Cajun - Put it this way - if I were at a gunshow, and I saw a guy selling remanufactured/reloaded ammo for a good price...hell, for a STEAL, and when I went to buy it the only guarantee I got was "I'm very careful, shoot at your own risk" I'll be shooting Wolf or WWB instead, at my own risk.
There's too much at stake with that sort of thing, in my opinion, to not be able to offer the customer some proof that if your product screws them or their gun up you'll be able to make it right.
*Also* Saying to someone "shoot at your own risk" doesn't do a whole lot to inspire confidence in your product. It implies that you, yourself are wary of the quality. I'd not want to buy a car from a car dealer and as I'm driving away hear them say "oh, by the way, drive that sucker at your own risk." Ya know? And even if someone did buy your ammo after hearing your "disclaimer", "use at your own risk" doesn't really amount to a "disclaimer" in the first place. We all use products at our own risk, everyday. It's already assumed that we do, so you're not adding any extra protection for yourself by re-stating it.