RE: Favorite Russian Boar Caliber
Have used mainly .44 Magnum, 240 grain bullet, on boars of the size you mention. Rossi Puma Stainless Steel, 16 inch barrel is the gun.
Has worked well for me, but the shots have all been close i.e. less than 50 yards, and mainly 10-20 yards.
I like the short gun when hunting pigs, as I usually hunt in very thick scrub, and it doesn' t get tangled up all the time when it' s slung on your back. Also it is a very light weight.
Would consider using a handgun if they were legal for hunting down here. Unfortunately they are not.
Your gun choice will depend on the type of hunting style; stalk, stand, dogs etc.
Those big boars have a very thick shoulder sheild that takes a lot of penetrating.