MS24677 screw — cylindrical socket head cap, drilled for safety wire (plain or knurled)

Notes from the standard

• Threads per FED-STD-H28/2; acceptability FED-STD-H28/20 System 22. Screws above the heavy line in Table I (threaded_to_head = true) have complete threads to within two threads of the head; rows below it carry the grip length LG max and body length LB min.
• Head may or may not be knurled at the manufacturer's option. Diameter of a knurled head must not exceed the maximum head diameter.
• Drilled hole data: one hole through the head on sizes #4 (.112, Amendment 1) and #6 (.138); three holes on sizes #8 (.164) and larger. On sizes smaller than #8 the hole is centered as close as practicable on a flat of the hexagon socket; on #8 and larger the holes lie within the flats of the socket and must not break the socket corners. Hole edges on the outside of the head are chamfered 45 degrees by 0.010 to 0.020 deep.
• Alignment plug (Table I) shall pass completely through the drilled holes in the head without deflection.
• Sizes 7/16 (.4375, dash 80 to 95) and 7/8 (.875, dash 147 to 158) are inactive for new design.
• Source marking permanent on sizes .190 and larger (manufacturer, government-regulated or private-label distributor symbol).
• Interchangeability: MS24676 was canceled and superseded by MS24677 effective 7 Jul 1975 (MS24676-1 to -170 by MS24677-1 to -170, same dash numbers); MS24677 PNs in government inventory with an added "C" are used until stock is depleted.
• Scanned sheet: lengths per dash in the 3/8, 1/2 and larger columns were assigned by row position and checked with the printed grip pattern; the leading digit of some grip values is faint in the scan.