This morning I took my Polish CHRONO to the East Devon ground to test with a members CB625.
Same as before fitted the CB625 to rifles and at same time through the Polish one.
The results were virtually identical as yesterday's test. My CB625 and the other one read the same errors one from the other +- 3.
So I'm happy to say the CB625 barrel fitting chronographs are very good and the fitting distance is virtually the same on all rifles.