I've decided to take an NRA Pistol Instructor class to improve my own shooting (I doubt I will do any formal training with the certificate). I learned that there is a prerequisite shooting skill test of putting at least 16 of 20 shots into a 6" area of an 8" target at 15 yards. The schools teaching the class emphasize that there is no calibre restriction on passing that test (HINT, HINT). After a practice day at the range with my .45 ACP 1911, Model 66 (shooting .38sp), M&P 9m (my EDC), Hi Standard model 103 (.22lr), and Heritage Rough Rider, I will be using the Rough Rider for my actual test. So, my question for others.. if you have gone through this process, what gun did you use?