the one thing I saw was a slng shot or catapult bow using a ring about 1 inch in diameter between the forks on a sling shot you can use
an arrow and take medium game as an arrow has a lot of weight and potential lethality over just a ball.
All of this without altering so it could not be quickly changed over or canibalizing your sling shot to a point of destroying it.
As well you can use any type arrow home made, wood to carbon fiber, with a zebco style reel mounted on the bottom it would make a great fishing bow
A fluflu arrow and it can take birds and you can be off a bit and sitill get a fatal strike
a lot of this information is easily found on youtube
I consider only a few weapons other than firearms to be vital a spear / fishing gig a way to project lethat projectiles and the bow is great but here
it is far from handy to carry a compound bow is great until it breaks a part and or you run out of arrows made to take the force of a compound bow.
also the speed of reloading and size all goes to the catapult or sling shot adding in the arrow firing ability weight it makes the cut in all catagories.
Wally we have been talking about weigh of BOB's and I am in your camp I am not as young as I once was I can carry quite a bit but
for how long ? one day I will have to sit down and minimize my BOB and cache the leavings so I can continue on.
in my area I will have to move 300 to 500 miles if on foot I know the troubles I will face and if I get down to bare minimum a sling shot will be in that
BOB as well as a spear tip & gig.
Arrow heads can be made in a wood mold carved with a knife and melting wheel weight lead it only takes 750 degrees to get fine pourable lead.
easily done on a camp firee, flint knapping is great but it ain't eazy and it is a tallent.
#000 buck shot single or double mold from lee and you can scavange weel weights and make it into shot and into simple flat arrow heads.