In two of my 38 Special revolvers (S&W K-Frames) I get at least 1-2 not go "bang" per 12 rounds. I loaded up close to 700 of them previously for PPC League (Alliant Bullseye with lead 158gr SWC) and I have been disappointed. Once this batch is done I will only use other brands (Remington, Federal, Winchester) for my revolver.
Have you lightened the trigger on that revolver? My revolver will only ignite Federal. I use those +P in my new lever (5.4gr Unique under 158gr coated lead). It will also ignite that load when I use SRP. None of that works in my revolver.