On the older CZ 527 rifles with fixed sights the barrel has a buttress where the rear sight dovetail is cut. This part of the barrel is slightly wider than the rest of the barrel. The newer 527 rifles use a screw on rear sight with no need for the barrel buttress. The older stock has a relief cut where the rear sight sits. I dont know if the newer barrel has the same overall profile as the older barrels but if they do have the same profiles cutting the barrel buttress relief wouldn't be all that hard. The relief is only about 5/8 inch long and less than an 1/8 inch wide on each side. Its not unusual to have to relive these cuts slightly when bedding the older barreled actions. Just careful use of a scraper. Good luck in your quest.
Thanks much David. That makes sense I know exactly what you are talking about, in fact I like that detail in the barrel and am glad I have the older version. I would have no problem inletting the barrel into the stock w/o that relief, I've done my share of inletting in my time. But, as you said, the newer version of the barrel would, hopefully, have the same profile/taper as the older models.
Thanks again !