Heller said the weapon. Nothing about bullets. Liberals will do what liberals will do. Congress will pass an ammo tax and magazine tax. Or outlaw them all together. The law does not imply anything about functioning guns. Only the right to bear. Back in the day the law was written, most made their own ammo. The law does not imply what you said.
Utter. Nonsense. The Court will always consider the telos of a law, what is its purpose, and is that purpose advanced or impeded by some proposed modification of that law. In Heller, the law for DC gun owners was deemed so onerous it amounted to a substantial ban on handguns, and not because ownership of the firing mechanism was prohibited. Clearly under the DC law you could own the firing mechanism. But the restrictions of the DC law made it virtually impossible to use the gun in those self defense scenarios which the Court saw as the core telos (purpose) of the 2Amdmt.
Thus Heller turns on that same inference of usability for lawful purposes (such as self-defense) which you seek to deny. If a law says you can own it but you can’t use it to protect yourself according to its purpose as a weapon, that law is in violation of the Constitutional provision as understood by Heller. Otherwise, you accuse the founders of idiocy, of guaranteeing a right to own and carry museum pieces and flowerpots as a defense against armed criminals.
But the founders were not idiots, and we can safely infer they meant “arms” as weapons capable of fulfilling their lawful purpose, just as Heller concludes. If it helps you, think of the bullet as a little moving part of the gun, the part that when ejected kills or injures the recipient, thus the one part most necessary to fulfill the purpose of a gun as a weapon, and therefore as much under the protection of the 2Amndmt as any other part of the weapon system we call “gun.”