Posted: 12/11/2008 5:53:11 PM EDT
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Hey guys, I have come up with a idea that I am hoping everyone in here will contribute to. My idea came from having to answer so many questions like "what makes the colt so good and cost so much anyway blah blah blah?" The idea is to include all info on the rifles as proof to be shown on demand. Sort oflike "the chart" but better. Instead of terms like MPI bolt check marked, our thread will hopefully tell what MPI means and the testing and time and QC that goes into this.
Any info will help. Please if you have anything at all post it in this thread. Try not to just post a link but the real data. If you have MIL-STD numbers or MIL-SPEC codes please post them and what they mean. The title of this thread will change once the idea comes together. I know a few of you have already agreed to help with this and I hope all the colt guys will picth in so we can have some facts to counter the endless trolls that feel that brand X the El Heffe special is "just as good"" |
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MIL-C-71186(AR)
lever when the buttstock is positioned in the extended or retracted position shall allow the lock pin to secure the buttstock in position. Pulling the rear end of the release away from the buttst.ock shall allow the buttstock to slide rearward off the lower receiver extension. lever 3.3.2.12 Buffer assembly. The buffer assembly shall function throuah its full ranae of travel under sprinq action without bindln~. The buffer %sembly shall be se~ureiy retained in the lower receiver assembly by the spring loaded buffer retainer and be capable of being disassembled from the lower receiver assembly when the retainer is manually depressed. 3.3.2.13 Receiver extension. The lower receiver extension shall be securely fastened to the lower receiver by means of the receiver end plate being staked to the receiver extension nut. The receiver shall not rotate from its correct position with the release lever in the 6 o’clock position on the vertical centerline. 3.3.3 Upper receiver qroup. 3.3.3.1 Barrel assembly. The barrel shall be free of cracks, seams and other injurious defects and the bore and chamber shall be free of pockets, rings, bulges and other deformations. The chromium plating in the chamber and bore shall be free of nodules, flaking, pits, stripping, anode burns and evidence of etched base steel. Burrs and sharp edges shall be removed from chamber edges, and bolt locking lugs. Scratches or marks occurring in a chamber which otherwise meets the surface roughness requirements, shall be permitted, provided they do not cause marks on the cartridge case of high pressure test cartridge fired in the chamber. 3.3.3.1.1 Barrel assembly straightness. The barrel assembly shall be straight to the extent that a cylindrical plug with a diameter of .2173 + .0001 inches, and six (6) inches in length must drop through the barrel bore of its own weight. Also, a self aligning plug inserted three (3) inches into the barrel bore at the muzzle, shall have a maximum angular deviation from the theoretical axis of zero degrees and three mlnutes(O”3’). 3.3.3.2 Gas tube. The gas tube shall be securely retained to the front sight assembly by the gas tube spring pin. The gas tube shall be free of mutilations and positioned for proper alignment with the bolt carrier key. 3.3.3.3 Handquard. The two~piece handguard shall be held firmly in place by the handguard cap and the spring loaded slip ring in the barrel nut assembly. IWhen the slip ring 1s depressed rearward the handguards shall be capable of being removed. 6 |
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MIL-C-71186(AR) 3.3.4.4.3 Cam Pin. The cam pin shall be retained in the bolt assembly by the firing pin. The cam pin shall move through its full range of travel in the bolt carrier without bindinq. The cam pin shall be capable of being removed from the boltcarrier without removal of the bolt carrier key assembly. The cam pin shall be capable of being disassembled from the bolt and bolt carrier assembly and reassembled 180° about its vertical axis from its original position without causing binding in the assembly. 3.4 Performance characteristics. 3.4.1 HeadsPace. The headspace shall not be less than 1.4646 inches nor more than 1.4706 inches when measured to the .330 inch datum diameter on the first shoulder of the chamber. 3.4.2 Firinq pin indent. when the bolt is closed and the firing mechanism is released, the firing pin indent shall be not less than 0.020 inch. The firing pin indent shall not be offcenter more than one half the maximum diameter of the indent. When, in a vertical, muzzle down position, the bolt carrier assembly is released from the full recoil position and the firing mechanism is not actuated, the firing pin indent shall not be more that 0.008 inch. 3.4.3 Triqqer Pull. The trigger pull shall be free of creep end shall be within the range of 5.5 to 8.5 pounds. Creep shall be interpreted to mean any perceptible rough movement between the time the trigger slack is taken up and the hammer is released. After partial or complete trigger pull, the trigger shall return to its normal forward position (cocked and uncocked) under spring action. 