screws › close tolerance screws
MS27577-4-18
Military Standard Screw
Description
Fastener Length: 1-9/16", Thread: 1/4-28, Thread Length: 21/64"
Specifications
| Countersink Angle | 100.0 degrees |
|---|---|
| Distance From Head Largest Bearing Surface To Shank Hole Center | 1.443 inches minimum first hole and 1.563 inches maximum first hole |
| Fastener Length | 1.543 inches minimum and 1.563 inches maximum |
| Grip Diameter | 0.2483 inches minimum and 0.2492 inches maximum |
| Grip Length | 1.125 inches minimum and 1.141 inches maximum |
| Hardness Rating | 36.0 rockwell c minimum and 41.0 rockwell c maximum |
| Head Diameter | 0.449 inches minimum and 0.507 inches maximum |
| Head Style | Flat countersunk |
| Internal Drive Style | High-torque |
| Length | 1 9/16 |
| Locking Feature | Detent ball grip |
| Material | Steel |
| Material Specification | Mil-b-83050 mil spec single material response |
| Shank Unthreaded Hole Diameter | 0.076 inches minimum first hole and 0.086 inches maximum first hole |
| Surface Finish | 63.0 microinches grip, 63.0 microinches top of head |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Qq-p-416 ty 2 cl 2 fed spec single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.282 inches minimum and 0.333 inches maximum |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series Designator | UNJF |
| Thread Size | 1/4 |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
- MS27577-4-13
- MS27577-4-18
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS27577-4-18. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error