First I seached this site for answers cuase I think I'm not the first to ask this, sorry 10+ pages of results and after the 3rd page stopped reading and just submit the question.

I have a bore hole well i use in the dry months, I capture as much rain water as I can during the wet months. During this time my tanks are overflowing and excess flowing onto the ground.

My idea is to route the excess into the well bore hole thinking it would act as a sponge storing the water for later use but I worry it may cause some unknown damage (like the walls becoming mud and collasping) Good idea or not?

No, not a good idea.

Your bore is just the water table exposed. Adding water to the bore will not store it.

Your overflow is adding to the water table already. Just a bit slower than poring it down your bore.

Thanks KB, that's why I asked for opinions cause it is something I didn't consider, gives me new outlook on my idea

Also a poor idea because you will also give direct access to the ground water of any surface contaminants.