Powder Coating Cast Bullets

[38ExtraSpecial]

After following the threads on cast boolits I decided to give it a shot. It's an inexpensive way to up the performance of cast lead a little. Or to eliminate leading on a problem round or in a problem gun. Some guys are experimenting with dissolving the epoxy in acetone and tumble lubing. Then baking when dry. Adding another coat or two if needed. Seems much faster with less waste, but I haven't tried it yet.



It was definitely easy. Just slow to coat a bunch of bullets. I'm going to work on a few ways to make it more efficient.

I used an epoxy based gloss black powder coat. Lined the .40 cal on top of small washers on a baking sheet. That kept the powder coat from creating flashing at the base of the bullet.
Loaded the 308 on a sheet of aluminum I had drilled just a bit oversized for the gas check shank. When the powder built up after a few runs I had to wait for the plate to cool then scrape the paint off and start again. I also turned a few of the .308 upside down so I could coat the bases as seen in the pic above. I wanted to see how they shot without a gas check. Maybe I can eliminate the need.

Anyone else on this forum powder coating bullets or epoxy coating yet?

 

[jpm]

I'm curious if you mic'd them before and after to see how much the powder coating adds to the diameter?

 

[38ExtraSpecial]

I didn't mic after.
I just sized them when I was all done. They sized beautifully. I hit them with some dillon case lube to help with sizing. Figured it would keep down on the tackiness of the bullets going through the die.
Not that they're tacky at all, because they're baked and dry. But if you don't have a traditional lubed bullet to pass through the die every now and then it helps.

 

[jpm]

they look beautiful!

 

[38ExtraSpecial]

Thanks man!
Ok so here is a shot of the plate I used for the .308.


I just found and in sized bullet and its about .002" to .003" of paint on there

Here is a before and after pic of a bullet as coated and one smashed with a hammer. Just barely making a few tiny hairline cracks in the paint. This stuff is tough and stretchy!

 

[EddieCoyle]

Seems like a lot of work.

 

[38ExtraSpecial]

Yeah it is.

Gave me something to do in the shop though.

I have been having issues with leading in 40 and I think I'm going to have to resort to a poly coating like on bayou bullets.

This was just something fun along the way. I think it would be too much work for pistol volume shooting.

Unless the powder dissolved in acetone works as well as some guys are saying.

 

[CockedAndLocked]

Isn't it easier to clean your gun?

I've been shooting cast bullets for decades without any problems.

Sent from my Droid using Tapatalk 2

 

[38ExtraSpecial]

Do you shoot them in 40?

I would have to do a lot of cleaning every 25 rounds or so.
This is as bad as I've ever seen lead build up. I'm sure it's a combination of things but so far harder lead, bigger size bullet, and slower powder have not worked.

So I figured I have the tools I might as well waste a few hours playing around. It wouldn't be the stupidest thing I've wasted 2 hours on before.

It was fun. I learned a little something going it too. Can't complain about that.

 

[Boris]

there are ways making anything more efficient if it adds benefit.

I'm completely lost on what you are coating the bullets with. Powder coating paint is actually powdered plastic that's coated statically and baked. Most epoxies don't need solvents at all, they are two part mixes. If you are dissolving some crap in acetone, that's technically can't be an epoxy. So what are coating these things with? Can you through in the brand or source of the paint?

 

[38ExtraSpecial]

From what I understand there are different types of powder coating powder. These specific types are epoxy based.
Can't think of the name off hand but most guys on CB forums are using harbor freight or similar cheapie epoxy based powders.

These epoxy based paints can actually be dissolved in acetone or I guess MEK
I found that out when I powder coated a knife and wiped off some oil with acetone. The acetone melted the powder coat really easily.

I used a powder coat gun to do this. Other guys are using the acetone method and allowing the coat to dry, then baking for a hard and even finish. Coating a second time if need be to even the paint.

Check out cast boolits forum for a few threads on the subject. Also there are some guys using 2 part liquid bake on epoxies thinned with acetone or similar solvents and then baking the finish on.

