Is a shotgun really better than an AR for upstairs bedroom defense?

It's mostly generational gospel. Here's the honest version:

**The "shotgun is superior" argument** comes from the pre-modern-defensive-ammunition era, when 5.56 55gr ball ammunition was common household ammunition for an AR-15 and would overpenetrate household walls badly. The shotgun with 00-buck was meaningfully better-behaved in that environment.

**Modern reality:** 5.56 with modern defensive ammunition (Hornady TAP, Federal Tactical Bonded, 55-62gr soft-point) actually has *less* wall penetration than 00-buckshot in many tests. The 5.56 projectile destabilizes on impact and breaks up through drywall. 00-buck pellets maintain trajectory and velocity through a shocking number of interior walls.

**Recoil matters upstairs.** You will be firing from a dynamic position (likely not from a shoulder-locked stance). Recoil management during stress is a real factor. The AR is dramatically easier to shoot well under stress than a defensive shotgun.

**Capacity matters.** An AR-15 with a 30-round magazine has three to five times the capacity of a standard home-defense shotgun. Mass-shooter scenarios aside (and those are not home-defense), multiple intruders or multiple controlled shots per threat are scenarios where capacity becomes decisive.

**My honest recommendation:** the AR-15 you already have, loaded with proper defensive ammunition, with a weapon-mounted light, is an excellent home-defense choice. It is probably better for your specific scenario than a shotgun would be.

Where the shotgun still wins: extreme close-range (6 feet and under), specific outdoor scenarios, and users who actually train with a shotgun regularly. If you don't train with a shotgun, the AR-15 you do train with is the right answer.