Any insight would be appreciated

[Toymaker]

My first powder coating was highly successful and worked out very well. They worked exceptionally well too. I was tickled pink …. actually red.

So I decided to give some bullets for the 45-70 a try. I did a quick casting of Lyman 457-193 (Beagled) in Lyman #2. These drop 0.460" as cast. I was guessing the PC would add 0.002" - 0.004" to the diameter and I would size them to 0.459". Everything worked out as expected.

I washed the bullets in acetone to get rid of any grease or oil that may have contaminated them. Probably unnecessary, but I felt better for doing it. I then put them out on a paper towel to dry for 30 minutes while I set up the oven and started it warming.

I use the Ziploc 2 cup twist top containers. Added 4 layers of black pellets from Smoke and two level tablespoons of his John Deere Green. To help with static I hold the container in a pair of military wool gloves. Swirl for 30 seconds; shake up and down for 30 seconds PLUS turn the container on its side and tumble for 60 turns while rubbing it with the gloves. When I opened the container I would grab the bullets with forceps, tap the forceps against the side of the container to get rid of excess powder and stand them up on the oven tray which had been covered with non-stick aluminum. I'd repeat until there were 50 bullets spaced in rows about an inch apart on the tray. I could probably crowd them more, but I'm still learning.

The oven thermometer is reading 400°F so I open the oven, put the thermometer on the tray with the bullets, slide the tray in and close the door. The temperature has, of course, dropped so I watch until it reaches 400°F again and then start a 20 minute cooking time. When they were done I turned off the oven, opened the door and let things cool down.

As I was putting the bullets through the sizer I noticed that the PC coverage seemed blotchy and thin in areas. After I was done I looked at each carefully and even found bare spots. I decided that I was going to re-coat.

Because the bullets had gone through the sizer I started with a good acetone wash to get rid of any residual lube that may have been in the sizing die. THEN, THIS TIME I put the bullets in the oven at 150°F for 30 minutes to pre-warm them AND get rid of any acetone. Then I went through the same coating and cooking process described above.

Half of the bullets came out with what I can only describe as "blisters". You can see them very clearly on the bullets sitting upright in the Styrofoam holder. At first I thought it might be due to acetone being trapped in the first coating. But 30 minutes at 150°F should have evaporated any acetone. The PC sticks, doesn't chip or flake. They just have blisters which will play havoc with the BC. (I guess a little sandpaper will smooth things out - my tongue is in my cheek).

Any ideas what happened? Thanks.

[Rcmaveric]

I dont wash with acetone. PC is basicly plastic and acetone eats plastic.

I woulf have just coated the second time and tossed them in.

Try tumbling without the BBs. Warm the bullets to the touch and then swirl. BBs make a thinner coat for me.

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[MyFlatline]

I only wash them if I think they got contaminated, try denatured Alcohol next time. For lube when sizing , try water. Dip your finger in a dish of water and roll the bullet in your fingers, it helps. I get blotches with JD green also ( not Smokes) but get a good coverage, as RCMav said, just coat them again if the look sparse.

[popper]

Use less powder. Lumps of PC that didn't get knocked off. PC flows ~200F but clumps don't have enough weight to flow down.

[sw282]

The bubbles are coming from acetone that didn't fully evaporate after you washed the boolits.. There are better/hotter thinners out there, but only available to professional painters..

[popper]

Acetone absorbs water, 150F gets rid of it but not all water. But tumbling should eliminate any water on the boolits but will cause clumps of PC. Acetone could have damaged the first coat but to cause pimples? Don't think so.
In reality, load em and shoot em. Won't make a bit of difference. I've done 30 cal with smoke's black, it tends to leave bumps to (black doesn't flow real well) and no difference in accuracy that I can see.

[Toymaker]

Rcmaveric, acetone eats some plastics, but not all. I didn't test the Green but I had tested the Red bullets for safety with acetone. After about 15 minutes it did begin to soften the Red PC. When I "washed" the Lyman 457-193 bullets both times it was quick, less than a minute. Into the acetone, swish, swish and pick them out to dry. Besides why only have of the bullets?
MyFlatline, I like your idea of using alcohol instead. I'll have to test and see if it needs to be rubbed or if just a couple of swishes will do the trick.
Popper, it didn't look lumpy. It was smooth except for the "pimples". I got out a magnifier and opened a couple. They weren't solid, they were hollow. I'm thinking you've got the answer with the water absorbed by the acetone. It boiled under the PC coating and raised a hollow "pimple". BUT, again, why only half of the bullets?
sw282, I think 150°F for 30 minutes is going to evaporate the acetone. Maybe not all the water absorbed by the acetone, but the acetone is gone. As for other solvents available only to professional painters …… I'm a chemist, retired but still a chemist with friends still in the labs.


THANKS EVERYONE. Your thoughts and ideas have gotten me started. I'm still wondering why only half of the bullets. But maybe I'll set up another test.

