I thought about posting this question in the gunsmithing section but don't see much pistolsmith advise there so I'll try here:



In the foreground is my newest C&R purchase, another CZ52. Same year date (1953) and factory (rid) as the one with the replacement grips in 7.62x25 Tok, but it has been factory refurbished with a 9x19 barrel...it is even serial numbered to the frame and slide.

I bought it online from JoeSalter.com. I have never received ANY weapon in this condition...bone dry, not a smidge of oil or grease anywhere. It was almost like it was dunked in carburetor cleaner then left to air dry, although it was probably aerosol GunScrubber. But not a speck of rust, thankfully.

So I swabbed every metal part with Breakfree CLP and greased the slide rails with Shooter's Choice Hightech grease. I brushed and patched the chamber and bore, then off to the backyard bullet trap to try it out. I had read accounts of these 9mm barrels shooting low because the military fixed sights were adjusted for the trajectory of the lighter and faster 7.62x25 cartridge. I didn't find that to be true from ~10 yards.

At least one failure-to-feed occurred with 5 different jacketed loads (4 roundnose and one hollowpoint) and my one cast lead reload...the one that functions all my other military 9mm's. The cartridge seems to clear the magazine's feed lips, then 'free jumps' towards the chamber where it is cocked and prevents the slide from locking up.



I switched magazines with the other CZ52 but to no avail. So I spread the lips some...no change. And pinched them in a little...still no change. I tried loading only 4 or 5 rounds instead of the max 8+1...no change. This is starting to piss me off! I've never had any pistol be so finicky about ammo.

I'm using a two hand grip so no limp-wristing.

I'll try polishing the feed ramp to see if that helps any.

I had hoped this to be my car carry gun, so it needs to function 100% of the time with factory hollowpoint ammo. But I'll be damned if I'll throw $100 bills out the window experimenting with every self defense factory load available to see which one this gun likes.

Any suggestions on things to try that I've overlooked? Perhaps the extractor needs smoothing?

my 2 cents:

check the extractor on both. Are they the same?

Is the rim on the 9mm the same thickness as the 7.62?

If you can get a spare extractor, releave the bottom hook.

exagerated - like this |\ instead of this ||.

Check to make sure the chamber and throat is proper size. 52 are made handle stiff loads standard US 9mm loads might be on the light side. I would use loads in the plus p range. If the side isn't going all the way back it well not have the power to strip it from the mag and shove it into the chamber.

Check the extractor as rich says it might not be allowing the rim to slip up under neath as needed.

I polished the feed ramp and chamber which made no change. I'm almost positive the problem lies with the extractor, but I don't know the proper way to relieve it.

And since no one spoon fed me the correct way to relieve the hook portion of the extractor to match the 9mm cartridge, I spent $20 on one made especially for the 9mm CZ52. Here is a pic of the original on the left. Note how much of the new one's hook has been ground off.



It has worked perfectly with ball ammo, not one single FTF. I can not say the same for hollowpoint self-defense ammo. Hornady 115gr is the worst, probably because it is the shortest. Remington Golden Sabre is the best but still jams about once every magazine full.

I'll work up some reloads to see what it likes.

Doesn't look to be ground at all how I imagined it.