I called
SSK Industries last week about having my Marlin 336CS 35 Rem. rechambered to 356 Win. The lady I talked to was really nice. She said they do this conversion from time to time and its not a big deal. In addition to reaming the chamber they also have to open up the bolt face. The 35 Rem. has a smaller diameter bolt face then the 356 Win. You could probably use a bolt assembly from a 30-30 Win. since the 30-30 and the 356 have the same size rim.
If you were to have a 30-30 Win. rechambered to a 307 Win. the only thing you have to have done is have the chamber reamed. The bolt face doesn't have to be opened up because the 30-30 Win. and the 307 Win. (and the 356 Win.) have the same rim diameter. Its one less thing to worry about. Plus you can find 30-30 Wins. all over the place!
I think a
336Y or a
336SS in 307 Win. would be a great woods rifle. I could also say the same thing about a 336CS in 356 Win., especially if it's going to be more of a black bear, wild boar and then a deer rifle!
*Here* is Winchester's factory loads for the 307 Win. and 356 Win. The 307 Win. has 20 grains less bullet weight and .050 of an inch less bullet diameter. I don't think there is a deer, black bear or wild boar out there that could tell the difference! Good luck!!! :grin: