@Meddler, Scruffy, Xypherous, etc. - I need some help ironing out an Ammo mechanic

I've been working recently on Reddit on a Champion Concept who uses Ammo as a mechanic. In this, Ammo is expended both when you use offensive abilities and when you perform basic attacks. When out of Ammo, you can't use offensive abilities and your basic attacks are much weaker.

The issue is getting a good skill/mechanic working for reloading. See, your Ammo doesn't regenerate normally. In the current iteration, you either get Ammo from minion/monster kills, by returning to the fountain, by staying out of combat for 15 seconds, or by using the Champion's E ability. I'd like to take out the minion/monster kill part for a better skill-based reload.

The thing I want to do is make this Champion's reloading akin to a first-person shooter game, in that it's clip-styled. The original version I had was that while you were reloading, you couldn't attack or use abilities, but could still run if needed (and use Summoner Spells). If you were caught in the middle of a reload, you'd be kinda screwed if you didn't Flash out. However, some people didn't like the idea, as it was too jarring to offensive flow and could give opponents too much of a window for counterattacks. Though I think that'd be an okay gameplay element, whether or not it's good for League is something else.

Could I get your expert opinion(s)?

The concept's most recent iteration is on this Reddit page: http://www.reddit.com/r/LoLChampConcepts/comments/2aknd6/terminus_the_war_machine/