This might be old but I’ll answer anyway.
I found most guns on the television shows and feature films to be real. the fake ones were usually only if it was in the bokeh of the background.
Anyway, to remove the tips, have you tried just tracking the tip of the gun and then applying secondaries in a color correction application? You could go into premiere and just highlight color, and expand the range a little, and because it would be contained in a mask, it would only effect the area your working on.