Swaging Powder coat 40 S&W with Lee sizing die produces multiple sizes bullets

[rjallen]

Title says it all. I used a Lee APP press with the sizing die on the bottom with nose first sizing.
Some of the boolits size to .401 but I am getting .4015 even .402+ This my first casting & powder coating. All are from the same lead melt. I used 5lb Lyman#2, 5lb Linotype plus 2.5 lb pure lead. Used the "shake & bake" method for the powder coating using Eastwood Ruby Red & Ford Light Blue. I got great coverage and I quenched in water right out of the toaster oven.
I did note a very few boolits had the coating damaged during sizing that resulted in small chips of powder coat flaking off. I also discovered the underside of these flakes had a skin of lead. In other words the flake did bond to the lead properly I believe.
I attempted to resize but each round stayed the same.

Looking for more experienced counsel.

I see that NOE has dies that work with Lee. Are these more accurate? Common sense tells me if you force a softer material through a fixed diameter hole of a stronger material the resulting product will ALL be the same diameter.

Thanks in advance

[rjallen]

I am not sure why this message was moved. My primary point of this post was to ask for assistance with sizing bullets to the point I found a variance of over 2 thousands in the bullet diameter. The larger sized rounds require the case mouths be enlarged, the bullet feeder has issues feeding these large rounds. This is the first time I have sized cast bullets. I cannot understand why I am getting varied sizes out of the same Lee Bullet sizer die. Perhaps this is "normal"
Again, I ask for guidance from more experienced reloaders of cast bullet. I mentioned I was powder coating these rounds and this message was moved to this space.
Thanks in advance.

[charlie b]

I suspect what you are seeing is the effect of the powder coat. If you were not careful when coating the thickness can be different between bullets, especially with the S&B method.

Test this. Measure your bullets before sizing. Coat them. Measure again. Size them. Measure again.

One thing with powder coat is it has a lot of 'spring'. If the coating is thicker then your bullet will probably be a bit larger than the die.

[rjallen]

Thanks Charlie
I thought the PC might be the culprit as it does seem to "spring" back. I might have to alter my technique as I noted there seems to be a slight amount of powder coat color formed around the bullet base- formed during the heat flow in the oven. Perhaps I am getting too thick of a coating.
After doing the swirling shake, I just pick up the bullet and tap it on the side of the plastic tub. I know many just dump the pc bullets on a wire grid then shake the bullets. Perhaps that will remove more excess powder? There is always a learning curve and I really want to hear from all of you that have preceded me down this road.
Thanks again

[charlie b]

YW

That 'ring' at the base is a good indicator of too much powder.

When I do a S&B I open the lid and then 'stir' it with the tweezers. That kinda knocks off extra powder before I pluck them to place on the pan. And, yes, I use the black BB's in the tub. I like how they work. I usually shake about 30 bullets at a time in a 1qt container.

Forgot, I also 'wipe' the base of each bullet on a piece of cloth as well before placing on the pan.

FWIW, this is a good guide to S&B
https://www.mp-molds.com/tipstricks/...ble-dt-method/

[hornetguy]

I've never seen that much variation in bullets after sizing them... the only time I get variance is when the bullets are under sized for the sizer die.
The die should squeeze everything, PC and lead down to the size of the die. If the die is .402, and your cast, pc'd bullets are not at least .402, then you will see variations.

PC flaking off is not a good sign. It should bond almost permanently to the lead, if cured properly.

What technique do you use? Do you use bb's with the bullets? If you do that, and only use about a half-teaspoon of powder for every 50 bullets or so, and use the swirling (centrifuge) technique with some tumbling (end over end) every 10 seconds or so, followed by more swirling, you should get a pretty even coating.
Then, dump them into a screen of some kind, and lightly bounce them a little bit, that should do it... tweezer them onto your baking pan, and bring them up to about 400 deg at a moderate rate of temp increase.. once they get close to 400, set the timer for about 20 min or so.

[rjallen]

charlie
I already suspected my PC was a tad too thick. I know, as a beginner, I was worried about coverage. I will experiment with your techniques. What do you use as a "no stick" bottom cover. I used those latex baking mats for my first attempts I also want to try the no stick aluminum foil- I am standing up each bullet and don't worry about the extra effort. I am also quenching out of oven. If nothing else it cools off the bullets quickly and ends the possibility of burning fingers.

