I shoot my Blackhawks and Super Blackhawks in twenty five round stages. I find if I shoot more than this my guns become uncomfortably hot to load/eject cartridges. I have never timed a stretch, but it is slow, aimed firing, fire five shots, eject and reload. So I shoot twenty five rounds then swap out guns and let the one cool down.
Shooting about forty rounds and my guns are simply too hot to handle. But never has had any ill effect on my guns.
Bob Wright