I have had at one time or another three different barrels in .257 Ackley, and it is a heck of a good round. Mule Deer has used the .257 Bob and great deal and loves it. He has also used the Ackley version and did find good velocity gains, but has basically decided the standard version is all you need. I have two 6.5 Swede's, and it has quickly become one of my favorites. In both barrels, one 26" and the other 22", these gave velocities within 25 fps of my 6.5x284, which also had a 26" bbl. Granted the 6.5-284 may have been a "slow" barrel, but the Swede is awesome. In my MRC 1999 it regularly shoots in the high 2's and low 3's. Having used both, I would go Swede all the way.
