1. Welcome from Georgia.
Please take a few moments to familiarize yourself with all the sticky posts in the 'New Members' section. Together with the Help Topics in the 'Important Information' or 'FAQ' sub-section, these include 'how tos' such as 'how to' post pictures on the forum.
2. To answer your question, you are not alone. Every new-to-CZ reloader seems to run into this... You'll simply need to improve up your reloading practices to reload ammo for the CZ. The CZ chamber is to SAAMI standards, but it does not have any of the looseness, or chamber reliefs found in Ruger, S&W, or early Glocks.
Furthermore, due to the very short CZ freebore, some American-only bullet
shapes (e.g. hollow point, conical, wad cutter) cannot be tolerated. (I'm not saying these can
never be used. I'm saying that
even more care will be needed.
It's all explained in the "stickies" of the
Ammo & Handloading Section, right here....
https://czfirearms.us/index.php?topic=100352.0Since you currently reload, please begin at:
Physical Details of Cartridge Building.
All questions pertaining to ammo and/or handloading practices should be posted in THAT forum, please.
Right now, I highly suspect 1 or more of these questionable practices...
• Using brass previously shot in OPEN Class competition
• Incorrect
Taper Crimp• Excessive OAL
Hope this helps.