Unrelated grad school -> IB analyst?

Hello WSO and thank you for any and all advice pertaining to my unusual situation.

I graduated in 2015 with a 3.7 GPA out of a non-target with a degree in mathematical economics, spent this last fall at military training (I'm in the Army Reserves), and am about to start a graduate school program at a state university studying math and computer science. However, I'm coming to realize that this was a mistake: I hate academia and research more than I ever would have thought, and I want to enter finance because it's more fast-paced and more lucrative.

The specific topics that I've studied are not really useful from a quant perspective, so that's out. However, when I was an undergrad I was part of an investment banking club, I studied a bit of accounting, and I've been reading more about careers in investment banking recently. I've had plenty of experience getting used to long hours and painful work, and I'm very confident that I would at least withstand the pressures of the job. Therefore I would like to enter investment banking as an analyst - an intern if need be. Clearly it's too late for me to join recruiting for summer analyst internships or full time work in the fall. I'm thinking of doing a lot of networking this spring and summer, and then joining as a full time intern or analyst in the winter or spring after my fall semester (or road trip across America, or something: I may drop out of grad school by then). Also I'm still in the Reserves so that takes a few weeks and weekends out of my year. I really want to do this, so to put it simply: what are my chances of making it work?

Thanks,

MathsGuy7634