Not Home Depot parts. They don’t stock 4140 steel. Anything will burst under the pressure of a .50 cal cartridge.
Specialized material and process, I know. Just pointing out how far people CAN go with stuff near at hand if they have the ingenuity and will to see it through.
Like Iron Man I mentioned above. Caught without his suit in the third movie he went hardware store shopping and made what he needed to accomplish his goal - necessity being the mother of invention.