You can also do the citric acid thing. I mix up a strong batch of unsweetened lemonade Koolaide, add a little dish detergent and soak for a few minutes. Carefully rinse and put out to dry. No, it won't completely clean the primer pockets, but as I understand it, neither will most of the other methods.
There are other sources for citric acid, but the unsweetened lemonade Koolaide mix is almost all citric acid, and is available in most any grocery store.