I'm more concerned about what the citric acid is doing to the rest of your cases, not just the range-darkened ones. Also, just because the corrosion process started when the case was on the ground, that doesn't mean that you can't make it worse by using an acid concentration 20-40 times higher than what it needs to be.
Essentially, you've taken what's meant to be an optional "sparkle additive" (the citric acid), and you're using it as the sole chemical cleaning agent in your process (one drop of dish soap in a quart of water isn't doing anything significant).
It's your brass, do what you want, obviously. But if you want to know why you're getting a pink cast on tarnished brass, it's because you're acid-raping the hell out of it. I've seen plenty of darkened range brass that polished up just fine in a wet tumbler with stainless media, and didn't turn pink.
Last edited by ScottRiqui; February 11, 2013 at 11:04 AM.