Over the years I have seen so many posts from those having problems with powder coating. Powder coating is a pretty simple process and getting a good coating involves just a few steps. Start out with a quality powder suitable for your application. Apply the powder to completely clean bullets. Apply an ample amount of powder coating your bullets with no bare spots. Then properly cure your bullets.
It seems that the last step, curing, generates more questions and creates more problems. Actually the curing process is very straight forward from the manufacturer's of most of the powders powders and that is bring the substrate (the surface of whatever has been coated) up to 400F degrees and keep the temperature stable for a minimum of 10 minutes. Problem is even with an accurate thermometer placed behind the glass oven door where the temperature can be monitored, the thermometer is reading the air temperature not the substraight and typically they are not one and the same. So most just add more time using a guesstimate, I know that is what I used to do.
Now I think I have a better way. I purchased an inexpensive Chinese made digital thermometer and several cheap thermocouples. Checking against my mercury serviceman's oven thermometer I found the digital thermometer, which only reads in centigrade, to be quite accurate.
I drilled a hole in a 45 caliber bullet inserted the thermocouple into the bullet then sealed it in with lead solder. Now I just set my sensor bullet on the rack in my oven with the other bullets and use its reading to know when my bullets have actually reached 400F degrees. Doing several racks at a time I found variations between the racks so placing my sensor on a center rack seem to provide a good reading.