it is strictly the diameter of the bullet not the whole shell size. although they are most times small ones.
yet an ar-15, which is the most feared by many, used by the military in vietnam. is merely a 22 diameter bullet as well. just tiny bit heavier in some cases and much more powder.
yet an ar-15, which is the most feared by many, used by the military in vietnam. is merely a 22 diameter bullet as well. just tiny bit heavier in some cases and much more powder.