I had a weird instance last year with a .45 and a Wilson magazine.
It was a 47D mag and would constantly malfunction. One of the dirty little tricks it liked to play, was tossing live rounds out on the ground.
I think this was a combination of the magazine, and the unknown but extra power recoil spring. A switch over to a Metalform magazine solved the round tossing problem, but produced another one. The gun would not lock back after the last round was fired.
I don't think the slide was making it fully to the rear.
A live fire function test with my Gold Cup's hardball spring solved all issues, though it wasn't the Gold Cup that was messing up. I just used the extra spring.
I installed a new variable power recoil spring.
For what it's worth this gun I am talking about is the High Standard Camp Perry model I have written about here before. The one that had taken to dropping to half cock when the slide was released.
An enlightened zeal for the energy and efficiency of government will be stigmatized as the offspring of a temper fond of despotic power and hostile to the principles of liberty.
Alexander Hamilton, author of Federalist No. 1. 10/27/1787