RAS,I went that route trying to mount a NIckelMarburg on a Sako.I even tried SAKO 26mm rings and they felt too tight as well.I didn't want to damage the tube so I sold them off.I ended up with Burris Signature rings.I opened them(inserts) up a little with a dremel and they worked fine.A little bit of a PIA doing a little at a time but got a good fit.
GL
