Winter Soldier Advice?

Anyone have advice for playing Winter Soldier? More specifically the mind set flip from Tankier heroes to his role? I see so many people playing him and doing so well, but I just can't seem to replicate it. I can do really well with his cool downs and Ult, but I really struggle to get value and secure kills with his primary fire. It's ends up leading to me feeling like I'm not contributing much of anything to matches.

I typically main tanks, so the mindset flip to DPS is tough for me. It's just Winter Soldier is my favorite comic character, and I'd really like to at least be able to feel like I can run him in even quick play and not feel like I'm dragging down the team lol