There is more to barrel length than velocity. Balance and muzzle blast are an element. The 06 has loads in a wide variety of weights. If one was dedicated to shooting heavier loads, you could go to a 20" barrel and not lose much statistically. But it would handle very differently. For some, any velocity gain is a big deal. In fact, with the very wide variety of .30 cartridges on the market, I think it is a very big deal in the US. Anyway, heft a few things to get an idea what suits you. I handled a Winchester 1885 High Wall in 325 WSM this weekend. Alot to like there. 28" barrel. Balanced real good to my feel. (Lets see. Do I need a 325 wsm?)