Sorry, if your gonna practice like this use a dummy gun.
All firearms are loaded, All the time. Period.
Throw some sand weight into a squirtgun/airsoft and go. The first thing i did after taking my Beretta to the range the first time was buy the Airsoft copy. After fiddling with it for a bit and adding some lead soap box car weights, it has become the best (and safest) indoor training tool i could ask for.
Its also hella fun to shoot my roommate with at 2 in the morning
Your roommate is wearing appropriate protection for this type of activity, goggles etc, correct?