After much hair pulling my 98 Mauser is shooting fine. Actualy it fired great from the start. It just did not feed at all. I worked for some time to get the action to put the round in the chamber. The gun smith called to say it was ready. I asked what he did. He said he polished the throat. I need to ask, how this is done.
Thanks

I think he's referring to/calling the feed ramp the throat. The throat is the area between the actual chamber and the beginning of the rifling, and has nothing to do with feeding.

I've also found the best way to get a M98 to handle a 243, 260 etc is to put a spacer in the rear of the box moving the loaded round forward.

Find a new gunsmith if he told you that, regardless of what he meant. 308 based ammo sometimes does not feed perfectly from Mausers, whose feed rails are optimized for a more tapered case; the 8x57 Mauser. When they were converted to 308 buy the Israelis, they used a spacer at the rear of the mag which helps.