I understand how guns work, my friend, I’m no spring chicken here My problem is now that the new +3 base pads are installed, the slide does not hold open on the empty mag. Everything else is the same. All put back together correctly. I’m thinking maybe it needs a longer spring- more tension on the follower. It’s going from 7 rounds to 10 rounds with the same spring. I have similar extensions on a few of my other CZ’s that work perfectly with the same mag spring. Also, with the extension removed and the mag is back in its original configuration, the slide holds open every time.