I have a 9mm barrel for my cz52 and only used it once. It came with the gun and functioned fine with ball ammo as I recall but I switched back to 7.62x25. It's a novelty gun for me and I have far better 9mms for range use. I upgraded to a modern firing pin early on but always had trouble shooting due to the awful trigger on mine.
You did the right thing by not firing it too much. I had one for about a year, probably shot it once a month for a year, call 1000 rounds more or less.
The slide cracked high near the ejection port. One of the militaria collectors at the range I shot at took a look at for me, and told me that he’d had 2 crack in the same way.
I got a replacement slide, but I was a little wary after that - the crack was a little hard to see, I only noticed it when cleaning the weapon after shooting. I don’t know what would have happened if I had kept shooting that day, since I hadn’t seen the crack until I completed shooting. I felt like I needed to check the slide for cracks after each magazine, which took the fun out. I about give it to a collector friend of mine - he wasn’t all that interested, because the serials numbers no longer matched.
I never shot the “hotter” military surplus ammo, I only shot the commercial S&B loads that were supposed to easier on the weapon than some of the surplus ammo.
It looked like it was way overbuilt, but it may not have overbuilt in the right areas, or it happens that my friend and I got lemons.
Mine had a crappy trigger, and on my apparent way improve the trigger was to replace firing pin with one that eliminated a little plunger that was part of the drop safety. I was not too anxious to do that, so I just put a moment firing pin in and lived with the crappy trigger.
Very interesting action, and a fun round to shot, but oveall a bit disappointing. My unsolicited advise is “for collectors only.”
