I hunt with three difference .270's and have a great deal of respect for the caliber as a white tail deer cartridge. Each of my rifles has a differenct barrel length but all are Remington 700's. They are:
1. regular 700 BDL blue barrel, 22 inches long.
2. regular 700 BDL, stainless, 24 inch barrel,
3. Sendero heavy barrel, 26 inchs.
With these three rifles, and the same loads, I've found the .270 to have the widest velocity spread of any caliber I reload for. Using 130 gr bullet and H1000 with the same powder charge there is and average 180 feet per second difference between the shortest and longest barrel.
Using 150 gr bullets and H1000 it is in the neigborhood of 140 ft per second. Using 130 gr bullets and H4831 the difference is about the same but the shorter barrel seems to hold its speed better. I use max loads of slow powder and I think the extra 4 inches in barrel length really helps out in letting all the powder burn. However, three guns don't make a universal rule for everbody.