You need a manual. Contact Winchester or find a gunsmith and ask for help.
The Model 77 Winchester will fire either long or long rifle cartridges. It is not chambered to fire short .22s cartridges.
don't take down a Winchester model 52, the way they bedded the rifle was a mystery. It may never shoot the same if you take it apart.
Best left to a factory trained gunsmith
You should be able to find a assembly-disassembly guide for your Winchester model 37 on E-bay.If not you may to need to visit a qualified gunsmith.
You need a copy of the owner's manual for your rifle- trust me- parts of the bolt are tricky. You can get a copy for free from Winchester is you are in the US. The link below will take you to their order form on their website.
hit it with a hammer
You can get the manual from this page with some basic info. http://www.winchesterguns.com/services/index.asp
take it to a gunsmith
Take it to a gunsmith for exact measurement
All Winchester model 12's are take-down designs. Winchester made a model 25 which is solid frame and very similar to the model 12.
Best to ask a gunsmith for help