Grouper,
Yes, you are correct about the barrel length. In fact, all non-magnum Tikkas have 22 1/2" (or so) barrels, and magnums have 24 1/2" (or so) barrels.
Yes, you are also loosing a bit of velocity with a 1 1/2" inch shorter barrel, but you are really not loosing anything. Loose "full potential?" Nah. Many gun makers make the 270 in 22" barrels, or even shorter. Granted, they too loose some velocity, but you won't notice the difference.
Tikkas are accurate as heck. I'd rather loose about 50 fps and gain excellent accuracy any day.
Personally, I do like barrels of at least 24 inches. That notwithstanding, my .270 is a Browning Stainless Stalker (A-Bolt I) with the 22" barrel. I seriously doubt if I, or the deer, notice any difference with a 2" shorter barrel.