First try at powder coating

[Mike3855]

I finally got around to trying powder coating some .357 140 grain bullets I cast this winter. I used 1 quart round plastic bowls with lids I got at Walmart, .25 gram black Air Soft Pellets, and a piece of old wool blanket to shake the plastic bowls on and hopefully build up some static. To get the coating that looked good to me, I coated twice. I drilled 5/16" holes in some cheap Dollar Store pans so the bullets could be baked with nose down in the holes. Bullets were quenched at end of baking in ice water.

I loaded the bullets at high end of cast bullet data and shot them into newspapers soaked in water, and average penetration was 8 inches. Range was 10 yards. Alloy was straight wheelweights. I'm really surprised at lack of any expansion.

Here's a picture of a couple of bullets coated twice before sizing.



After sizing (Bullet on right is red and white powder coat mixed 50/50)


Bullets recovered from soaked newspaper


The powder coat stripped off in the newsprint, not in the barrel. Barrel only had burned smokeless powder residue in it.

This is my first attempt at powder coating, and I'm really liking what I see. I think I'm going to like this new addition to an already addicting sport.

[carbine86]

If you are wanting better expansion I would suggest avoiding the water quenching once done with the baking. If you water quench the bullets while casting the baking proccess actually anneals the bullet to a softer alloy (not much). Remember the softer the alloy the better the expansion.

[bangerjim]

You really do NOT need to water drop boolits after PC'ing especially if you are worrying about expansion. Water dropping is an old school technique to get more hardness for cheap from the Sb in the alloy......before the introduction of PC'ing. The powder coating protects, adds a hard shell (est 45 Bhn), and eliminates need for lube.

You can shoot softer lead and save your more expensive alloy. You want softer to get expansion.

I have found that coating old boolits can be tricky. If they are stored in an air-tight container, they generally work, But if just stored in a can or bin, oxides will impede the static function and the powder will not stick nearly as well. I NEVER need 2 coats of anything! If I need a 2nd coat, I find out what is wrong and correct it so one coat does it all.

If I coat old boolits, I rinse them in laq thinner, dry them, and they coat perfectly. Some claim mineral spirits increases the static effect, but I have not seen that in the tons of experiments I have done with this stuff.

Check your coating with the hammer test. If boolits pass that, they are good to go.

Welcome to a fascinating aspect of reloading!

bangerjim

[Mike3855]

Thanks for the input! I shot some of those bullets lubed without coating, and they expanded normally. I was just surprised that the twice coated and quenched bullets turned out as hard as they did.

I would bet the reason I had to coat twice was twofold. I used the powder coat from Harbor Freight, and the humidity has been high, above 75% for what seems like forever. Right now it's 89% humidity and getting a few rain showers. Should have better luck as it gets warmer and humidity gets below 50%.

I'm also going to buy some better quality powder coating, too. This is a lot faster, and a lot less messy, than lubing bullets. The powder coat didn't get burned off the back of the bullet, either. That's good as it will keep leading down to nothing, unlike lubed bullets sometimes do. Cleaning the pistol after shooting 50 rounds was a snap; just like cleaning after shooting jacketed bullets. No carbonized lube and messy soot to remove from the cylinder or around the forcing cone. That in itself makes the coated bullets worthwhile. I forgot to mention that accuracy was better than the lubed bullets I'd shot earlier, so there's that.

I finally found my 350 and 400 grain bullet molds for .458 bullets and will mold and coat some of them after Memorial Day. I want to try the coated bullets in my Ruger #1 after I get some better quality powder coat.

I've read and re-read the sticky threads on coating while it was too cold and humid to do the coating, and learned a lot! Just need to get at it and get some experience doing it.

[Beagle333]

Another happy boolit coater. It certainly is a different way to do things. It works, it's cleaner, and it's fun! What's not to like?

[EKE]

Mike3855

Thanks for posting the pics of the recovered bullet. I may have missed some in other threads but yours are the first ones I recall seeing. I was wondering what they would look like and how the coating was holding up. The ones I'm coating are HF red for now and soon I'll be adding some of Smokes blue. I have a friend that wants some done black but haven't tried that yet. He doesn't cast and reloads very little. Since I mine the berm when I'm done shooting I want the brighter colors. He can search for black bullets if he wants to.

[Mytmousemalibu]

Something that has been working for me anyway, spread your boolits on a cookie sheet and heat'em up with a heat gun or hair dryer, they are too hot to touch in a matter of a few minutes, which seems to cook off any surface moisture and increases static. I just shake n' bake mine and don't even add BB's just boolits and powder only. Let them cool till they are warm to the touch before adding to the powder, if they are too hot still, the powder clumps to them. Doing a quick preheat like this I am getting a very nice uniform coat and they come out of the oven purdy!

[carbine86]

Something that has been working for me anyway, spread your boolits on a cookie sheet and heat'em up with a heat gun or hair dryer, they are too hot to touch in a matter of a few minutes, which seems to cook off any surface moisture and increases static. I just shake n' bake mine and don't even add BB's just boolits and powder only. Let them cool till they are warm to the touch before adding to the powder, if they are too hot still, the powder clumps to them. Doing a quick preheat like this I am getting a very nice uniform coat and they come out of the oven purdy!

I do something similar. When I know I am going to powder coat and its warm/sunny out I have an old black plastic tool case that I fill with the bullets I am going to coat. I put it in the sun open against my house in the driveway. On a good day they are hot within 15 to 20 minutes and stay hot until the sun disappears.

[Mytmousemalibu]

Thats a good one too save for using electricity I suppose and can be left unattended to do their thing while I can do something else. I do love the preheat to cook of any moisture, i'm sticking to doing it and with the heat gun, it literally is a few min and they are stinkin hot! If you've ever held a torch to ambient temp metal, especially aluminum, it sweats moisture like crazy when it begins to initially heat up, lead will do the same to some extent. I'm in Kansas and its always miserably humid here so cooking that water off is a good deal. Water an PC don't get along.