Swamplord did 500 Jeff wildcats 6-7 years ago. My guess is brass quality and too much of a good thing is why you dont hear about them anymore.
You are correct on the 500 Jeffery brass issue, Jamison brass was limited in availability then ceased to exist, Bertram was expensive one shot trinkets that lost pockets before ever getting near any velocity generating pressures, Norma brass got me the velocities but only lasted a couple shots, tons of work necking down the .510" ID to .338" & .308", one of the issues I had, was a short throat in order to make the Wolverine function in AICS CIP 3.850" mags and the other problem was the 45-50k psi 500 Jeffery brass just wasn't up to the task
Currently my 500 Jeffery based wildcats have been extensively redesigned based on all the testing and learning I've done along with the advent of the 4.025" internal dims magazines I'm working with now .... On the updated case design I've dropped the Werewolf, Vampyre and Mjolnir names because folks had a hard time with the different names and I was told to cease & desist in use of the "300 Werewolf" due to an existing cartridge with that name,
My original 338 Wolverine prints are dated 2012 so I tossed all the other names and versions, reverted to the Wolverine name for all, with the new updated case design
300 Wolverine, 8mm Wolverine, 338 Wolverine, 358 Wolverine and 375 Wolverine
Brass is currently in production for the 300 & 338 for myself and another gentleman is having brass made for the 358 Wolverine that he will be testing a new super high bc 358 cal ELR bullet in
ONE set of bushing dies with multiple bushings will be able to reload all of these cartridges and the first sets are being made now
I know this thread is about a hot 30 cal but I Don't have a 300 W pc of brass yet but here is what the 338 Wolverine looks like next to the 338 XC
Velocities shown are in the original version with the short throat, 32" 1:10 Twist Benchmark barrel with Norma brass, Berger 300 gr OTM bullets & N570 powder
velocity goal was achieved in the testing trials but an extreme amount of work was involved in getting to the ready to load brass stage, Then fired 2-3 times and primer pockets were gone,
This time around I am having brass made to specs for the new version, ready to load & shoot ... The 300 Wolverine will be burning powder right next to the 338 Wolverine
case h20 capacities were done by me with a fired primer seated, dry case zeroed on scale then weighed with water to top of case mouth, photo's show the most consistent, repeatable h20 weights