Mosin Nagant Model 91/30
I recommend the Mosin long rifle, the Model 91/30, for any serious target shooting. IMHO the longer barrel is a real advantage, and not just for the longer sight radius. If you think you might get into SERIOUS target shooting, you may wish to spend the $10-$20 premium for a laminated stock, which is more stable than a "regular" wood stock.
The 91/30, for all it's length, isn't a particularly heavy rifle. There is a LOT more gunpowder in the 7.62x54R cartridge than in the 7.62x39. That means the 7.62x54R cartridge will deliver a healthy recoil when fired from a 91/30. I'm "recoil averse", (old fart with arthritus in right shoulder joint) so I use a recoil pad. (Cabela's has one with velcro for easy on/off - I also use it on my K31s, 7.5x55 Swede, 8mm Mausers and M1 Garand.)
The 91/30 will be the cheapest of the three rifles in initial cost and in ammunition supply. I checked ammo prices today and 7.62x39 is more than double the cost of 7.62x54R at my usual sources.