Way over thinking. The Blue Collar link has over 3 pages of .223 ammo in stock. Standouts include 40 rounds of Winchester 45 grain sp for $38ish. Fiochi 50 round boxes of Vmax in different weights for about the same. A bunch of other brands to fit any taste. In a house or basic yard I’m reasonably sure any designed to expand will expand and do extensive damage whether fired from a 10” or 16” barrel. Buy & blast for function. Maybe get a linear muzzle device on the chance some of the concussion might actually be diverted forward. It ain’t this hard.

“When Tyranny becomes Law, Rebellion becomes Duty”

Colossians 3:17 (New King James Version)
"And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him."