3.4.4 Hiqh pressure resistance. Each barrel assembly end bolt shall withstand the firing of one Government standard M19?, 5.56mm high pressure test cartridge conforming to MIL-C-46936. After proof firing, parts shall be free of cracks, seems and other injurious defects as evidenced by visual and magnetic particle inspection. 3.4.5 Functioning. Each carbine shall operate without malfunctions or unserviceable parts. The cyclic rate of fire for a 30 round continuous burst using a 30 round magazine shall be within 700 to 97o rounds per minute when firing Government standard t4855, 5.56mm ball cartridges conforming to MIL-C-63989. 3.4.6 Tarqetinq and accuracy. A series of 10 rounds fired from each carbine at a range of 91.4 meters shall be within the extreme spread and targeting area (heavy outline) specified in Figure I when the front and rear sights are set as follows. The normal rear sight peep (sight rotated fully rearward) shall be used with the rear sight set centrally in the slot for windage |
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4.7.4 High-pressure resistance test. This test shall be
performed during individual carbine testing in accordance with TABLE III, using a fixture for holding the bolt and barrel assembly per drawing 11837944. 4.7.4.1 Test cartridqe. One (1) high-pressure test cartridge (see 3.4.4) shall be fired in each bolt and barrel assembly. Unless otherwise specified, the bolt and barrel assembly shall be tested concurrently. After proof firing, cartridge cases shell be examined for bulges, splits, rings and other defects caused by defective chambers of the barrel assembly. 4.7.4.2 Barrel inspection. The barrel assembly shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing a current of 400 to 500 amperes for circular continuous magnetization. The barrel assembly shall be examined for evidence of cracks, seams and other injurious defects. 4.7.4.3 Bolt inspection. The bolt shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing standard five turn magnetizing coil with a current of 200 to 300 amperes. Both circular and longitudinal continuous magnetization with wet fluorescent solution shall be used. The bolts shall be examined defects. for evidence of cracks, seams and other injurious. |
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Colt 800-962-COLT
CC001616 and Below - Pre-Ban CH019500 and Below - Pre-Ban GC018500 and Below - Pre-Ban LH011326 and Below - Pre-Ban MH086020 and Below - Pre-Ban NL004800 and Below - Pre-Ban SL027246 and Below - Pre-Ban SP360200 and Below - Pre-Ban 1963 SP00001-SP00023** 1964 SP00101 1965 SP02501 1966 SP05600 1967 SP08250 1968 SP10750 1969 SP14000-SP14653 1970 SP15001-SP15473 1971 SP16001 1972 SP19401 1973 SP24201 1974 SP32601 1975 SP43801 1976 SP55301 1977 SP67651 1978 SP83400 ST038100 and Below - Pre-Ban TA10100 and Below - Pre-Ban BD000134 and Below - Pre-Ban (AR-15A3 Tactical Carbine - very rare model) MT00001 and Above - Post-Ban BK000001and Above - Post Ban (CAR-A3) CST000001 and Above - Post-Ban (Began Late 1997 Production) CMH000001 and Above - Post Ban CCH010000 and Above - Post Ban MT6700, MT6700C and MT6700CH series, 1998 production |
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3.3.2.13 Receiver extension. The lower receiver extension
shall be securely fastened to the lower receiver by means of the receiver end plate being staked to the receiver extension nut. The receiver shall not rotate from its correct position with the release lever in the 6 o’clock position on the vertical centerline. 3.3.3 Upper receiver qroup. 3.3.3.1 Barrel assembly. The barrel shall be free of cracks, seams and other injurious defects and the bore and chamber shall be free of pockets, rings, bulges and other deformations. The chromium plating in the chamber and bore shall be free of nodules, flaking, pits, stripping, anode burns and evidence of etched base steel. Burrs and sharp edges shall be removed from chamber edges, and bolt locking lugs. Scratches or marks occurring in a chamber which otherwise meets the surface roughness requirements, shall be permitted, provided they do not cause marks on the cartridge case of high pressure test cartridge fired in the chamber. 3.3.3.1.1 Barrel assembly straightness. The barrel assembly shall be straight to the extent that a cylindrical plug with a diameter of .2173 + .0001 inches, and six (6) inches in length must drop through the barrel bore of its own weight. Also, a self aligning plug inserted three (3) inches into the barrel bore at the muzzle, shall have a maximum angular deviation from the theoretical axis of zero degrees and three mlnutes(O”3’). 3.3.3.2 Gas tube. The gas tube shall be securely retained to the front sight assembly by the gas tube spring pin. The gas tube shall be free of mutilations and positioned for proper alignment with the bolt carrier key. 3.3.3.3 Handquard. The two~piece handguard shall be held firmly in place by the handguard cap and the spring loaded slip ring in the barrel nut assembly. IWhen the slip ring 1s depressed rearward the handguards shall be capable of being removed. 6 MIL- |
