>I think it's much more important to manage the access to ammunition. After all, a gun is only actually dangerous when it's loaded. Sure, a gun that isn't loaded can still be used to threaten people (because even then it demands attention and the utmost respect) or even pistol-whip them. But it is very unlikely to be used to kill anyone or anything.

This isn't really workable. One of the primary ways criminal gangs acquire firearms here in the US is through "straw purchases", where they have someone with a clean record go purchase a gun for them.

This works fairly well for them, but has its limits: if guns you've purchased later turn up in crimes, you're likely to face pointed questions. You can't do this too often without putting yourself at serious risk.

But straw purchases of ammunition are almost impossible to track. If the buyer is asked to account for their ammunition, they can simply claim to have shot it all already.

Meanwhile, it adds great expense to ammunition (My local stores mark up their ammo nearly 100% already, and it will become worse next January once it's illegal for me to order ammunition online). And because criminals actually use very little ammunition, this cost falls almost entirely on legitimate target shooters and hunters, who are the ones shooting tens of thousands of rounds a year.