I figured as much, felt i had to list both theories though as it may not have been a ruger; i guess we will never know for certain unless TZK leaves a 'time capsule' of sorts for his surviving relatives to open when he's dead and can't be held accountable.. (if he even cared..) & i wasnt too sure if ruger made a 22LR pistol during the time Z was active, ive been having a look into what model it could have been since my original reply.. ~ is it possibly this?

This is the most likely one if it was infact a ruger, the OG "ruger standard" as the wiki calls the first version of the 22LR handgun, was built/sold in 1949.

From what I've read online it was commonly bought for practising self-defense skills/aim though some "ratters" and similar small game hunters used the gun to sneak up and quietly take out an animal without alerting other animals, people probably chose it for the reasons above because of the small caliber. Esp TZK, its easy to imagine that he didn't want to get interrupted.. (fox exterminators/hunters for example, as they don't need a large round to kill a fox.. 22LR is the perfect size really, its relatively quiet, yet fast enough.. & powerful enough to whizz straight through a fox's skull from a decent distance.)

its an extremely german looking gun, reminiscent of a Luger-P08 or a Walther-P38 just with a smaller caliber and thus noise (The former being a german armed forces favourite until the latter replaced it, in well 1938.) The U.S. Army even briefly considered the Luger before turning to the M1911, as irregardless of its good technical reputation, the p08 is said to be a "complicated machine with several downsides"

Which makes me wonder, If z truly had military training or experience of some kind, is it possible he handled a p08 or p38 during the period he was training or active?

Was he a german military fan boy?

What are the chances he chose to use that specific ruger, that just happens to look like a 'nazi' weapon?

ALSO; as years "ticked by" the P08s greatest competitor, was VERY intrestingly the browning hi-point ~ the gun he was handling at berryessa!!