But then i sell my core bitcoin for Segwit bitcoin and the amount of coins stays the same right? How can i increase my coin then?
you are mixing things up. the "battle" is between segwit (core) and bucoin (bu). bucoin will be nothing more than an altcoin. if you calculate from there, then it's basically free money in case the fork creates 2 seperate blockchains and you sell bucoin.
But is this why the price drops so much right now?
Am i missing something?
I see that the price went from 1250$ to 1000$ in less then 2 days. Does this all have to day with the battle between SegWit and BU?
yep. bucoin has already an advantage when it comes to pools signalling support, but the fact that bucoin needs a support percentage far lower than segwit to activate, is what gets the market shaking. as you can see the price went even briefly below $1000 just now. it's very sad seeing the market go full panic for nothing. nothing in the way that all of this could have been prevented by pools supporting segwit.