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3.7 workmanship. Workmanship shall be in accordance with
the workmanship requirements of MIL-w-13855. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. unless otherwise specified in the contract or purchase order, the supplier is responsible for the performance of all inspection requirements (examinations and tests) as specified herein. Except as otherwise specified in the contract or purchase order, the supplier may use his own or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to ensure supplies and services conform to prescribed requirements 4.1.1 Responsibility for compliance. All items shall meet all requirements of Sections 3 and 5. The inspection 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 conunit the Government to accept defective material |
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HERE IS A BIT I FIND VERY INTERESTING. THIS IS A REALLY GOOD FING
4.4.1 Submission. The contractor shall submit a first article sample as designated by the Contracting Officer (see 6.2) for evaluation in accordance with the provisions of 4.4.2. The first article shall be a representative of the production processes to be used during quantity production and shall of the items listed below in the quantities indicated. consist |
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4.4.2 Inspections to be performed. As determined by the
@vernment, the first article assemblies, components and test specimens shall be subjected to all of the examinations and tests specified below, and may be inspected for compliance with any or all requirements of the applicable drawings. Test a. Headspace Trigger pull Firing Pin Protrusion High Pressure Resistance i?unction/Cyclic Rate of Fire Targeting and Accuracy Interchangeability Endurance Examination Number To Test 11 Requirement 3.4.1 3.4.2 3.3.4.2 3.4.3 3.4.4 3.4.5 3.5 3.4.6 3.3, 3.6 Test Method 4.7.1 4.7.3 4.7.2 4.7.4 4.7.5 - 4.5.5.3.5 4.7.6 - 4.7.6.2.1 4.7.7.1 4.7.8 - 4.7.8.4.5 4.5.2.2 4.5.1.1.1 Inspection lot formation. The formation and presentation of inspection lots shall be in accordance with MILW- 13855. Lot formation shall be established after final inspection of carbines by the contractor and prior to conducting test specified in TABLE IV. 4.5.1.1.2 Lot size. unless otherwise specified herein, an inspection lot shall consist of 1,000 carbines or a single month’s production, whichever 1s smaller. These carbines shall be assembled from lots of component parts that have met all inspection requirements. 4.5.1.1.3 Lot identification. Each inspection lot shall be identified with a lot number. The serial number of each carbine in a lot shall be recorded on the individual carbine record. The reason for rejection of any inspection lot shall be recorded. When a rejected inspection lot is resubmitted after reconditioning, it shall be identified as such. |
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4.5.2.2.1 Inspection app roval stamp. Carbines which have
passed all examinations after successful completion of testing shall be rubber stamped by the contractor with the Department of Defense complete inspection approval stamp on the-packaging list of each shipping container. The Government representative will control the stamps used for such stampings required to assure successful completion of all required examinations and tests. 31 4.5.2.3 Component parts and concurrent repair parts. Examination of component parts and concurrent repair parts shall be performed in accordance with the criteria as specified in the contract (see 6.2). Examination of these parts shall be accomplished prior to their assembly into the end item or submitting for acceptance as repair parts. 4.5.2.4 Packaqinq. Examination of packaging of carbines shall be performed in accordance with the Classification of Defects specified in 4.5.2.4.1. Sample size and acceptance criteria for each lot shall be in accordance with TABLE II, using the inspection levels stated in the Classification of Defects. A visual inspection shall be performed to assure that the criteria specified in the contract (see 6.2) result in the parts and packages meeting the acceptance criteria. Packages opened for examination shall be repackaged by the contractor at the contractor’s expense (see 6.2). |
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Workmanship
