[Austin W Hogan]

Thanks Dave. I have a feeling that this is some how related to hardness. Look at a hammer gun, and the hammer is almost always deformed, but the anvil rarely is. That striking area must be deep and hard; a special case hardening was probably necessary to encase the anvil, without making it brittle. The anvil is 1/2 inch long and 5/16 diameter; the firing pin is 1/2 inch long, 3/16 at the joint and 1/8 where it hits the primer. Case hardening this as one piece would have left little ductile steel in the pin inself, resulting in early fracture and failure.
The real question is ; "how did Parker (King) join these parts". A weld might have nullified the hardening process; a swage would have been difficult considering the hardness of the anvil.

Best, Austin