Hi, being from the States my perspective might be slightly different so please take that into consideration, here acquiring more rifles is more a matter of budget. If you are only allocated so many rifles I would be aware that there is no “normal” way to mount optics to a k31 and it might be more fuss than it’s worth. As moeggesit mentioned as well make sure it’s a new style action. They eject brass straight up so a conventionally mounted over the receiver scope won’t work. Your options are an offset scope mount (they make clamp ons that work well) or a long eye relief pistol style scope mounted in a “scout” configuration off of the rear sight base. Of the two options the offset is probably best if you can adapt to the ergonomics because scout/pistol scopes have very poor field of view and typically no way to adjust parallax or dial for dope easily.
That being said for issued rifles they are very nice, exceptionally well made, good bores (gp11 was non corrosive) and fantastic triggers. I have owned two and still own one of them.
As for the cartridge as others have said they are inbetween a 308 and 3006 power wise, ample for taking elk here stateside. I am unsure of the exact case volume but it is bigger than 308. Another note, if I recall correctly the bores are actually .307 but reloading is done with .308 bullets (I never loaded for mine). I also recall that the Lee dies were for the older case dimensions, not the updated chambering for GP11, with Redding dies being the best for accuracy (unsure of RCBS). Another note that the GP11 was an early adopter of secant ogives. Finding a bullet combo that matches the performance of GP11 might take some tinkering. Outside of surplus GP11 I exclusively used factory loaded PPU 174gr softpoints and killed two whitetails with mine configured scout style with a Nikon 2-7 pistol scope. With GP11 I found the rifles shot around 2moa maybe a bit better, mind you this is not bedded and not free floated with full length wood hand guards shooting surplus ammo so that’s pretty good. Another note they can be a bit heavy I think mine weighs in over 11lbs all kitted out.
I will try to attach a couple photos but I am new so not sure if it will work. Mature doe shot around 300m and fawn around 200m. Sorry for rambling a bit.
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