I use CFE 223 for some loads, especially for AR 15 rifles. It is dirty and leaves a residue in them. But it is easy to clean. I can always tell when someone at the range is using it, as it has a peculiar odor. Smells like it has ammonia in it, which would aid in reducing copper buildup. However, I find it difficult to meter from round to round. Getting it to repeatably measure, within .01 grain accuracy, can be difficult.