Mikey; You could pump up the 7,62x25 round in your rifle too, close to 1,900fps with no worries about hurting it. I'm not sure how accurate the faster rounds would be. It has potential and options.
I've been debating picking up another Spanish 1916 308 mauser to pick between the two i have which one is the worse condition one meaning that "looks" worse it has to have a good bore too, to put a 7,62x39 chamber adapter in to shoot the cheaper 7,62x39 ammo but it opens up a whole new world too with the 154gr wolf soft point ammo and the hotter heavier stuff that is being manufactured too. It just sounds like another toy to play with and it has a bunch of options. I guess the feeding has to be reworked so the magazine will work correctly too. I just don't think a single shot will cut the mustard if you using it for up to deer sized game. I just purchased some of the wolf 154gr 7,62x54 ammo to try out in my sks on my next trip to the 100yd range to see how good it is. Since one of my sks's has been an accurate shooter I'll use that one to test the 154gr ammo. I wouldn't mind a sporterized spanish 1916 7,62x39 mauser with a scope too, it sounds doable. I think if we cut and block the magazine forward just enough to fit the 7,62x39 round it will work and feed properly too. Much like shooting 9mm in a 7,62x25 pistol they block the mag forward for the shorter round. I'm not sure why they didn't do that on the test rifle. And the cost your way under $200 for a total project gun. I think it will be a worthy tac driver too. Its just another way to have a bolt action 7,62x39. BigBill