My Taurus PT99 has a very large firing pin hole and primers flow back into it with even very light loads that just roll the brass out of the slide. I have gotten into some warm loads and I really can't tell the difference between the light loads and heavier loads just by looking at the primers. It has been my experience that lots of the Taurus 92/99 series guns have large firing pin holes and will allow the primers to flow back.
If I were looking at getting top velocities out of it I would go to small rifle primers, just for the extra cup strength and insurance against a pierced primer. In doing so I would also start very low and work up since the reloading data does not include rifle primers.
A 124 at 1100 isn't exactly light, but seems to be a reasonable load speedwise. Any particular reason you are loading them so short? I would expect pressures in your loads to be as high as standard factory loads or a little higher with that OAL.