After the USAF was created as its own uniformed service on September 18, 1947, it went from using Army Regulations to writing and using its own. When it came to drill and ceremonies, the newly created service looked at the Marine Corps and Army drill manuals and chose from what it considered the best from each (most from the MCO). One thing the USAF eventually left out (beginning in approximately the 1970s) was the manual of arms for the rifle. Why? Because the Army and Marine Corps had already accomplished that task and Airmen did not have a daily use for rifles like Soldiers and Marines.
