I got an S&W 1950 that has had some AR brass bind up when I shoot in DA. It does not bind in my 25/17. It appears that the hand is binding on some case rims. I measured case rim diameters and found that diameters ran from .510” to .514”. I took cases in .001” increments and off to the range. No binding at .511” or less, binding starting at .512” and really tight at .513”. Approximately 60% of the cases were .511” or less now I have started trimming the rest.