My opinion only: fun gun for short range plinking and hunting not to exceed deer size animals. Effective range of .30-30 in lever action rifle is 100 yards or less and accuracy is so-so with open sights. Combination is NOT as effective or accurate as a typical bolt action rifle in .308, .270 or other high power center fire caliber. YMMV
The 30-30 is popular in areas where long-range shots are not the norm, and is frequently described as a "brush gun." I've heard of ~200 yard shots, but those seem to be about the maximum. Excessive bullet drop past 100 yards seems to be most of the issue with accuracy (and lethality).
I've heard the claim made that the 30-30 cartridge has put more venison on kitchen tables than any other rifle cartridge and that its popularity has only recently been eclipsed by the availability of cheap SKS rifles and steel-cased 7.62x39, but I don't have any references to back up that claim. The cartridge has certainly fallen by the wayside of the gun-owning public's imagination with newer, flatter-shooting cartridges that don't have the handicap of being derived from a low-pressure black powder round with the additional ding of flat-nose bullets for use in tube magazines.
I have a 30-30 and use hornadys new leverevolution ammo. Check out hornadys website it has alot of info on this new line of 30-30. Makes a brush gun very reliable at a hundred yards. I have shot a couple of hogs with mine inside of hundred yards and just dropped them in their tracks. They say this ammo is good out to 300 yards but I dont have a need for that so I havent tried it.
The real question is how far can you routinely hit a paper plate with one from? If I am sitting, I am not too worried about missing it out to say 150 to 200 yrds with my peep sighted pre-64 Win 94. If I were to get a Texas sized buck in my sights in under 200 yrds, I think it would do the job just fine.
The 30/30 is not a "sexy" round, it is more a get the job done if you do your part. At longer ranges it is not as forgiving of a bad shot like say a 300 win mag would be one a hill country deer.
Here is what my 30/30 did at 100 yrds off the bench.
I have a winchester 94 20 inch barrel with the Burris 2-7x32 pistol scope. I shoot the Hornady Leverevolution rounds out of it now. I can consistantly make 1/2-3/4moa shots at 100 yards with this rifle. And that is on par with any bolt rifle on the market. When it comes to lock up, and rigidity, lever action and bolt action are at the same level.
Previous loads of 30-30 rounds are very flat on the tip making the round drop faster, and be slightly inaccurate. The lever evolution round is leaps and bounds better than regular 30-30 rounds. You can make cold bore first shot hits with this round to 500 meters with proper sight adjustments. If you want good shots to 300 yards, just sight your rifle in to shoot 3 inches high at 100. You will shoot 0.2 inches high at 200, and 12 inches low at 300. Just compensate on the fly.
I have some rediculous experience with this rifle, and have taken large bucks out to 300 yards. It just takes a steady hand, and knowing how your weapon shoots.