gzig5, thanks for your explanation and for the cite to RimfireCentral as well. I have taken apart more than one 46+letter and you are right - it sometimes takes a good bit penetrating fluid and maybe gentle heat.
BUT - the bolt design of the older 46 (no letter suffix) is different in that the section to the rear of the bolt handle is a one piece tube - no seam or break - and it seems as though the knob on the very back end must unscrew in some way. In this case, it looks like maybe someone peened the tip to keep it from unscrewing. I would go to work on that aspect if I knew for certain about that design.
Any such insight on this model bolt will be appreciated.