~/ unless otherwise specified in the contract, the packaging requirements are specified on Special Packaging Instruction 12972700 as applicable. ~1 Examination for packaging defects specified above shall aPPIY to each sample of carbines, interior packages or exterior containers as applicable. 4.5.3.1 Carbine Testinq. Individual carbines shall be subjected to the tests specified in TABLE III. Inspection lots of carbines shall be subjected to the tests specified in TABLE IV. sample size, acceptance criteria and test methods for each test shall be as specified in TABLE III and TABLE IV. The Government representative shall randomly select carbines to be subjected to the endurance test and interchangeability test from inspection lots that met the requirements of 4.5.2. Component parts to be subjected to the concurrent repair parts interchangeability test shall be randomly selected from accepted component inspection lots concurrently being used in the assembly of the carbines ~/ Failure of the sample, unless otherwise specified in the applicable test method, to meet the requirements shall cause rejection of the represented lot. ~1 Failure of one carbine in the sample of thirty-two to meet the requirements shall cause a second sample to be tested from the same lot. The second sample shall consist of thirty-two carbines, exclusive of the first thirty-two, (cumulative, sixtyfour carbines). Failure of two or more carbines in the first sample or the combined first and second sample shall be cause for rejection of the represented lot. 3/ The 30 round magazines selected for the endurance test shal~ be visually and manually inspected by the contractor for workmanship and completeness of assembly and determined to be satisfactory prior to test. ~1 The sample shall be selected from each inspection lot of repair parts. 5/ when carbines are produced concurrently by more then one manul?acturer, each manufacturer shall forward five carbines monthly (see 6.2) for the interplant interchangeability test. The contractor will be informed of any failure of the carbines to meet the prescribed requirements. ~1 when five successive inspection lots meet the requirements, the inspection lot size shall be increased to 5000 carbines or a month’s production, whichever is smaller. |
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MIL-C_71186(AR) 4.7.3 Trigqer pull test. This test shall be performed during individual carbine testing in accordance with TABLE III using Government approved inspection equipment. 4.7.3.1 Minimum load. The carbine shall be cocked and the selector lever placed in the “SEMI” position. The minimum load shall be gradually applied to the center of the trigger and exerted in line parallel to the axis of the barrel bore. To be acceptable, the hammer shall not release. 4.7.3.2 Maximum load. The carbine shall be cocked and the maximum load shall be gradually applied to the center of the trigger as before. To be acceptable, the hammer shall release. 4.7.3.3 Creep. The carbine shall also be manually tested to assure that the trigger pull is free of creep (see 3.4.3) and that the trigger returns under spring action to its normal forward position after partial or complete trigger pull. 4.7.4 High-pressure resistance test. This test shall be performed during individual carbine testing in accordance with TABLE III, using a fixture for holding the bolt and barrel assembly per drawing 11837944. 4.7.4.1 Test cartridqe. One (1) high-pressure test cartridge (see 3.4.4) shall be fired in each bolt and barrel assembly. Unless otherwise specified, the bolt and barrel assembly shall be tested concurrently. After proof firing, cartridge cases shell be examined for bulges, splits, rings and other defects caused by defective chambers of the barrel assembly. 4.7.4.2 Barrel inspection. The barrel assembly shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing a current of 400 to 500 amperes for circular continuous magnetization. The barrel assembly shall be examined for evidence of cracks, seams and other injurious defects. 4.7.4.3 Bolt inspection. The bolt shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing standard five turn magnetizing coil with a current of 200 to 300 amperes. Both circular and longitudinal continuous magnetization with wet fluorescent solution shall be used. The bolts shall be examined defects. for evidence of cracks, seams and other injurious 38 |
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Serial Number Prefix
Model Name Sample Model BD AR15A3 Tactical Carbine 6721 CC Colt Carbine R6520 CH Competition HBAR 6700 GC Government Carbine 6520 GS Governmodel Model Service 6550 MH Match HBAR 6601 ML Match Lightweight R6530 MT Match Target SP Sporter SP1 or SP2 ST Sporter Target 6551 TA 9mm 6450 6430 |
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Barrel Manufacturing Stampings
Manufacturing StampMeaning MP Magnetic Particle Tested C Chromed Chamber CB Chromed Bore HBAR HBAR Barrel Profile Barrel Stamping Methodology Manufacturer Quality Control Caliber Barrel Twist MISC Examples C MP CHROME BORE Colt Magnafluxed with a chrome lined bore C MP 5.56 NATO 1/9 HBAR Colt Magnafluxed, in 5.56 NATO, 1 in 9 twist, with a HBAR profile |
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Quoted:
For my next dumb question.... What about Saber defense. I didn't see that listed among the tier 1 rifles. Is there a reason? no offense, but this isnt the sabre forum or the sabre MILSPEC forum/thread.. but to help you out a little. the M16s sabre makes for ther GOV. are made under the TDP owned by colt. basically they have colts permission to make a copy of colts gun. The only time they can use the TDP is for gov contracts and not the civilian world. any civi ARs sabre makes are reversed engineered. BTW I would count Sabre as in the 1st tier, but not the number 1 