[rjallen]

I've never seen that much variation in bullets after sizing them... the only time I get variance is when the bullets are under sized for the sizer die.
The die should squeeze everything, PC and lead down to the size of the die. If the die is .402, and your cast, pc'd bullets are not at least .402, then you will see variations.

PC flaking off is not a good sign. It should bond almost permanently to the lead, if cured properly.

What technique do you use? Do you use bb's with the bullets? If you do that, and only use about a half-teaspoon of powder for every 50 bullets or so, and use the swirling (centrifuge) technique with some tumbling (end over end) every 10 seconds or so, followed by more swirling, you should get a pretty even coating.
Then, dump them into a screen of some kind, and lightly bounce them a little bit, that should do it... tweezer them onto your baking pan, and bring them up to about 400 deg at a moderate rate of temp increase.. once they get close to 400, set the timer for about 20 min or so.

One my second and third efforts, producing approx 250 40 S&W and 25 45/70, I got only 3 40 S&W with chips and only after sizing. My first batch, which I think had temp. issues had 20 bullets with multiple types of issue before I sized. The strange thing- you guys may see this all the time- but I noted in almost every case the chips showed a layer of lead on the underside. So the PC did adhere to lead. But obviously not enough.
hornetguy:
hrnetguy:

The 40 S&W were produced from two different Lee dies. One seemed to have a greater size range. The dies are supposed to make .401 bullets and it appears I may have cavities with slightly different sizes. Is this common?
I use the Shake & Bake using a #5 plastic tub. Eastwood powders. Was amazed how quickly the bullets were coated and I may have continued too long. As I already said most had no problems other than perhaps too thick of a coat and I think- really only a guess, that has something to do with the size issues. I am not using any type of BBs although I considered it. Maybe the BBs would knock off excess powder? I only considered their need if I had coverage issues. I am blessed to live in Montana and I can PC when the humidity is low. Again, I was amazed how quickly the "shake" happened, especially after watching all those YouTube videos. I did the shake my hand using the technique as you describe-except for the BBs.
I am still playing with toaster oven. I have ordered an oven thermometer. I have an remote temp gun but I am not getting temps anywhere close to 400 focusing the gun on the oven walls whether I try to aim the gun through new clean glass or open the door and let the heat out. You make a good point: focusing on the BULLETS. I still need to work with this oven.
I also want to try using a screen to separate the excess PC as you mentioned. I think I have been overly concerned about disturbing the coating. Thanks for the good advice!

[hornetguy]

The 40 S&W were produced from two different Lee dies. One seemed to have a greater size range. The dies are supposed to make .401 bullets and it appears I may have cavities with slightly different sizes. Is this common?

It probably happens more times than it should. I haven't had any issues to speak of, but I have heard others have....

I am still playing with toaster oven. I have ordered an oven thermometer. I have an remote temp gun but I am not getting temps anywhere close to 400 focusing the gun on the oven walls whether I try to aim the gun through new clean glass or open the door and let the heat out. You make a good point: focusing on the BULLETS. I still need to work with this oven.

I just bought a $10 oven thermometer at Wallyworld.... it seems to work pretty well. I have heard that others have found that the IR thermometer guns are not accurate enough or consistent enough for verifying the toaster oven.
I also am of the opinion it's easy to overthink this. If you bought two of the Wallyworld thermometers and compared the two against each other, that should be adequate. My PC is probably never exactly 400 degrees... I think that anywhere within 10-15 degrees either way is probably ok. Just my opinion... worth what you paid for it.

[popper]

nose first sizing. That is the problem.

[reddog81]

I try to get as thin a coat as possible with PC. I shake off as much as possible using a colander. The most important thing is to get the PC and lead up to the correct temp. If PC is flaking off going through the sizing die that is an issue. I’d guess fixing the problem with curing the PC correctly might fix the other problem.

[rjallen]

nose first sizing. That is the problem.

Okay......why?

[garandsrus]

Most people probably size coated bullets nose first! It works fine….

[414gates]

You're probably reading the sizing with a vernier.

Check size with a micrometer.

