IMHO, I would never use Clays with jacketed bullets. With lead bullets in the .380 Auto, I like nice, soft, 800 fps loads that deposit the brass in a small pile at my 5 o'clock.
With this goal in mind, I've done some load development with Clays in the .380 Auto using 95gr LRN bullets. 2.1gr of Clays loaded to a COL of 0.950" with CCI 500 SP primers in mixed-headstamp brass resulted in 802 fps with an extreme spread of 52 fps and standard deviation of 16 fps (for 30 rounds tested). The BIG problem with Clays is you have to watch the powder drop like a hawk. It tended to bridge in my Lee Pro Auto Disk measure using the .32cc cavity.
So Clays is an OK powder for this usage, but not nearly as good as Accurate #2 or VihtaVuori N310. YMMV (and probably will...).