Powder..patch..ball FIRE!
12ga pump - 8 round tube alternating 3” #000 shot and slug.
And I practice....
I did living history during the American Bicentennial.
The Brown Bess musket is nominal 12 gauge (.73 cal). I used to load mine with AA wads & BBs. Also, “buck & ball” was a tactical load during the RevWar.
At close range, there’s nothing like a shotgun.