when turning sv_cheats 1, type in host_timescale x
host_timescale 1 is normal speed,
host_timescale 1.1 and up is faster speed,
and
host_timescale 0.9 and lowers is slower speed.
I put host_timescale 0.3 and it slows everything down. You, the enemies, the guns, and the reloads.
The sounds are not slowed, however. They're delayed with the actions.