I should stay out of this.
BUT I have read all 139 posts and replies and only one person has mentioned using a propane torch to heat a mould. Kroil has been mentioned once.
I don't want to come off as being an expert or a know it all but I try to keep it simple and just use some common sense.
Occaisonally I have some dificulty trying to cast perfect boolits. Most of the time when I start to cast I heat the mould with the torch and the first pour delivers perfect boolits. That being said I would never play the flame of a torch on the sharp corners of the inside of the mould blocks. My torch has a four or five inch long about half inch in diameter flame and it would take some serious effort to melt aluminum with it.
I had a four cavity mould once and I gave it away, too heavy. I now have about thirty eight boolit moulds and all are one or two cavity.
Armoredman would be well advised to go with a single or two cavity mould to start with so that he could enrich his expertise with experience.
Use enough heat!!!!!!!
Life is good
From the minds at CastBoolits
Bravo 462, very well said and precisely the reason I am a member of this forum. I've learned and also re-learned many things from the forum members. Both things that do work and many that don't.
EDIT to add: Here is a fascinating casting/handloading tip from sagacious that is a perfect example of the knowledge here. This therad is in the Shooters sticky forum. I don't care how long I cast bullets this is something that I never would have thought of. This is extremely effective, economical and quick. It's not really off topic from this thread because I took this idea and used it to clean molds. Very effective and fast.
Citric Acid Brass Cleaning
Rick