bolts › machine bolts
MS9491-18
Military Standard Machine Bolt
Description
Fastener Length: 1-3/8", Thread: 5/16-24, Thread Length: 7/8
Specifications
| Fastener Length | Between 1.365 inches and 1.385 inches |
|---|---|
| Features Provided | Finished head |
| Grip Length | Between 0.440 inches and 0.500 inches |
| Hardness Rating | 24.0 rockwell c and 35.0 rockwell c |
| Head Height | 0.188 |
| Head Style | Hexagon Head |
| Material | Iron |
| Material Specification | Ams 5731 assn standard single material response |
| Min. Tensile Strength (psi) | 130000 pounds per square inch |
| Minimum Yield Strength | 85000 pounds per square inch |
| Surface Finish | 32.0 microinches bearing surface of head, 32.0 microinches grip, 32.0 microinches threads |
| Thread Class | 3a |
| Thread Diameter | 0.312 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.865 inches and 0.925 inches |
| Thread Qty | 24 |
| Thread Qty Per Inch (tpi) | 24 |
| Thread Series | UNJF |
| Thread Series Designator | Unjf (fine thread with external controlled root radius) |
| Thread Size | 1/4 |
| Width Between Flats | Between 0.492 inches and 0.502 inches |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS9491-18. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error