Another thing to check if you are getting misfires with either pistol; are the hits on the primer centered, or slightly off-center? If off-center, it may mean the slide was not fully closed when the hammer fell, and some of the hammer/firing pin energy may have been wasted in closing the slide the rest of the way, causing or contributing to the misfire. This much more likely with the S&W, as I assume the .380 has a fixed barrel vs falling barrel, but it could still happen with a fixed-barrel pistol if the round was not fully chambered.
My experience with .380 pistols is that some of them can be very intolerant of granules of burned/unburned powder in the chamber area, and some ammo may leave more firing residue than other types/brands. If it happens only with one ammo type/brand, chalk it up to incompatibility and for best results, don't use that ammo any more.
Hope you get it figured out; reliability problems can be really annoying. Good luck!
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)