To put the 7.62X39mm into perspective, think of it as a shortened, rimless .30/30. It will fire bullets of the same weight as the .30/30 at very similar velocities using comparable powder charges. Out to 200 yards, it is just as deadly as a .30/30 and is good for the same sort of game. I believe your thinking about the 6.8 SPC is correct, but I do not think it would be any better for deer and coyotes than the 7.62X39mm. The Russian round is available anywhere in the world, and some of the ammo is very cheap even today. In a rifle like the CZ 527, the 7.62X39mm is as accurate as any cartridge, if good bullets are used. One thing about the 6.8 SPC is that there aren't just tons of rifles made for it, and it is NOT a popular chambering, yet. I don't know if it will ever be popular, or even if it will survive.

I have had terrible accuracy problemsusing the Mini-30 and the Mini-14. I have heard rumors that Ruger has finally figured out how to make them so they are reasonably accurate. I don't know if this is true, but I will never buy another one until I see proof that the accuracy problems with them have been fixed. However, the CZ 527 is something else again!