[BRatigan]

I found a similar chipping of the powder coat with lead adhered to the chip and discovered that a frosted bullet allows this to happen. Possibly too hot of a mold when casting. The underside when magnified should show a granular appearance to the lead on the chip. Not sure about the inconsistency of the sizing. Other folks here are better at that.

[charlie b]

charlie
I already suspected my PC was a tad too thick. I know, as a beginner, I was worried about coverage. I will experiment with your techniques. What do you use as a "no stick" bottom cover. I used those latex baking mats for my first attempts I also want to try the no stick aluminum foil- I am standing up each bullet and don't worry about the extra effort. I am also quenching out of oven. If nothing else it cools off the bullets quickly and ends the possibility of burning fingers.

I use one of the silicone baking sheets cut to fit the bottom of the pan. I did the non-stick Al foil for a while but got tired of it. Some bullets would still stick to it, then it wrinkles, etc.

This is what I use for a pan. The grid keeps the bullets from falling over like dominos. I don't water quench, but, I use Lyman #2 alloy so my bullets are around 16bhn without heat treating. Enough for over 2400fps. Left is 210gn .308 Smoke's red, right is 104gn 6mm Smoke's clear. And, yes, a fairly thin coat works fine.



PS just use a std oven thermometer to check your over setting. Once you have a stable 400F then mark the oven dial (or just don't move it). Mine is a digital readout and 370F on the readout gets me 400F in the oven.

[rjallen]

I found a similar chipping of the powder coat with lead adhered to the chip and discovered that a frosted bullet allows this to happen. Possibly too hot of a mold when casting. The underside when magnified should show a granular appearance to the lead on the chip. Not sure about the inconsistency of the sizing. Other folks here are better at that.

Thanks, will follow up on your advice.

[popper]

nose first sizing. That is the problem

my bad, mind read it wrong, thinking base first.
I've had some problem with scraping PC off when nose first, pushes all the excess Pb down to the base where the diameter increase causes pressure increase and PC looses. IMHO the PC stretches so it moves with the Pb. Gets thinner and fails. Harder alloy makes it worse.
Frosted A/C alloy has a thin layer of Sb on the outside that is weaker. During cooling, higher melt temp metal 'freezes' first and that occurs on the outside. The cooling process for 'alloy' has a changing % of metal, high Sb, then low Sb, repeat. High Sb on the outside 'freezes' and is 'stuck' there.
High Sb alloy has more springback to sizing. IMHO, don't worry about it.
One good reason to add Cu to alloy! Cu locks up Sb in a real alloy, where normally Sb/Pb is a mixture.
Your alloy is ~7/4/89, BHN 16 A/C but much harder W/D from oven. Cut it with another 50% Pb, PC and then W/D for 40sw. My plinking alloy for 40sw is 2% Sb with pure. Works fine @ 950 fps.

[rjallen]

my bad, mind read it wrong, thinking base first.
I've had some problem with scraping PC off when nose first, pushes all the excess Pb down to the base where the diameter increase causes pressure increase and PC looses. IMHO the PC stretches so it moves with the Pb. Gets thinner and fails. Harder alloy makes it worse.
Frosted A/C alloy has a thin layer of Sb on the outside that is weaker. During cooling, higher melt temp metal 'freezes' first and that occurs on the outside. The cooling process for 'alloy' has a changing % of metal, high Sb, then low Sb, repeat. High Sb on the outside 'freezes' and is 'stuck' there.
High Sb alloy has more springback to sizing. IMHO, don't worry about it.
One good reason to add Cu to alloy! Cu locks up Sb in a real alloy, where normally Sb/Pb is a mixture.
Your alloy is ~7/4/89, BHN 16 A/C but much harder W/D from oven. Cut it with another 50% Pb, PC and then W/D for 40sw. My plinking alloy for 40sw is 2% Sb with pure. Works fine @ 950 fps.

Thanks for the explanation and the advice. I know the alloy used was harder than necessary, especially for causal target shooting.

[hornetguy]

I also tried the non stick foil, and had less than stellar results. I tried oven parchment paper, and haven't had a bullet stick to it yet. It lasts usually at least 3 cycles before it gets sort of brittle. It will turn brown, but still works for the 3 cycles. It might go 4.... it's still pretty cost effective, and it works.