I should have been a little more specific on that post when I advised drilling a hole. On most of the trigger/bolt springs the gap between the trigger and bolt leaves/springs, what ever is the proper term is for the most part a proper gap. Down where they meet at the gap, if the metal is rounded, I've never had a problem with any cracks or breakage, but if it is sqaure, that's a crack/breaage wailtilng to happen. I have seen trigger/bolt springs that had the squared corners. Most I see on current revolvers using this style have the rounded corners.
What I was referring to if the corners are squared, a small drill can be used to drill right at the junction of the two springs so as to take the squared corners off and leaving rounded ones. Doesn't take much of a drill as far as diameter. A needle file can smooth things up and if ya want to take the time, use the file to round the edges, a drill is faster. I read of this procedure years ago when some of the trigger/bolt springs had the squared corners. I only did it once and that was to my first Colt '51 I bought back in '72, a EMF 51 Navy in 44 that had a #@%&*#$%^ action and sucked caps like a vacuum cleaner, but back then cappers were not as well built as today and some shooters (including me) were not as well informed /experienced as today. Few books, no internet, not as many cap n ball shooters as today. Sometimes the blind were leading the blind. LOL!!! Hope I 'splained this OK.