 

[38ExtraSpecial]

http://castboolits.gunloads.com/showthread.php?t=87768

http://castboolits.gunloads.com/showthread.php?t=171403

Come on you know you wanna powder coat some .308 surplus pulled bullet so you can use them in those fangled Russian bores ; )

 

[asp]

Boris, Mike is using the method you describe with powdered plastic, statically charged, and baked on. The type of plastic powder he is using happens to be a thermoplastic epoxy. Thermoplastic = melts and resets and has similar strength. Thermoset = doesn't change shape and retain strength with melting. You're right that epoxy is a two part mix to form the epoxy, but this is already cured and somehow formed into powder. I think he was just being extra-specific as to what type of powder he was using. I had to think about that twice when he first described the process to me too.

Most epoxies are cut by solvents- acetone or MEK usually does the trick- dissolve some of the powder in acetone and tumble lube the bullets. When the acetone evaporates you're left with a plastic coating without having to do any baking. But, we haven't tried that yet. If I'm not mistaken, it has been done successfully, just not by him or I. Yet.

Yeah, cast bullets in .40 S&W has been a biach.

edit: insert 'no good comes from a .40' comment here

 

[Boris]

so these bullets then don't need to be lubricated, just sized? I don't have a lubricizer, so if this method works, there are some ways to speed up the process. May be using a dipping tray to submerge a set of bullets. Acetone is pretty light, easy to evaporate. May be setup a pass through drying oven?

 

[asp]

Correct, no lube, just size. A lee push-thru sizer might be one of the cheapest solutions. I've never used them but I think they mount to a standard single stage press. Yeah, if this works there are definitely ways to speed up the process.

Mike and I did this on Sunday (mostly him while I was casting) but we will be shooting the test batches on Weds night. We powder coated some of my .45 and some of his .308's as a control group. We know they work with traditional lubing methods, so hopefully they work just as well with this.

 

[mac1911]

I casted and loaded for my 40. The only bullet/powder combo that did well and did not lead up with in 50 rounds or less was the lee 401-145-swc sized to .401 /power pistol powder useing a home brew mix of alloy simulating 10/1 alloy.
you guys seem to have the same issues as me.....idle time and I try to do things I know are not really time wise, worth it. I did the copper plate thing also. I did how ever have limited success. Only issue is I could not get a even coat with more than 4 bullets in the tank...
I would like to see a recovered bullet pic.

 

[38ExtraSpecial]

Mac.

Good info ill give that a try. Check out the powder coat thread. The last page or two have some pics of hollow point expansion with PC bullets. Pretty nice.

 

[asp]

Mike and I shot these tonight. Zero leading, shot fantastically. My bore slugged to .4005 and my sizer is only .4008 (I need to lap it out a little bit for traditional lube) but even still with the powder coated bullets- no problems. His fed a little funny but I think they were just seated too long. Still no leading, and his were loaded a little hotter than mine.

It's great that powder coating works as well as it does, but I don't want to have to rely on it. Stupid .40.

Mike recovered a bullet that hit a rock. Tons of expansion, awesome weight retention, and you could still see the powder coat below the lube groove. I'm not sure if he brought it home or not and I forgot to snag a pic.

 

[38ExtraSpecial]

Didn't get to bring it home. I forgot all about it till now

I think this is a little time consuming for pistol ammo, but would be perfect for lower volume rifle ammo.

I'm going to try some of the 311365 next to see how they shoot. Lets see if I can push them to 2500 fps or more.

 

[crazymikie]

Have you slugged your barrel? Maybe you just need to size your bullets differently to prevent leading.

 

[asp]

We've both tried that. His slugs big, I think a little more than .402. Mine came in around .4005. My sizer die makes them .4008 (not really large enough but still worked for powdercoated) and he lapped his out to produce .403 boolits. I'm waiting to modify my sizing die till I know what works. The best (but still really bad) leading I've had was with .403 bullets in my gun with a light load of a slow powder. With 50/50 and pure COWW the leading looks like blow by, not like it's built up on the leading edge of the rifling because the boolit has too much rotational inertia for the softness of the alloy. The next trial is going to be the batch that I just cast last week. I used an even amount of pure and COWW and added a few oz tin + water dropped (extra hard). I sized a handfull last night but won't get to shoot them for another week or so tho. Thanks for the suggestions, keep em coming. Willing to try anything at this point.