IHC | Aperature | B8868-1 | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | Late version. Squared ramp shoulders below aperature disk. Wide tracks (0.085 inches wide). Edges of aperture disk smoothly finished. |
IHC | Barrel | D6535448 | N/A | January/1953 to November/1956 | 4400000 - 5278245 | Manufactured by Line Material Compay. Barrels are marked with date and "LMR". Date should be within a few months of Receiver manufacture date. |
IHC | Bolt | 6528287 IHC | U | January/1954 to December/1956 | 5000501 - 5278245 | Hole in bottom. "U" is heat lot, doesn not indicate Underwood manufacture. |
IHC | Bolt | D-6528287IHC | U | January/1953 to December/1954 | 4400000 - 4660000 | Hole in bottom. "U" in heat lot identification, does not indicate Uderwood manufacture. |
IHC | Bolt | D6528287 IHC | U | January/1954 to December/1956 | 5000501 - 5278245 | Hole in bottom. "U" is heat lot, doesn not indicate Underwood manufacture. |
IHC | Bullet Guide | B8875 | Type 5 | January/1953 to December/1956 | 4400000 - 5278245 | Stamped steel, wide slot. Notch 0.25 inch in radius on upper left side. |
IHC | Buttplate Assembly | C64283 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Cap, 11.5 squares in vertical row intersecting screw hole. |
IHC | Clip Ejector | C46018 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | parkerized |
IHC | Clip Latch | C46011 | Springfield 2 | January/1953 to December/1956 | 4400000 - 5278245 | Squared front end, inspector's initials("A" or "C") beside spring retaining hole on inside |
IHC | Clip Latch Pin | N/A | N/A | January/1953 to December/1956 | 4400000 - 5278245 | 3.280 inches long,head is 0.155 inches in diameter and 0.065 inches high. Opposite end slightly rounded. Body of pin is 0.119 inches in diameter. |
IHC | Clip Latch Spring | N/A | N/A | January/1953 to December/1956 | 4400000 - 5278245 | 0.03 inch steel wire, 5 coils, outside diameter 0.26 inch. White finish is original, Parkerized indicates refinishing. |
IHC | Elevating Pinion | N/A | Type 4 | January/1953 to December/1956 | 4400000 - 5278245 | Postwar with 8-36NF thread, no locking bar |
IHC | Elevation Knob | N/A | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Postwar, integral part of pinion, may be marked "IHC DRC". |
IHC | Extractor | N/A | N/A | January/1953 to December/1956 | 4400000 - 5278245 | Parkerized. |
IHC | Extractor Spring and Plunger | B8886 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | |
IHC | Firing Pin | B8879 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | Half round cross section. |
IHC | Follower and Slide | N/A | Type 2F | January/1953 to December/1956 | 4400000 - 5278245 | Unmarked. |
IHC | Follower Arm | B8869 | Type 4 | January/1953 to December/1956 | 4400000 - 5278245 | No bevel, rounded follower arm pin lugs. Unmarked. |
IHC | Follower Arm Pin | A13667 | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | No rebate on either end, straight shaft. |
IHC | Follower Rod | C64331 | Type 5 | January/1953 to December/1956 | 4660001 - 5793847 | Stamped sheet metal. Long fork plate riveted. No marking. Grooves/knurls eliminated. |
IHC | Front Hand Guard | C64245 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | |
IHC | Front Site | B147427 | Type 3C | January/1953 to December/1956 | 4400000 - 5278245 | 0.875 inches wide at blades. Widest of all manufactured. |
IHC | Front Site Screw | N/A | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | Non-rebated head. Head may be smooth or knurled. |
IHC | Gas Cylinder | D35449 | Type 2C | January/1953 to December/1956 | 4400000 - 5278245 | .575 - .580 inch front sight base, flat top on rear ring, unmarked. May show numbers or letters for machinist's marks. |
IHC | Gas Cylinder Lock | B147426 | Type 3A | January/1953 to December/1956 | 4400000 - 5278245 | Front face not chamfered. Hardened, high hump with square edges. Unmarked. 1.455 inches high. |
IHC | Gas Cylinder Lock Screw(Plug) | B7310079 | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | Return poppet valve, cross shaped slot. Marked "IHC" or "IHC NHC". |
IHC | Hammer | 5546008IHC | Type 2C | January/1954 to December/1956 | 5010001 - 5278245 | Drawing number on face, early hooks, no tooling hole. |
IHC | Hammer | 5546008IHC | Type 2D | January/1954 to November/1956 | 5010001 - 5278245 | Drawing number on face, early hooks, letter stamped above drawing number, no tooling hole. |
IHC | Hammer | C-5546008 IHC | Type 2A | January/1953 to November/1954 | 4440000 - 4500000 | Drawing number on face, late hooks, no tooling hole. |
IHC | Hammer | IHC C5546008 | Type 2B | January/1954 to November/1956 | 4500001 - 5010000 | Drawing number on face, early hooks, no tooling hole. |
IHC | Hammer Pin | A13668 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | |
IHC | Hammer Spring | B8887 | N/A | January/1952 to December/1956 | 4400000 - 5278245 | 20 coils |
IHC | Hammer Spring Housing | B8883 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | |
IHC | Hammer Spring Plunger | B8880 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | 1.50 inches long, "wingless" head, 0.40 inches wide. |
IHC | Handguard Clip | N/A | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | Stamped steel, flat profile, no groove. |
IHC | Handguard Ferrule | N/A | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Lip protruding .06 inches from rear barrel hole. |
IHC | Handguard Liner | B8893 | Type 4 | January/1953 to December/1956 | 4400000 - 5278245 | Unmarked. No front or rear hole. Notch is .70 inches wide by .15 inches deep. |
IHC | Lower Band | C46000 | Type 3 | January/1953 to December/1957 | 4400000 - 5278245 | Stamped flat profile with no groove or scallops. Unmarked. |
IHC | Lower Band Pin | N/A | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Roll pin. |
IHC | Operating Rod | 6535382 IHC | 10 | December/1955 to December/1956 | 5100000 - 5278245 | Straight bolt lug, 5/16 radius cut, flat side, marking on bottom. May have a letter marking below drawing number on late production. |
IHC | Operating Rod | D-6535382 IHC | 10 | January/1953 to December/1954 | 4400000 - 4660000 | Straight bolt lug, 5/16 radius cut, flat side, marking on bottom |
IHC | Operating Rod | D6535382 IHC | 10 | January/1954 to December/1955 | 5000501 - 5150000 | Straight bolt lug, 5/16 radius cut, flat side, marking on bottom |
IHC | Operating Rod Catch Assembly | C46027 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Early unmarked, later marked "B,C,F,G,H, or I". Right fork 0.10 in wide and Left fork 0.07 in wide, width at accelerator rivet 0.79 in. |
IHC | Operating Rod Spring | SA14675/B147658 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | Round cross section. |
IHC | Rear Hand Guard | C46024 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | Operating rod clearance cut on right rear. |
IHC | Rear Sight Base | C46001 | Type 2 | January/1953 to December/1956 | 4400000 - 5278245 | may be stamped "A" or "C" |
IHC | Rear Sight Cover | B8872 | N/A | January/1953 to December/1956 | 4400000 - 5278245 | Similar to Type 2 SA. |
IHC | Rear Sight Lock Nut | N/A | Type 3 | January/1953 to December/1956 | 4400000 - 5278245 | Windage knob nut. |
IHC | Receiver | D6528291-C | N/A | January/1953 to December/1953 | 4400000 - 4660000 | |
IHC | Receiver | D6528291-D | N/A | January/1953 to December/1953 | 4400000 - 4660000 | |