spare par
39、t lot. - A feed mecha- nism and spare part lot shall consist of assembled feed mecha- nisms and their spare parts as produced concurrently by a manu- facturing process common to the lot. Each lot of assembled feed mechanisms and spare parts shall not include more than one lot of raw material where p
40、arts are subjected to heat treatment. Unless otherwise specified, the number of feed mechanisms and their spare parts in an “inspection lot“ shall not exceed one (1 ) month I s product ion. 4.1.2.2 4.1.2.3 Replacement parts lot. - A replacement parts lot shall consist of all spare parts of the same
41、design presented for acceptance at one time, in which the unit of product is a part manufactured separate from the process of assembled feed mechanism lots (see 4.1.2.2). 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-19924 LO E 999970b 0300
42、536 L m 4.1.2.4 Lot identification. - The contractor shall mark the lot number and when applicable the heat, melt, or other manu- facturing process numbers, directly on the material or parts or containers, in a manner approved by the inspector. Such identi- fications shall be maintained until the xa
43、terial or parts have been accepted. Where identification of raw material by lot num- ber is necessary in the manufacture of parts, such identifica- tion shall be maintained during fabrication of parts. 4.2 Inspection. - 4.2.1 General, - The general inspection and test procedures for contractor inspe
44、ction and Government inspection shall be In accordance with the provisions of Publication OP 400 and this specification. The inspection level, Acceptable Quality Level (AQL), and Ordnance Classification of Defects shall be provided by the procuring activity. 4.2.2 Inspection and test procedures. - R
45、aw materials shall be tested for compliance with the applicable material specifica- tion. Parts and assembled feed mechanisms, spare parts, and re- placement parts selected in accordance with 4.1 shall be visu- ally and dimensionally inspected and tested for mechanical prop- erties and material soun
46、dness in accordance with the Ordnance Classification of Defects, the applicable drawings, and this specification. The tests of 4.3.2, 4.3.3, and 4.3.4 shall be conducted by the contractor at the place of manufacture. The tests of 4.3.5.5 and 4.3.5.6 shall be conducted by the Govern- nient inspector
47、at the testing activity designated by the procur- ing activity (see 6.2). Each preproduction sample (see 4.1.1) shall be subjected to all the inspections and tests of this specification. 4.3 Tests. - 4.3.1 General. - The assembled feed mechanisms comprising each inspection lot (see 4.1.2.2) and each
48、 preproduction sample (see 4.1.1) shall be subjected to bench tests of 4.3.2, func- tional cycling tests of 4.3.3, interchangeability tests of 4.3.4, firing tests of 4.3.5, and post proof visual inspection of 4.4. Spare parts and replacement parts shall be tested in accordance with 4.2.2 and shall m
49、eet the acceptance criteria of 4.5.6 or 4.5.6.1 whichever is applicable. 4.3.2 Bench tests. - Each feed mechanism of the inspection lot shall be subjected to the tests of 4.3.2.1 thru 4.3.2.12 and to 4.3.2.13 as applicable. 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-1972V LO I 7777706 0300537 3 I MIL-F-19924 (Nord) interchangeability of mounting on any receiver for the 20MM Air- craft Gun Mark 12. 4.3.2.2
