I have the exact same gun a Remington 700 ADL in 270. I don't think you'll miss anything with a 22" barrel. I've been told that a 270 Ackley Improved, a 270 with a little bit more case volume, can utilize a 24" barrel in fact in a 22" barrel you probably wouldn't see much difference between a 270 Win and a 270 Ackley. I've always believed that you only really need the longer barrels for the real high capcity magnum cartridges. You'll see guys on here with 270s and 30" barrels. Now a 30" barrel will make a difference for sure but 22"-24" don't sweat it. As far as the 130 BT's they are amazing perhaps not the best choice for ultralong range as there are higher BC bullets and energy wise the 150 BT has an advantage at distance. That said my 270 absolutely loves the 130 Nosler BTs.
I shoot handloads using 58gr of H4831 considered "THE" powder for 270s. I would imagine factory ammo would use a very similar powder. All I've done to the gun is glass bed the action and lighten the trigger pull other than that it is stock. These are two very easy steps you can do at home that will make a big improvement if you haven't already.
That's 3 130gr Nosler BTs at 100 yds. in .573" edge to edge, center to center is just under .3" That is the best group I've ever shot and I can't do it all the time but my rifle will do it more often than I can [img]/ubbthreads/images/graemlins/wink.gif[/img]