building a speargun kids! give me a hand. first post!

hey guys! I’m new to this forum and am also new to the wonderful world of composites. now the main reasons I’m here.

I want to build a speargun. This goal is not a small one.
Spearguns are built out of carbon all the time so its not a question of Can you but its a question of how far can i push it.

how strong can one make a structure that has been skeletonized. I also realize that its all a matter of more carbon but is there any special process I need to use to make it happen. I’ve attached pictures of what I have in mind.

Could a structure like those i have attached support a load of 300lbs lengthwise?
The length would be somewhere around 30 inches total.
Any calculations I need to do in order to figure this out?

any other tips and tricks you could throw my way or maybe the title of a post you think would be good for me to read. please send my way!!!

thanks guys and girls!

Which structure are you talking about that needs to support the 300lbs, the stool or gun? The stool is made by filament winding which im guessing you’ve looked up? It wouldn’t be possible without a decent capital investment.
Cant really see your point here, sorry. Is it to make a spear gun but skeletonised as opposed to being fully moulded? Certainly wouldn’t be as strong/stiff per unit weight than a fully moulded part