CZ 527 Notch on rear mount changed from squared to rounded

[sirgilligan]

I picked up another CZ 527. This new one is the Carbine, my other one is a Varmint. I had purchased a picatinny rail from CZ when I got the Varmint several years ago. I put it on and took it off and mounted a scope using CZ rings. I thought I might put a red dot on the carbine. I tried putting the rail on it and it wouldn't go. The old CZ has a squared female receiver notch and the new one has a rounded end receiver notch. The rail has a squared male receiver notch. It would not fit.

When did this change? Why would it change?

Older Rifle:


Just took a photo of the new rifle:

[sirgilligan]

Anyone else have a CZ 527 with the rounded notch? Does anyone have a new CZ 527 with the square notch?

[eastman]

I don't have a 527 (yet), but the rounded notch is going to be a lot simpler to mill.

[david s]

I have a "C" prefix from 2017 that I'm 90% sure has the earlier square cut, today I have a 2008 apart with a rounded cut so I'm certain it's after 2008. The cut switch is a fairly recent change you might try asking CZ-USA for a definite date/serial number.