Powder coat questions

SierraHunter

SierraHunter

Bullshop jr
Since I’m just getting back into casting I want to start powder coating my bullets. I messed with powder coating very little about 8 years ago using Harbor freight red and yellow mixed together and a vibratory tumbler and air soft BBs to apply it. I am planning to use the same method this time to apply the powder but I can’t remember the process for sizing. I think I used to size .001” under the size I wanted to be at and then just coated and shot them but have no idea if that’s the right way.

Also, has anyone used PRISMATIC powders? I see thy have the triple bronze color for about half the price of their other colors and was gonna order a pound to try out.

Thanks
 
As long as you get the size you want, it doesn't really matter either way. Powder coating is a little less exact a science compared to say Hi Tek coating, and the thickness can vary a little bit. I'd say on average you are looking about .0015" added diameter, but I've seen .001" and .002" plenty of times. If you are under .001" you are probably pretty spotty on the coating. It can depend so much on the humidity, amount of powder, how long you shake them, how much you shake off, and plain luck.

This is just my opinion, but I see zero reason to size before coating. Size after coating, and you know you will always be the right diameter.
 
blackpowdertom said:
Why turn what can be 1 step, into 2 steps
Click to expand...
Because once the bullet sized and check is seated/crimped the added benefit, no matter how insignificant it may be helps glue the check and bullet together.
Plus some molds cast big to start with and I prefer to not try and jam a bullet through sizing 4 or 5 thousands when I can do 2 thousands at a time. Less distortion, maybe, I’d don’t know. Plus if you’re using NOE sizers more than 2 thousands gets tough.
 
Those NOE sizers are absolute trash in my opinion. Bullet sizers, nose sizers. I have had zero luck with any of them. Even trying to size down one to two thou.
I like the idea of gas checks before PC. You know they aren’t coming off.
 
I've never tried any NOE sizer. Do you mean the bushing push through ones? I'm surprised, I always heard good things.

I know it can be tougher to size using my Lyman 450 traditional lube sizer. I haven't used that for quite a while. It depends on the lead hardness, but I know I wouldn't even think twice if it's under .004" sizing down.

Most of my sizing is either Lee bushing push through, or Star push through. Those are so slick, and have so much leverage. Even sizing down .010" is not out of control, although questionable for the bullet. At only .002" you can barely even tell it touched.

I've been a vocal critic of the NOE expanders. They have always come rough as a cob. They should have really changed the design, but they never responded to my emails. If polished with fine sand paper, they work way better. Maybe the sizers need a polishing too. Or ditch them, and go to Lee. They can sometimes use a polishing too.

If you use a good push through sizer like a Lee or Star, then .005" becomes nothing. You can save a ton of time and frustration skipping the extra step. I have never had a problem with gas checks coming off. I have run into some that never seemed to crimp on tight and could be twisted by hand. That can usually be cured by annealing them.

Mostly I avoid those discount brand ones anymore if I can, and I never mess with aluminum. Hornady gas checks are simply the best.
 
All NOE size dies of any flavor I have got all have no tapered leads. Sharp edges everywhere. Scrape and cut bullets. The last one I bought was a .411” die. I thought I was gonna rip my press off the bench trying to size a .412” bullet I had cast two days prior that had a bhn of 12.
Lee size dies or the ones Brad is kind enough to make for me.
 
I use the old Lee sizers.
I'm kinda lucky with the .380, 9mm, 38 special and 357 bullets. I've have a kind of collection of .35ish guns and bullet moulds.
I have sizers .356, .358 , 360.
So for all but Two bullets. (One bullet that casts at .362' gets pan lubed and goes .360.)

All my other .35ish moulds, so far have cast at .357 to .358
On those, I just cast, coat, and then size everything .358. Use them in all the bigger bores.

If I need a bullet for one of the the 380's or 9's. Then size a .358 again at .356. As the first step in my loading process.

My other calibers all seam to like .001 over and their moulds cast at that. So it's just coat and size for those.

I have one bullet I powder coat, that is an exception to the rule.
It's my Lee 125 RN .358. It cast at .360. But my 9 mm wolf barrel in my Glock clone really likes that bullet size to 356. Like ragged hole at 10 yards good.
And nothing else will shoot it good.
So that bullet I size down with Dawn dishwashing liquid as a sizing lube, to .358. Then again to .356.
Trim down a little curtain of lead that forms around the base with a razer knife. Wash The bullets really good, to get all the Dawn off. Then dry them out in the toaster oven. Then I powder coat it and size it back down to .356.
 
Last edited:
SierraHunter said:
And you guys don’t have issues with the coating scraping off trying to size back to the same diameter post coating?
Click to expand...
Only when I did not cook long enough or cooler then the listed temp on the bag. When I first started.

Now I bring up to temp.
Then start the timer once it starts to flow good. No more issue with it scraping.

If you smash one flat with a hammer and no powder comes off then your whole batch will be fine.
If not then you have not been baking them long enough or hot enough one or the other.
Each color (even if the same brand sometimes) can cook at a little different rate. Always read the directions, and wait till it starts glossing before you start the timer.
 
Last edited:
Glaciers said:
Yeah what Mitty said.
But I just cook 10 minutes longer at 400
Click to expand...
Ye,
I don't think an extra 10 minutes to be safe would ever hurt anything.
I forgot to set the timer on Eastwood Blue, once. Cooked from warm up to finish for 40 min.
It's cook time was listed 400 at 20 min. After flash over. Didn't seem to hurt it one bit. It cured well when cold. They sized and shot just fine.
 
blackpowdertom said:
Why turn what can be 1 step, into 2 steps?
Click to expand...
Because sometimes that's what it takes. I have one bullet that shoots incredibly well in several different rifles and chamberings but it casts three thousandths over what I want to begin with. It gets the gas check seated in a seating tool, then sized through a push-through sizer that knocks it back to what I want to end up with, then I powder coat them, then as soon as they are cool (and another batch is baking) I run them through a combination nose/body/taper sizing die which puts them exactly where I want them. Can't wait until tomorrow because they're too hard by then. I do these by the hundreds and load in bulk for self-feeding rifles.

I also have the Lee C358-200-RF that has a small gas check shank. Being lazy, I haven't de-handled it and chucked it in the lathe yet to bore out the shanks a thousandth. Powder coat, stand on bases as always, then seat and crimp gas check over the coated shank, then push through to complete the sizing (bullet body barely kisses a .359" die) and shoot them in my cut-rifled 336. PC makes the checks a perfect fit.
 
SierraHunter said:
And you guys don’t have issues with the coating scraping off trying to size back to the same diameter post coating?
Click to expand...

If your coating scrapes off in a sizing die, there's no chance it was ever making it out of the barrel in good condition.

Either that or your sizing die is ridiculously rough. If sizing down .005" takes a lot of effort or causes problems, even with hard 25 BHN lead, something can be improved with the sizer.

Ian's case is special, that sounds more like swaging than sizing.

And of course if you have a mold that is imperfect but you want to use it anyway, you have to do what you have to do.

Given the choice, I will never willingly size twice for no reason.
 
You must log in or register to reply here.