anything eles non colt related please IM me. this thread wasnt meant to answer questions about other companies 
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MIL-STD-1949A
3. DEFINITION 3.1 Ambient light. The visible light level measured at the Specimen surface with the black light on. 3.2 Alternating current. An electrical current that reverses it@ direction of flow at regular intervals. 3.3 Black light. Electromagnetic radiation in the near ultraviolet range of wavelengths 320 t 380 nanometers (1 nm = lCI-9meters) with those wavelengths near 365 nm predominating. 3.4 Classification. The initial review of a visible magnetic particle accumulation to decide if it is held on the test piece by magnetic means or by non-magnetic means (i.e. if it is a relevant, non-relevant or false indication). 3.5 Coil 8hOt. Production of longitudinal magnetization accomplished by passing current through a coil encircling the part being inspected. 3.6 Conditioned water. Water with an additive or additives which impart specific properties such as proper wetting, particle dispersion, or corrosion resistance. 3.7 Continuous method. The continuous method of examination consists of applying or otherwise making available on the surface of the piece an ample amount of magnetic particles to form satisfactory indications while the magnetizing force is being applied. 3.8 Contracting agency. ,A prime contractor, subcontractor or government agency procuring magnetic particle inspection services. 3.9 Defect. An unintended discontinuity with size, shape, orientation or location which makes it detrimental to the useful service of the part. 3.10 Flux leakage. A local distortion of the normal magnetic flux pattern of a magnetized part caused by a discontinuity in the part. 3.11 Pull wave rectified alternating current. A full wave rectified single or three-phase alternating current. 3.12 Gauss. This is the unit of flux density or induction in the centimeter, gram, seconds electromagnetic unit system. (1 gauss = 10-4 tesla) (In air 1 gauss is equivalent to 1 oersted which equals 79.58 amps per meter). 3.13 Half wave rectified alternating current. A rectified single phase alternating current that produces a pulsating unidirectional field. 3.14 Head Shot. Producing circular magnetization by passing current directly through the part being inspected while being held in contact with the head stocks in a horizontal wet machine. 3.15 Indication. An accumulation of magnetic particles on the test piece |
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MIL-STD-1949A
4. GENERAL R!Y2UIREF!ENTS 4.1 Principles of magnetic particle inspection. 4.1.1 Intended use of magnetic particle inspection. The magnetic particle inspection method is used to detect cracks, laps, seams, inclusions, and other surface or slightly subsurface discontinuities in ferromagnetic materials. Magnetic particle inspection may be applied to raw material, billets, finished and semifinished materials, welds, and In-se;vice parts. Magnetic particle inspection is not applicable to nonferromagnetic metals and alloys such as austenitic stainless steels. 4.1.2 Basic principle. The method is based on the principle that the magnetic flux near the surface of a magnetized material is distorted locally by the presence of discontinuities. This distortion of the field pattern, termed “flux leakage=, is capable of attracting and holding an inspection medium of finely divided magnetic particles. The resulting accumulation of particles will be visible under the proper lighting conditions. Sensitivity is greatest for discontinuities at the surface. 4.1.3 Magnetization and particle application. Magnetic particle inspection consists of magnetization of the area to be inspected, application of suitably prepared magnetic particles while the-area is magnetized or being magnetized, and subsequent classification, interpretation, and evaluation of any resulting particle accumulations. Maximum detectability occurs when the discontinuity has a depth at least five times its opening, a length at least equal to its depth, and is positioned perpendicular to the magnetic flux. In order to detect discontinuties in all directions at least two magn,eticfields, perpendicular to one another in a plane parallel to the surface being inspected shall be used, except when specifically exempted by the contracting agency. 4.2 Qualification of inspection personnel. All personnel performing magnetic particle inspection shall be qualified and certified in accordance with MIL-STD-41O. Personnel making accept/reject decisions in accordance with the process described by this standard shall be qualified to at least a level II per MIL-STD-41O. Personnel performing the processing steps described in this standard shall be qualified to at least a level I per MIL-STD-41O. 4.3 Acceptance requirements. The acceptance requirements applicable to the part or group of parts shall be incorporated as part of a written procedure either specifically or by reference to other applicable documents such as MIL-sTD-350 containing the necessary information. Applicable drawings or other’documents shall specify the acceptable size and concentration of discontinuities for the component, with zoning of unique areas as required by design requirements. These acceptance requirements shall be as approved or as specified by the contracting agency 4.4 Written procedure. Magnetic particle inspection shall be performed in accordance with a wzitten procedure applicable to the parts or group of parts under test. The procedure shall be in accordance with the requirements and guidelines of this standard. The procedure shall be capable of detecting the smallest rejectable discontinuities specified in the acceptance |
