These custom nickel plated socket head screws were produced domestically using 4340 material instead of the originally requested 17-4PH version, with heat treatment to get the parts up to required 35-45 HRC hardness. 1/2-20 thread with 2A thread fit was incorporated with thread length of .77 inches. Overall length underneath the head was set at 1.37" +.00/-.03". The large .945" diameter head presented a challenge from the start for the cold heading operation - it took multiple sets of tooling and adjustments to finally get the head shape just right.
