Is it possible (from where i'm at) to increase my vertical to dunk?

Im 18, 6 feet in sneakers. Im able to stand from under the rim, jump and can grab it (only with one hand though). If I get a running start I can hit the rim with the center of my palm.

If I keep training legs more would I be able to dunk or will my verticle eventually cap off? Its a huge goal and I dont wanna spend more time than I have to on training legs if it wont work.

Let me know if you get any suggestions. Thanks