We had to pull this out of a girl's nostril the other day.
She had it in for 2 days by this point. Ear piercing studs are not long enough to be able to accomodate swelling and there's no way to clean it aside from spinning it, which turns more dirt and nasties into the piercing. In her case she couldn't even grab it to spin it.
The stud was finally wrenched free and a captive bead ring was inserted but the damage is still clearly visible. Even from a distance the crater is very noticeable. The scar from this may fade in time...
Who in their right mind would elect to pierce someone with a stud gun? A hole puncher with a money hungry streak that doesn't care how you heal and doesn't care about your well being.
I must note that this was done in a flea market to a girl who was underage and didn't want to wait for mom's consent. I think she's learned her lesson... ;)
There's a reason it's called an ear piercing gun and not a body piercing gun. This thing does more damage than good.