I just spent the afternoon doing some more research into the AKA valve situation.
My hunch was correct. Earlier WGP bodies have a LARGER valve chamber bore than the later gun bodies.
I have NO idea when it changed, but it wouldn't surprise me if it happened around when K2 bought WGP. We would need to get more bodies to research that and find out.
I got my hands on an early right feed gun body serial number 68024 and guess what... the valve chamber dimension is 0.583"! That's 0.014" different which is HUGE!
Looks to me like AKA made their valves fit the earlier gun bodies, and then WGP tightened up their bore making all of the AKA valves incompatible from then on.
I do not know why the earlier WGP bodies were larger, as the later WGP bodies have dimensions that make more sense for the threads etc. part of me suspects the K2 engineers "corrected" the WGP dimensions once they took over production. Although with that said, I believe the bodies I am working from were still made under the old WGP hmmm. From a conversation I had with Sonny Lopez he led me to believe they were made at WGP when he was there.
Does anyone know exactly when the WGP unibodies were first released?
Any body with a collection of gun bodies and pin gauges want to help measure and work out when WGP made the change?