I shoot a 154 grain factory soft point in my SKS. The biggest bullet in .30-30 is a 170 flat point and, personally, I've never used more'n a 150 in the .30-30 and have killed a half dozen deer with it, one out of a rifle and one out of a 12" pistol at 90 yards, the rest at shorter ranges out of the Contender pistol.. The 150 Nosler BT load I use in .30-30 from the pistol (no longer own the rifle) leaves a 12" barrel at 2050 fps. The 154 grain Wolf load fires 2200 fps out of my 20" SKS. You tell ME which carries more velocity/energy.
The difference is negligible even if the .30-30 is fired from a rifle. I didn't have a Chronograph when I owned that rifle, but the manuals all stated 2400 fps, but when I finally got a chronograph, I measured factory 150 RN out of a friend's pre-64 M94 Winchester at just under 2200 fps.
I mean, it ain't like the .30-30 can break 3000 fps AND a factory 154 soft point has a better BC than a 150 flat point and will have a much better effective range. I consider the 7.62x39 as a semi-auto .30-30. The numbers back me up. Both will kill deer quite dead with the right bullet. In fact, I think if I hadn't stumbled on this excellent 154 Wolf, I'd probably be handloading flat or RN .30-30 bullets in the x39. But, there are other alternatives to the handloader now days in .311". Accuracy is adequate to 200 yards. Even a .308" bullet will generally group 6" at 200 yards. The 154s are slightly more accurate and will group 5" at 200 yards. A deer's kill zone on the shoulder is around 12", so if you can keep 'em on an 8" paper plate, that'll do. No, it's not as accurate as my 1/2 MOA .257 Roberts or my 3/4 MOA .308 Winchester, but in the woods, it'll get the job done. And the gun is heavy as I've described, so it's quite soft on a tender shoulder.
The accuracy of the x39 is extremely good out of a strong bolt action rifle. I'm convinced it's an inherently accurate round. The SKS doesn't do it justice far as accuracy goes. A bolt gun will be a lot lighter and felt recoil will be rougher, though, if you have issues with that. No worse than a 6 lb .30-30, though, and in fact a little lighter I'd imagine without running the numbers. .30-30 holds a little more 3031 than the x39 holds 4198.