Random thoughts...

sure guns are better, and faster, and it would be good to always have one around just in case that u encounter armed people that are hostile. however as u said, gotta save ammo

i would have my own tribe ruling over the holy lava mountain. and we would survive by hunting scavengers and grilling them. imagine the open air festivals we would have whenever we would have new people to grill. we'd make a windmill ontop of the mountain to create electricity, so we could put together speakers and have savage rave parties

imagine the horror on the face of the people we about to grill, as we carry them up the mountain and everyone raves around them and gives them serious looks