Powder Coating

[Forrest r]

I have a lot of molds that throw large for caliber bullets. Even though most of my casting needs is done with 8/9bhn alloy. I size those oversized bullets and the pc them and size them again. My pc adds 2/1000th's to the bullet diameter.

It may sounds like extra work but it pays off in spades when using the final product. A quality bullet with a square base is priceless. I typically cast 20# to 30# of a specific bullet & cast 50#+ total in I session.

H&G #68 clones (hp and swc), they cast @ .452" so I pc and size them once. Typical casting session 30#+.

A 640 series 35cal bullet (158gr fn hp/170grfn) that casts @ .359"+. These I size to .358" & then pc and re=size to .358". @0#+ as cast.

 

[BeachBumShooter]

I have been powder coating projectiles in .32, .38, .44, and .45 calibers for about a decade now with very good results.
When pushing the bullets through my Lee sizers I use a light coat of 40-40-10 homemade lube to keep things running smooth and that extra touch of lube I feel like makes them shoot even better and I get no noticeable extra smoke or fouling.
I stopped using colored powders a long time ago. I like to use Eastman's clear gloss hot coat powder which makes the bullets look like traditional lead bullets and hides any imperfections that my shake and bake method produces.

Another tip is I water quench my bullets right out of the oven to regain some of the hardness loss after they are heated to 400 degrees and it makes them easier to brake them apart.

 

[oink]

...I size those oversized bullets and the pc them and size them again...

How do you size them before coating without lube? I wouldn't think you could coat lubed bullets. And I wouldn't think you could size without first lubing uncoated bullets. I haven't used them yet but I bought some Lee sizers. I didn't think my old Lubrisizer would work for the coated bullets without lube. Although, I like the aroma of fired bullets lubed with a bees wax based alox lube.

 

[2012focus]

I've finally decided to try powder coating. My questions, so far; do I size before coating, after coating or both?

Generally for bullets kept in the 1200 fps range and lower, PC and only sizing after PC works just fine. The PC will add .003" to what ever diameter your mold drops at. What I have found to work the best is to size before and after powder coating. I usually undersize by .001" then powder coat with a .007-.009'' thickness and then size to .001- .002 past what my bore slugs at. You can thicken up the powder coat layer very simply. Use the normal shake in a cool whip container method, take the lid off and add a layer raw powder, dump some of the bullets from the cool whip container onto the lid and roll the bullets around in the raw powder. Then place bullets on a tray; I use parchment paper and lay sit the bullets up right; and bake like normal. I have noticed this method will allow bullets going past the 2150 fps range to not cause lead streaking the .003'' thickness will give you at speeds in the 1450+ fps range.

 

[reddog81]

How do you size them before coating without lube? I wouldn't think you could coat lubed bullets. And I wouldn't think you could size without first lubing uncoated bullets. I haven't used them yet but I bought some Lee sizers. I didn't think my old Lubrisizer would work for the coated bullets without lube. Although, I like the aroma of fired bullets lubed with a bees wax based alox lube.

Plain lead bullets size .001 to .003 just fine without any lube.

 

[Funflyer]

IME using an electrostatic gun is the best way to PC bullets. Unlike using the shake and bake method, with the gun I can achieve anywhere from a .001" to .003" thickness easily resulting in a much smoother and evenly applied coating.
I made several baking sheets with .22LR cases riveted to them to set the bullets on for both coating and baking. While one sheet-full is baking I size the last bunch that came out of the oven, then set the next bunch of bullets on a sheet. The whole process takes about 12-15 minutes so I'm not wasting time waiting. Sizing shortly after baking lets the bullets glide through the sizing die. If I wait a day or more they get that much harder to size.

 

[max503]

Being serious here, don't read this as judgmental.
The Hi-Tek process is formulated for coating bullets. Why would someone choose powder coating for bullets instead?
Thanks.

I could be wrong but I believe shake and bake is cheaper and easier.

 

[max503]

This is my problem. I'm new at this. My powder coating adds .003 to the diameter. Ouch. I've been adding powder, shaking/swirling vigorously, and adding small amounts of powder until I get a good coating. There's little powder left in the container. I'm still working on it though. Maybe a different powder would be thinner?

Molds are throwing .360. +.003 is .363 I've got to take down to .358. Did not go well. Using some one shot, and sizing base first helped, but not enough.

I got a .361 sizing die and sized in two steps. Much better. But not a long term solution that I like. Sizing thousands of bullets twice is not very efficient. I need to get the coating thinner, or cast them smaller.

I bought a Lee TL-358-158 SWC thinking those are supposed to throw smaller. Nope. .360.

The powder that someone on another site sells specifically for coating boolits adds a lot of girth.
One day, a hoarder friend of mine said, "I've got some powder you can have." It was old and nasty looking, but it was free.
That stuff hardly adds any girth.