DBoston,
Did exactly that with a very accurate .270 Weatherby Magnum I had for a while. After working up a load with 130 Ballistic Tips, which averaged three in around 1/2" at 100 yards, I switched to the 130 E-Tip with the same load--and they did not shoot nearly as well.
But they did after some experimentation with seating depths. Turned out the E-Tip would also group three in 1/2"--but they had to be seated .1" deeper.
