I run a Mini Buzzard with a freak barrel. I have had zero problems with the bolt dragging on the freak inserts (I usually use a 679)
I have heard some users need to put an o ring between the snub and the outside of the barrel threads. This keeps the barrel from screwing in completely and making an artificial bevel.
I would recommend a true freak barrel. I have found barrels milled out for freak inserts don't work as well. The bored out freaks have more wiggle room than the true freak barrels that have O-rings to hold the inserts in place. I find the wiggle room affects accuracy. That is my expirience others may differ.