For defensive purposes I don't see the need for thousands of rounds. By the time you empty your shotgun and you still have someone shooting back at you, you are fuxored anyway. The idea of self defense is to have a shooting, not a shoot out.
Given ammo shortages, fluctuating ammo prices and factors I am not even aware of you should have a good supply of ammo on hand. At least a case of ammo for each caliber you have several guns chambered for.
"I do not aim with my hand; I aim with my eye. He who aims with his hand has forgotten the face of his father.
I do not shoot with my hand; I shoot with my mind. He who shoots with his hand has forgotten the face of his father.
I do not kill with my gun; I kill with my heart. He who kills with his gun has forgotten the face of his father."
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