[Unclenick]

Actually, even the Savage will stretch the chamber, since the nut works against the receiver threads to tension it. Chamber draw on the order of one to two thousandths per inch of chamber length isn't an uncommon range to encounter in many rifles. It's just that with the Savage, if you don't like how the headspace ends up you can easily loosen the nut and rotate the barrel and re-tighten until you get it where you want it. On conventional receivers there's no such easy tweak. Assuming you stick to the factory barrel torque specification, on conventional barrels how deeply you cut the chamber is the critical determinant of your final headspace, whereas the Savage chamber cut could err a few thousandths and you'd simply adjust it out when you set up the barrel.