I suspect the problem isn't the ammo or the gun. Some cans just aren't very quiet on pistols. Monocores like the one you have are typically much louder than something with individual baffles. They also suffer from a loud FRP. Weaker ammo will certainly help, but with the right can it isn't...
Worst case it gets stuck in the barrel? Just bring a cleaning rod to get it out, and make sure it exits the barrel before shooting another. I usually just fill the cylinder to the top and compress it, but that's me.
I’ve been asked to produce stamps at GGC, but only once. GA firing line has asked me multiple times, but only by the female employee. Nobody has ever asked for a stamp on my sbrs.