The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-300-2931, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. Government technical data includes 27 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-300-2931 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Status | ACTIVE |
| Surface Finish | 63.0 MICROINCHES GRIP |
| Surface Finish | 63.0 MICROINCHES BEARING SURFACE OF HEAD |
| Head Height | 0.251 INCHES MINIMUM AND 0.266 INCHES MAXIMUM IN |
| Fastener Length | 2.958 INCHES MINIMUM AND 2.978 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY2 CL2 FED SPEC SINGLE TREATMENT RESPONSE FASTENER |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE STAND-OFF |
| Thread Length | 0.401 INCHES MINIMUM AND 0.546 INCHES MAXIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 41.0 ROCKWELL C MAXIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.106 INCHES MINIMUM AND 0.116 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | AMS5643 ASSN STD 1ST MATERIAL RESPONSE OR AMS5644 ASSN STD 2ND MATERIAL RESPONSE OR QQ-S-763 CL440C FED SPEC 3RD MATERIAL RESPONSE STAND-OFF |
| Material Document and Classification | MIL-S-5000 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-5626 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC 3RD MATERIAL RESPONSE OR MIL-S-6758 MIL SPEC 4TH MATERIAL RESPONSE OR MIL-S-8503 MIL SPEC 5TH MATERIAL RESPONSE FASTENER |
| Nominal Thread Diameter | 0.500 INCHES IN |
| Head Style | CROWNED HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 2.312 INCHES MINIMUM AND 2.328 INCHES MAXIMUM IN |
| Width Between Flats | 0.741 INCHES MINIMUM AND 0.752 INCHES MAXIMUM IN |
| Grip Diameter | 0.4982 INCHES MINIMUM AND 0.4991 INCHES MAXIMUM IN |
| Locking Feature | RETAINER GRIP |
| Surface Treatment | PASSIVATE STAND-OFF |
| Surface Treatment | CADMIUM OR CHROMATE FASTENER |
| Minimum Tensile Strength | 95000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | STEEL COMP 630 OR STEEL COMP 631 OR STEEL COMP 440C STAND-OFF |
| Material | STEEL COMP E4340 OR STEEL COMP 4140 OR STEEL COMP 8740 OR STEEL COMP 4130 OR STEEL COMP 6150 FASTENER |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 2.848 INCHES MINIMUM AND 2.858 INCHES MAXIMUM FIRST HOLE IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| MS27576-8-37 | 5/9 Secondary reference U.S. Government activity |
| MS27576-8-37 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5306-01-300-2931 is a Bolt,close Tolerance, classified under FSC 5306, Bolts. Status: active.
Key specifications for 5306-01-300-2931: Surface Finish: 63.0 MICROINCHES GRIP; Surface Finish: 63.0 MICROINCHES BEARING SURFACE OF HEAD; Head Height: 0.251 INCHES MINIMUM AND 0.266 INCHES MAXIMUM IN; Fastener Length: 2.958 INCHES MINIMUM AND 2.978 INCHES MAXIMUM IN. 27 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.