I can't speak to the Winchester shells, but years ago I got some Eley Hawk low-noise, low recoil, sub-sonic loads and they shot fine out of the right barrel of the 4-weight Ansley H. Fox B-grade I was using, but the left barrel shot waaayyyy off the mark. Use my 1200 fps, 7/8 ounce, 6300 psi Remington STS reloads and the gun shoots right on with both barrels. A single example, but that was my experience. Everything I load, I load to 1200 fps, it makes my mind happy.