If you didn’t have much to trim you most likely didn’t size them enough. A lot of LC once fired is most likely machine gun brass. Their chambers are on the large side of SAAMI to make sure the gun cycles in most conditions.
If you weren’t measuring 2.020 or near that you didn’t size them enough. Run your die until the ram/ shell holder cams when pressing against the die. Or get a set of small base dies. I have been there. I feel your pain.
