For discharge of the weapon you can use bullet traps that are built-in (often at a firing range or training centre).

But there are also separate bullet traps to use. A seperate bullet trap must measure up to the following conditions:
• Safely, reliably, and consistently receive bullets under all conditions and in all calibers
• Safely collect and store all bullets fired
• Safely and efficiently allow for the removal and disposal of collected lead and other debris without causing environmental damage and without violating city, county, state, or federal regulations