Can I test a raid on my base in the Sandbox?

Yes. Buildings in the Sandbox take damage exactly as they do in the real game — bullets, melee weapons and tools, arrows, spears and explosives all work. So you can blow a wall and see what it actually costs.

You can't die. The player stays invulnerable, so you can stand next to your own C4 and set it off. Nothing you do hurts you.

Demolition still has no time limit, unlike the main game where a piece can only be demolished in the first 10 minutes. Use whichever is quicker: demolish to reshape the build, explosives to test how it holds.

Structural collapse works the same way, so after a breach you'll see exactly what comes down with it.