The CZ-527 is the small bolt face "mini Mauser" in their rifle line. I want to build a .17 Fireball on a yet to be purchased rifle. My question is how much barrel can I hang on the front of this action? If you have one or experience rebarreling, what s the front ring diameter? I want a heavy barrel to resist heating when prairie dog shooting and allow me to keep my sight picture when fired. My heaviest barrel is a "NBRSA Heavy Varmint" contour which is .920 at the Muzzle and 1.23 at the breech. Can I use this contour or would a Douglas 1.20 contour breech be necessary because of the front ring?