The answer to the basic question is- Yes it can be done ( the rim recess can likely be cut into the existing extractor, after removing the plunger). Several people questioned the need to do this though. If you want a 30R Blazer and have a tip up in 30-06, of a make that is not available in 30R Blazer, it makes sense to make the conversion rather than pay the several thousand dollars for a rifle available in 30R Blazer. This is especially so if you already have several other 30-06s.This assumes a single barrel, to avoid "regulating" problems.
Mike
