I had the same trouble as you. I think the problem is that I’ve only ever seen “gunning for”, specifically. For example, I’ve never seen “gun for” as in “Man, t

I had the same trouble as you. I think the problem is that I’ve only ever seen “gunning for”, specifically. For example, I’ve never seen “gun for” as in “Man, that’s one determined team! I bet they gun for nothing less than the win!” — I would expect that to be phrased “… are gunning for nothing less …”.