My local gunsmith just fitted a Bar-Sto barrel in my 9MM CZ. I bought the barrel as semi-drop in, but it was more like a gunsmith fit. Took a lot of hand filing and Dykem to find all of the oversize areas. It is a nice tight fit now. Can't wait for a chance to shoot it. Next will be Cajun Gunworks's hammer and sear then a refinish from Mac in Arizona.