Fab Defense magazines

[DT741]

My CSA VZ58 Compact arrived today. Everything I had to install on it fits EXCEPT my Fab Defense "ultimag" magazines.

They fit perfectly in the 858 but wont clip properly in the CSA.

Anyone experienced this before ? I looked at the magwell on both rifle and where the CZ858 has a vertical notch below the front lip horizontal notch and the CSA lacks this vertical notch. It could be the issue. Magazine are a hair short of being fully inserted.

Metal magazines (surplus, CSA and KCI) all fit in.

 

[DT741]

Solved the problem:

It was the vertical notch on the magazine that was pushing against the receiver. CZ858 has that notch in the receiver but my CSA VZ58 doesnt have it. Filed the notches on my ultimags, easy to insert and no problems feeding ammo