This is the first time I've heard of someone having a problem which leads me to believe it is something other than the trimag. Like said above, try the mag retention spring (or whatever it's actually called). Although 3 magazine are heavier than 1, that should not make a difference. It might, however, point out when the action isn't holding mags like it's supposed to.
In other words, maybe your gun isn't holding mags in the correct position (or loosely) and it is only apparent when the extra weight is attached.
In other words, maybe your gun isn't holding mags in the correct position (or loosely) and it is only apparent when the extra weight is attached.
