I think I've found a solution to stop people from doing this. When you are a machine gunner (with a dp-28/mg-34) you run around with the gun barrel pointing downwards, and can only hip fire when you press the aim button. Well, why can't they do this with sub machine guns too?
You would still be able to run around while hip firing (but not sprint), while mg-gunners will only be able to walk while doing this. And, to stop people going into this mode all the time, it should take up a bit more stamina than just letting your gun rest (you are holding it up and keeping it level).
A good button for this would be the "f" button for sub machine gunners. I don't know about riflemen tho, maybe just leave them as they are?
You would still be able to run around while hip firing (but not sprint), while mg-gunners will only be able to walk while doing this. And, to stop people going into this mode all the time, it should take up a bit more stamina than just letting your gun rest (you are holding it up and keeping it level).
A good button for this would be the "f" button for sub machine gunners. I don't know about riflemen tho, maybe just leave them as they are?