I tried American 8mm ammo in my Yugo 48 and was surprised to see that the sights were on for 100 yards. This would not be true with ammo loaded to European specs. I suspect that the American companies loaded their ammo light, so that shooters would be able to use their rifles without resighting them. As to complaints of lack of power, not everything needs to be a .323 Belted Brontoslayer to work on whitetails. Even if you accept the premise that American 8mm is no better than a .32 Winchester, the .32 has killed a lot of deer over the years. Of course, it was shot mostly by guys who knew deer hunting, but did not read magazines to find out they were underpowered.
Use the barleycorn front sight the same way you would a Patridge sight, even with the top of the rear sight and centered, and you should do fine. Do I need to say, shoot the rifle on paper before you take it to the field? Shoot no further than you can keep all shots on a nine-inch paper plate.
Good hunting to you!