First try at PC, Issue?

[hylander]

Followed directions to a T, or so I think.
They are still hot, just out of the oven.
I see what looks like run lines in them
You can see if you enlarge the pic
390 degrees for 26 minutes.
Yes temp is correct.

[hylander]

They look better after cooled.
However, after sizing to .309 it looks like it is not thick enough.
All were sized .309 before PC.
.309 on the left, .311 on the right.

[rancher1913]

shake and bake will look like that. if you want perfect coverage you need to spray but thats a big mess to do

[405grain]

They look fine. Load them up and see how they shoot.

[GregLaROCHE]

They look better after cooled.
However, after sizing to .309 it looks like it is not thick enough.
All were sized .309 before PC.
.309 on the left, .311 on the right.

They look like shake n bake boolits sometimes do. What are the dark marks on the ones on the left? Did the pc get rubbed off or is that lead residue from your sizing die?

[jdgabbard]

Look good to me. But, I'd bump up my temp. Generally you're going to want at least 400F to properly cure your PC. I personally run my oven at 415F. I let it preheat, stick my bullets in, and then start a time for 40 minutes to allow 10-15 minutes to get back to temp after opening the door and having the bullets sink some the heat from the system. That gives me a cure time of at least 25 minutes at 415.

Thats just my method. Whatever works for you should be good. I just like to make extra sure mine are cured properly. I used to work in the Powder Coating shop for Sundowner Trailers, and have seen how PC reacts to abuse when it hasn't been properly cured.

[hylander]

They look like shake n bake boolits sometimes do. What are the dark marks on the ones on the left? Did the pc get rubbed off or is that lead residue from your sizing die?

Rubbed off I'm guessing

I'll cook the next ones a bit hotter and longer

[jdgabbard]

The spots that look like bare lead won't actually be bare lead. PC wicks, and spreads polyester over the entire surface. It might look bare, but there is still PC over that part. It'll shoot fine with a few spots that look bare.

[hylander]

Just finished cooking another batch.
How long do you wait before sizing?

[crandall crank]

I was having some problems with temperature. I finally found a counter top sized convection oven/toaster. I re-wired it so the fan runs continually and the heater elements are controlled by a PID. The time starts when the temperature reaches the set point. I also place the coated bullets in the silicone ice cube trays. These two changes have solved many problems for me.

[shooter bob]

I tap the powder coated bullets against the container to knock off a little of the excess powder coat . Maybe give that a try. They look good to me. Bob

[popper]

Probably thick coating, try knocking off excess before cooking. Won't hurt anything. I starts from cold so they get proper 'flow' time. Too fast heating and PC doesn't flow completely before cross-linking. Once cross-linking starts, flow ceases.

[Land Owner]

For quicker heat recovery, put heat sinks (chunks of iron or steel) in the bottom of the oven. These sinks, once heated, will quickly bring the internal temp back after the door is opened.

[oley55]

Probably thick coating, try knocking off excess before cooking. Won't hurt anything. I starts from cold so they get proper 'flow' time. Too fast heating and PC doesn't flow completely before cross-linking. Once cross-linking starts, flow ceases.

interesting recommendation about temps. I have gone to some lengths adding heat sinks n what not so that I don't have a lengthy get to temp before starting my cook time clock. as is it takes my oven 5-8 minutes to recover to 400F before I set my timer. I'd think a too gradual/slow warm up would encounter the cross-linking you mentioned when the powder was getting near the proper cure temp. I mean it's not like our ovens are flash heating.

For what it's worth I have drilled and pinched thermocouples into most of my bullets so that I would know with certainty when the entire bullet reaches cure temp. After a lot of batches it seems 5 minutes is near dead on for any size bullet I cast. Accordingly I start my cook clock when the oven reaches 400F and add the 5 minutes. So I'm cooking my bullets for 25 minutes.

All that said I am by no means an expert and new to the PC game when compared to the PCing pioneers found here.

[jsizemore]

Just finished cooking another batch.
How long do you wait before sizing?

When I can pick them up with my bare hand. The sized portion will have a slick, shiny, polished appearance when the temp is right.

[405grain]

I generally size the uncoated bullets before powder coating them. If they are air cooled you can size them as soon as they're cool enough to touch, or months, or even years later if you like. If they are water quenched it will be different, and a whole other thread can be written on that subject. (especially if water quenched and powder coating is involved) I size the bullets prior to powder coating for two reasons. First, on several of my molds the PC will increase the diameter of the gas check shank, making it hard to install gas checks. In that case it's best to seat and crimp the gas check before doing the PC. Second, the bullets usually cast just a little bit oversize. Then the PC can add an additional .002" to the bullets diameter. By sizing both before and after powder coating I'm not putting too much stress on the bullet by trying to swage the diameter down so much all at one time.

An exception to this process is when I'm making bullets for a 7.65x53 rifle. For that I take the Lyman #311284 bullet and powder coat it before it's sized. With the as cast bullet, and the added thickness of the powder coat, I can size this bullet to .3125" and use what was a 30 caliber bullet for 7.65 (would probably work good for 7.7 Japanese and 303 British too)

[Land Owner]

If I don't like a coating, I coat them twice, and maybe change color. The sizing die takes care of the diameter.

[Joe K]

When sizing, I use a finger touch of Hornady unique case lube or the Lee case lube. Smear it on the side of a plastic bowl and swirl the boolits about a hundred. This helps go through the size die easier and helps eliminate scraping the pc. Those case lubes are non petroleum based and may be others it’s just what I have and use. Hope this helps.

[hermans]

Look good to me. But, I'd bump up my temp. Generally you're going to want at least 400F to properly cure your PC. I personally run my oven at 415F. I let it preheat, stick my bullets in, and then start a time for 40 minutes to allow 10-15 minutes to get back to temp after opening the door and having the bullets sink some the heat from the system. That gives me a cure time of at least 25 minutes at 415.

Thats just my method. Whatever works for you should be good. I just like to make extra sure mine are cured properly. I used to work in the Powder Coating shop for Sundowner Trailers, and have seen how PC reacts to abuse when it hasn't been properly cured.

This is very good advice, I use the same method and I have coated boolits that does not always look perfect, but they always shoot perfect.

[charlie b]

Those marks are just from the size die when that much difference in dia is made. They will shoot fine.

I am kind of a pick about it, but, I size my PC bullets before and after PC. One of my bullets I size body and nose, then PC, then size body and nose again. I have a lot of different dia sizer bushings

I preheat the oven but it does cool when the door is opened. Pre heat bullets for about 5min then bake temp for another 20min. And, yes, if I leave too much powder on them I can get 'runs' or 'orange peel'. I like using Smoke's Clear cause it seems to go on more evenly.