Airforce Sling Swivel Stud Set

I bought the set to replace the one I had used on my rifle for some time. The back swivel stud had failed do to the circlip popping off. As it was more than a few years old I decided to just get a complete replacement set. I only installed the rear stud as the front one was fine. The very first time i lifted the rifle on the sling the rear swivel stud failed in exactly the same way. Either the circlips are not great quality and or they are not large enough to do their job as intended.