Taking a strait razor blade and curving the spine a little to make a mini scraper is a great way to get the finish off of the 1970's era Bears. The finish they used then was extremely hard. The Super Kodiak I refinished took a ton of time to get the finish off as compared to the 1950's Bear recurves. I wished I knew the razor blade trick before spending all the elbow grease time on this Super K. I used wipe on polyurethane for my finishes.
Here's a before and after of my Super K
after with Berger Button hole filed:
Before. Note the yellowed finish: