I think it depends on what speed the manufacturer designed the given bullet to be effective, intended use, and validation on your part, I don't know if your considering the hornady interlocks, Speer hot cors btsp bullets "soft points" or not, psp by name is pointed soft point, but I've had good luck out to a 1000 on steel, which is about as far as I've gotten to so far, and I'm not quite sure what you mean by deterioration, are you referring to velocity or the bullet itself ... I have found bullets at long distances pretty much as they left the barrel as they had a soft landing in loose dirt