Do a history search and you WILL find that JMB did not invent the 1911 in 45 Automatic initially. He was asked to provide a gun that met the governments criteria of a 45 caliber requirement. He converted his invention to handle the 45 Automatic round. The original round was of 38 caliber which is closer to the 9MM. Don't get me wrong, I'm a 1911 lover as well with them in 45 and 10MM variety. I have Glocks too.