Ruger's arms are squeeze bores. They are shoving a .311" bullet down a .308" barrel. Not good for accuracy. That's the main problem with NEF bring out one of these. All their .30 cal barrels are designed for rounds with a bullet diamter of .308" (.30-30, .30-06, .308, etc). 7.62x39, 7.62x54R, and .303 British all use .311" bullets, and hence would require they tool up for a completely differnt bore diameter. That just makes it more expensive for them.
The ammo is cheap, but I eventually just decided to get an SKS. With the Yugo version you even get a gas shut-off valve which turns off semi-auto fire, and allows you to work the bolt manuall between each shot.