I have been following and reading up on HY TEK for some time. I ordered the black powder from High Performance Bullet Coating last year. I gave it a try last year without success. I didn't have a lot of free time, and I had a good stock of lubed and powder coated boolits. I want to give HY TEK coating another try for the rounds that I shoot the most of, like 38 special, 9mm, 40s&w, and 45 ACP. I just takes too much time to stand them up to spray them with powder coat.
I mixed a new batch of the solution per the instructions. Coated the boolits, 5ml to 5lb of boolits, and let sit overnight in the wire mesh pans that I made. Heated my convection oven to 400 ish degrees. I used an oven thermometer to verify the temperature. Placed the boolits in oven and started the timer on the oven after it reached back to temperature. This batch failed the smash test but passed the wipe test.
Next batch I had read the recent thread of contaminated alloy and the use of acid to leach the contaminates. Ok this batch I soaked the boolits over night in acid. Rinsed thoroughly and let dry for a few days. Coated the boolits with 4.5-5 mil of solution to 5 lb of boolits. I let these sit overnight. And baked them in the same manner. 400ish degrees with the timer starting after the oven reached back to temperature. Once again failure.
Now a few question.
First what difference does using MEK vs acetone make and any suggestions on brands. I have used the acetone sold at Walmart, so im wondering if its compatible (purity)
I have read several times that it's more of a stain and too thick of a coat will cause a failure. All the pictures that I have seen is a finished boolit and couldn't find one of a freshly coated but not cured boolit. Can anyone help out with a picture of what the "stained" boolit looks like. My research on failures suggest that I am adding too much solution to the boolits, but Im using the ratios listed in the instructions. Would it be better to try adding say 3 ml to 5lb of boolits or adding a little more acetone to the mixture. Something like 110ml acetone to the 20 grams of powder. No problem with having to use multiple coats.
On all occasions the solution was mixed at least an hour before use and was shaken prior to use. Im using a children's Tylenol syringe to measure the solution.
One thing that I did notice about the powder was that there was small brown looking clumps in it. Not many just a few. They were present when I first tried it last year also. The powder had been stored in the house since I got it. Any chance that these clumps are the catalysis and it has separated from the dry mixture?