Sit down representatives from the gun industry, gun lobbyists, NRA, hunters, etc. and simply ask them how to prevent these sorts of senseless homicides. Maybe they come up with some useful ideas, in which case something should be able to get done, or they come up with nothing and we move on without them.
edit to add:
I fully expect the NRA will have nothing to add to this conversation, and I wouldn't put it past Biden to (rightfully) tell them to go fuck themselves. Other gun groups (hunters, law enforcement, etc.) might actually be able to contribute.