the 30 cal is inhearantly the most accurate cartridge out there
Duh, "30 cal" is a crude name for a bullet/bore diameter. A "30 cal" "cartridge" could be as small as a .30 M-1 Carbine and as large as a .300 Weatherby Magnum (or even larger wildcats). Over this range of cartridges (and rifles chambered for them) there is an enormous range of power and recoil. NO BULLET DIAMETER is inherently more accurate than others. Accuracy is a function of many variables and the strongest variable is the quality, i.e., price, of the rifle. A $15,000 bench rest rifle is more accurate than a factory production rifle regardless of the bullet diameter, and a 6mm PPC is more accurate than virtually all other centerfire cartridges.