Originally Posted by HawkI
Originally Posted by Yondering
Originally Posted by HawkI

Dropping them out of the bake is actually annealing/drawing them a bit; the temp to bake isnt high enough to treat the metal and is actually softening it.


Sorry Hawk, that is not correct. Water quenching after baking does harden the bullets. If you air cool after baking, it has approximately the same result as air cooling from the mold. 400°F is plenty hot enough to heat treat bullet alloys.

I can also say from experience that powder coating is nothing like graphite-coated bullets; powder coating is much tougher and handles higher speeds, while being a lot easier to apply.



As to the OP - I didn't watch the video but from your description, it doesn't sound too surprising to me. I don't know that I'd claim a porcelain (or whatever they are these days) dinner plate really simulates bone though since it's a lot harder.


400 degrees for 20 minutes isnt going to achieve the hardness of 450 degrees nominal for an hour or even cadence dropped from a mould.

If you had a bullet at 22 BHN that was water dropped, re-heating in a paint bake application is going to give you a lower hardness. It will still be harder than the alloy air cooled.

Im betting the OP bullets are 15 BHN....


I've found through several moulds that the alloy doesn't reach the same hardness it had after initial quench has had a chance to fully harden. They don't go soft, but the difference ends up somewhere between an air-cool and a water drop. The bigger bullets like the 44 and 45 cal I notice the change in hardness more than for the smaller 35 cal ones. I don't mind for my applications.

Powder coating is VERY tough, and covers lots of sins. I have no leading running PB coated bullets out of various handguns at top pressures, and above. I run a 125gr powder coated Lee RNFP at 1450 fps out of a 9mm carbine with Longshot. That has to be getting near 40k psi. No leading, no coating in the barrel, and with a 4x scope, 2" at 100 for 5 is easy. There are advantages to the powder coating.

I belong on eroding granite, among the pines.