My Ruger SP101 357 magnum, and my Sig P250 in 357 sig. They are loud in the indoor range.
A guy next to me was shooting a Glock 20 with some handloads. That sucker was LOUD! It was actually distracting me while I was shooting. I finally leaned over while he was reloading and asked him what he was shooting over there.
GLOCKS- (19 Gen 4, 20SF, 21SF, 30SF, 42, 43), Beretta 21A Bobcat, Spreewerke CYQ P38, Remington R1S 1911, Patriot Ordnance P415, Patriot Ordnance P308, Sig 556 SWAT Classic, Colt LE6920, Kel Tec KSG, Norinco NHM90 5.56 converted to pre-ban configuration, 6.5X55 Swedish Mauser CG 1903 M96/38, Swiss K31 7.5X55, BNZ 42 K98, Mosin Nagant M91/30 1934 Tula, Ruger 10/22 50th anniversary design contest rifle, Tikka T3 CTR, Winchester 1200