Yes, you are correct. It was either captured by the Finns during WW2 or purchased from Germany during WW2. Since it is a 1927 model we can rule out anything from WW1. But who knows the original stock was most likely damaged and had to be replaced. The Finns kept any and all spare parts that were...
Actually, you have an M91 dragoon in a Finnish made pot belly stock. The barrel length is around 3” shorter than an M91 infantry rifle. M91 infantry rifles were made until 1926 by the Soviets. M91 dragoon rifles were made until 1932. They were phased out and/or updated to M91/30 specs in the...
The bands on a M91 act as a clamp/screw setup. If I'm thinking correctly you need to turn the screw clockwise until it stops. Then the band will "un-clamp". Or vice versa.
If you can't get it to budge I'd leave it be. Just be gentle with it you have a valuable piece of history.
Hope this helps.