I am new to IDPA and have been using my S&W 945 in CDP. At the last match another shooter told me that my gun was not legal in IDPA. He said my mag release was oversized and to long. I checked the rules and the only measurement I could find was .2 inches tall no measurements as to diameter of button. This gun is as it came from Smith. The button is larger than the shaft of the release but nowhere as large as the button on my old Behlert open gun. I asked o. Idpa form with no real clear answer. I called the MD at the local matches he didn't realize it was not a true 1911.