If it is a model 98 or commercial sporter action than it is going to be a Large ring. It being a 30-06 is giving me the gut feeling that it is a large ring.
The small rings are the Model 96,95,94, The sweedish and spanish mausers usually made in 6.5x55 and 7x57. It is pretty rare to see gunsmiths rechamber any of these in 30-06.
What marking are on the rifle? Place of manufacture?