CZ 52

The CZ-52 is NOT made by the same company that makes the CZ-75 series of pistols, but it's still a high quality piece. It's a single action only with a decocker. There is no external slide lock, but you can bump the bar up to engage it with a bit of practice.

It's famous for using a roller bearing locking system similar to some Heckler and Koch rifles. The system works quite well, although there were some issues with high round count rollers going flat. There was a company making hardened rollers in addition to repalcement firing pins. Factory firing pins were known to break in mid round count area. The replacement pins also lowered and smoothed trigger pull, but some models disengaged the decocker function.

Wolff gunsprings has recoil springs.

Harrington Products has the firing pins and rollers.
http://www.harringtonproducts.com/firing-pins/

The original Makarov.com website has a page in info about the CZ-52.
http://www.makarov.com/cz52/index.html

As to supply, check the surplus importers. Most will sell to you thru a local FFL transfer. It runs in batches however, and a quick check doesn't show any of my usual folks having them in stock presently.

I completely agree that different lots of foreign military surplus 7.62x25mm can be loaded to differing pressure levels. And it is Berdan primed, and very corrosive if not properly cleaned for. Here's some chrono data I've collected from my CZ52:

Fiocchi factory 88gr 30 Mauser vel=1330 fps; OAL=1.350" (this case length is too long for CZ52 as neck impringes on throat, however pressure seems mild. If reloading "hot", then cases need to be trimmed)

Czech military surplus ball w/ 85gr FMJ-RN vel=1534; OAL=1.370"

Norinco military surplus ball vel=1488; OAL=1.370"; case length=.970"

Handload: Hornady 85gr HP-XTP (32 Mag bullet sized .308"), CCI500, AA#7 10.0gr; Fiocchi cases trimmed to .970"; OAL=1.244" (to cannelure); crimped for safety; vel=1535 fps; good accuracy; feeds reliably; I consider a maximum load

If you choose to use .223 cases to form brass, 2 cautions are worth mentioning. First, the case heads are too small for the chamber, so the once fired cases will bulge a bit, and can rupture with hot loads. Second, the head and case walls are thicker, so internal powder capacity is reduced. Now that factory brass is so readily available, it's probably not worth the trouble to form cases. I used to form cases from some 9mm Magnum brass that I found at a gun show. That stuff fits the chamber very well, and is very strong brass.

I also have a Thompson Center Contender barrel in .30 Mauser, and velocities really increase with that.