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MIL-STD-1949A
requirements, The written procedure may be a general one if it clearly applies to all the specified parts being tested and meets the requirements of \. this standard. All written procedures shall be approved by an individual qualified and certified to MIL-STD-41O, Level III for magnetic particle inspection, and shall be submitted upon request to the contracting agency. 4.4.1 Elements of the written procedure. The written procedure shall include at least the following elements, either directly or by reference to the applicable documents: a. b. c. d. e. f. i. j. k. 1. m. n. 0. Identification of the parts to which the procedure applies. This shall include the material and alloy of which the parts are fabricated. Identification of test parts used for system performance verification (see 5.7.2 and 5.7.3). Areas of the part to be examined (include a sketch if necessary). Directions of magnetization to be used, the order in which they are applied, and any demagnetization procedures to be used between shots. Method of establishing the magnetization (prods yoke cable wrap etc). Directions for positioning the item with respect to the magnetizing equipment The type of magnetizing current and the equipment to be used. The current level, or the number of ampere-turns to be used and the duration of its application. Part preparation required before testing. Type of magnetic particle material (dry or wet, visible or fluorescent, etc.) to be used, the method and equipment to be used for its application, and, for the case of wet particles, the particle concentration limits. Type of records and method of marking of parts after inspection. Acceptance requirements, to be used for evaluating indications and disposition of parts after evaluation. Post-inspection demagnetization and cleaning requirements. The procedure identification number and the date it was written. Sequence of magnetic particle inspection as related to manufacturing process operations. 4.5 Record of inspection. The results of all magnetic particle inspections shall be recorded. All recorded results shall be identified, filed, and made available to the contracting agency upon request. Records shall provide for traceability to the specific part or lot inspected, and shall identify the inspection contractor or facility and the procedures used in the inspection. 4;6 Magnetizing and demagnetizing equiPment. Performance of a satisfactory magnetic particle inspection requires magnetization of the part to a specified level in a specified direction. Magnetization can be accomplished either by passing an electric current directly through the material (direct method), by inducing a current to flow in the part under test (induced current method), or by placing the material within the magnetic flux of an external source such as a coil (indirect method). The types of equipment available include yokes, portable units, mobile units, stationary units, and special application units (e.g. a unit to produce a single or .— multidirectional field). |
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Based upon the info shawnmt6601 provided I wanted to add a couple basic pictures for those whom are unframiliar with MT. I will not go into the formula for figuring out the amperage, hysteresis curve, the UV lightlevels, demagnitization etc.... or other methods such as yokes, prods. I just wanted to say that so that some other Level III doesn't chime in and jump on me for not giving all the info. Level III's have a tendancy to always want to out do each other.
4.7.4.2 Barrel inspection. The barrel assembly shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing a current of 400 to 500 amperes for circular continuous magnetization. The barrel assembly shall be examined for evidence of cracks, seams and other injurious defects. 
4.7.4.3 Bolt inspection. The bolt shall be magnetic particle inspected in accordance with MIL-STD-1949 utilizing standard five turn magnetizing coil with a current of 200 to 300 amperes. Both circular and longitudinal continuous magnetization with wet fluorescent solution shall be used. 
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Quoted:
Amazing thread shawn this should be stickied and this goes to show the reason why colt and LMT are more expensive and the reason for spending the extra dough is all in the quality of the parts and the history of the rifle. The funny thing is, you can spend just as much now for a bushy or other brand X and not get the QC that goes into a Colt. It pays to do your homework. |