I think you made a typo. One ounce loads aren’t anywhere close to 1600 FPS. The 3-1/2” BB’s I shoot at late season honkers only come out at 1550FPS.Remington 12 ga. Express loads are 1,330 fps. and most 1 oz. loads @ 1,600 fps. have a relatively low pressure level, depending of course on the specific loads.