CZ-50 malfunction

[beemer]

I have had this CZ-50 for several years, it's in nice shape and shoots well. The pistol will fire and run fine if the first shot is fired single action. It will not fire double action, it doesn't even dent the primer. It seems the hammer is catching on something. Anyone with ideas or experience with this.

Thanks
Dave

[MtGun44]

Does this model have a hammer block safety and decocker? If so, I would suspect the
hammer block is somehow not working correctly.

[beemer]

I finally took it apart, the safety tumbler has a notch that rotates to block and unblock the hammer. I think I have ruled that out. The sear is in bad shape, I will have to check that out.

Thanks for the input.

Dave

[Just4HavnFunGuns]

Sears, sear pin and spring are available at Apex Guns. One of the differences between cz 50 and 70 is the hammer bolt. The cz 50 bolt has a notch cut in it that the little tab on trigger bar rides in. Easy way to tell which hammer bolt is installed is the cz 50 had opposite nut side a bolt with no screw slot. cz 70s had a screw slot in hammer bolt, but no slot in side of bolt. Wideners recently had these as gunsmith specials for $120. cz 70s for $110. I picked up 4 50s and have managed to get 3 of them working so far but with the condition you are describing. Ready for a range trip on one that I have been working on to see If I solve the problem. One little tip is if you can get a hold of a 4-5" x 1/4" soft brass rod and with the gun pointed up pull the trigger in both S/A and D/A. The brass rod should jump an equal distance out the barrel. Good way to check your decocker also as the rod should not move.

[beemer]

I will check out Apex. Have you had any problems with the firing pin block ? If you solve the problem let please me know.

I see this your first post. Welcome to the fun house !

Dave

[Just4HavnFunGuns]

No problems with the block. I did disassemble the firing pin and block/& block spring from the slide, and soaked the guns in a can of mineral spirits for 24 hours. Then into a hot ultra sonic bath for 100 minute. sprayed everything with brake cleaner and reassembled. I used drill bits and small files to true up the firing pin and block holes, hand turning.
The slides are made of a softer metal, the back edge under firing pin hole where they hit the hammer on blow back were starting to peen over. Just filed and rounded it over slightly. First 3 I took apart all had the hammer bar spring in the top pin where hammer bar pivoted, and all 3 springs were slightly different, one looked like it came out of some other gun as the coil part was larger. The fourth had the hammer spring in the trigger pivot pin! I checked my cz 70, and that was where that one was also.
I am almost positive it should have a stronger trigger spring. One that would hold the bar up against the hammer a spit second longer allowing it to cock further back in D/A. I will let you know if I come up with anything. They are kind of fun to play with and learn what make's them work.

[Just4HavnFunGuns]

140326This is my cz/vz 70 collection