Kimber Sapphire 1911 doesn’t like FMJ practice rounds

We then compared the rounds’ overall lengths as well as profiles to see what the differences were. We did not have time to chrono the rounds to see if powder charge had anything to do with it, but we plan to as the Sapphire has a 16 lb recoil spring in it which could make a lighter load round not allow the weapon to cycle properly.
We came to the conclusion that while overall length and shape of the tip of the rounds may not be the only reason for the misfeeds, it clearly was a contributing factor. Check out the video below: