I have found temperature control in the oven is very important. I have the parts coming from China to make 2 more PID boxes to add to the one that I am shuttling between my casting pot and one oven. I use a DVOM to keep track of the temperature in one of my ovens but it requires me to watch it close. My other oven is a digital model that maintains temperature very well, cost me $4 at the Thrift store.
In my experiments with high velocity rifle loads I would reduce the temperature once it hit 375 degrees and the oven would take a couple minutes to lower to the 350 degrees I set the oven to. The coating had time to cure and passed the wipe, smash, and the shooting test.
My elk hunt was a bust so now I am going to continue my experiments with different alloys concerning the water quenching, heat treating, and ways to maintain the BHN after coating.
I did have a batch of alloy that I water quenched and it maintained most of the "free" BHN after coating but when I repeated the test I could not duplicate it.
I may buy some tin and antimony to mix with some pure lead that came from an acid tank used in a plating plant.