I wouldn't worry at all about using "+P" or other warm loads for defensive use, and the occasional familiarity check. Just use standard loads for range practice, and you will be fine. I use a Wolff 18.5lb spring for both Double Tap 230gr Gold Dot defensive loads (not technically +P, but warm at 1010fps), and for Federal American Eagle 230gr FMJ's, and the weapon cycles perfectly either way. I will say, though, that I change the recoil spring about every 2000 rounds, just to be sure.