[sw282]

Being an industrial painter (retired) l can say MEK(methyl ethyl ketone) does a much better job as a solvent than acetone. Also SWP #54 and #58 Reducer do a great job as well. Acetone leaves a residue that lingers for around 12hrs...Heat accelerates its evap time considerably.. The other mentioned solvents evaporate MUCH faster.. No heat required

[Toymaker]

hmmmmm. I have MEK, and Methylene Chloride. I didn't think of it, or rather I did but made an association between the two and methylene chloride will REALLY eat plastic.
I need to make some more Lyman #2 since our weather has turned nice. I should take advantage of the weather and cast more bullets too. Then I'll be set for more testing

[Dragonheart]

I thought I would throw in a couple of comments. If you air cool your castings and don't handle them with bare hands then contamination will not be a problem so no additional cleaning is needed. If you are not getting uniform coverage then high humidity is the likely problem. Just preheat your castings to no more than 150 degrees. A good glass thermometer to monitor the temperature is needed, not one of these spring thermometers. As far as the oven cure time realize it is not the air temperature of the oven it is the surface temperature of the castings that needs to reach 400 degrees and maintain that temp for a minimum of 10 minutes, so total oven time will depend on how loaded the oven is. Give it another go and you will be a pro in no time.

[Toymaker]

Dragonheart, I do air cool and I only handle them to put them into the Styrofoam or plastic holder you can see in the picture. I do the PC in the basement, with a dehumidifier, but this has been the wettest year in recorded history here. My notes say when I did the red 38-55's it was a nice sunny day. When I did the green 45-70's we were in the middle of 5 days of rain. BINGO.
I'm going to test pre-heating. I think that's a good trick all the time, along with my wool gloves. I do use a spring thermometer, but there's a thermal probe from a multi-meter in there too. The oven has a "turbo" setting which starts a fan inside to move the air around for even heating which helps. Cook time doesn't start until the temperature reads 400°F so I'm confident everything is to temperature. It gets a solid 20 minutes by the clock, not the oven timer.
Bright sunny day but it's my day to practice at the range so I won't make any Lyman #2 alloy. Tomorrow it will still be nice and I'll do it then and make some bullets too. That gives me a couple of days to PC and let them "rest" to set the alloy crystal structure before loading and testing.
Love your location, Dragonheart. Been there several times. Up in LaGrange too. Beautiful area, unless you're allergic to cedar.

[Dragonheart]

Just a side note: All this worry about alloy mix is left over thinking when you lubed bullets with grease & wax. When the only thing providing resistance to torque spinup is the alloy and the only lubrication is grease it makes sense to be concerned about alloy.
However, when you properly PC you are in fact creating a hard jacket that bonds to and protects the alloy jus like any jacket. I have been shooting nothing but range lead for the last 6 years (when I started PC). I have tested PC range lead at 3500+ fps and pure lead at 1400 fps. with no leading. By the pressure tables this would be impossible with lubed alloy. By all means use what you have, but going to a lot of effort and expense to make #2 or whatever is not necessary for the needs of most. I do think a harder alloy is a benefit on full power rifle loads, but I can't say that is confirmed.

[GregLaROCHE]

I tried washing and soaking some lubed boolits in acetone twice, before putting them in the powder. Still the power wouldn’t coat right. I think a stronger solvent is needed. I wonder if brake cleaner is any better. I use it often for other cleaning jobs when reloading.

I am now extra careful not to get any greese or oil film on virgin boolits. I use throw away latex gloves when handling them. They cut down on chances of getting lead in your body too.

[Dragonheart]

I tried washing and soaking some lubed boolits in acetone twice, before putting them in the powder. Still the power wouldn’t coat right. I think a stronger solvent is needed. I wonder if brake cleaner is any better. I use it often for other cleaning jobs when reloading.

I am now extra careful not to get any greese or oil film on virgin boolits. I use throw away latex gloves when handling them. They cut down on chances of getting lead in your body too.

Heating the bullets to a high, but under the alloy melting point can burn off some contaminates, but obviously it is best to not let them get contaminated to begin with.

To ease your mind you have to ingest the lead for it to get into your body and do damage. Handling lead is not a problem other than you can transfer lead dust to where it could do harm.

[Forrest r]

I don't get the whole wash the bullets thing???

Haven't coated a lot of bullets, around 700# since 2013. But I've never washed anything.

I've cast bullets & air cooled, water dropped. Always hand sort them for defects. If the bullets are either over 3/1000th's of my target diameter or going to be 3/1000th's over my target diameter after pc'ing. I size the cast bullets 1st and then coat them (if needed) and re-size them to the target diameter. Anyway, I've never had a problem with hand "oils" on the cast bullets. Every bullet I cast/coat gets handled at least 2 times with my bare hands. Some of the last bullets I coated, it's what they typically look like. Never had an issue with water dropped bullets either, but I do make sure they are dry before I coat them

[IMG][/IMG]

Instead of all the washing you might simply try coating them.

[owejia]

Got some 32 cb in a trade used alcohol to wash lube off and coated using smoke's powder, got a good coat, also used alcohol to clean some 45 acp lubed Missouri cast bullets alcohol removed the blue hard lube and bullets coated fine. Alcohol not as toxic as acetone. Have always used my bare hands to handle cast boolits and never had any problems, always got excellent coverage with Smoke's powder

[GregLaROCHE]

I don't get the whole wash the bullets thing???

Haven't coated a lot of bullets, around 700# since 2013. But I've never washed anything.

I've cast bullets & air cooled, water dropped. Always hand sort them for defects. If the bullets are either over 3/1000th's of my target diameter or going to be 3/1000th's over my target diameter after pc'ing. I size the cast bullets 1st and then coat them (if needed) and re-size them to the target diameter. Anyway, I've never had a problem with hand "oils" on the cast bullets. Every bullet I cast/coat gets handled at least 2 times with my bare hands. Some of the last bullets I coated, it's what they typically look like. Never had an issue with water dropped bullets either, but I do make sure they are dry before I coat them

[IMG][/IMG]

Instead of all the washing you might simply try coating them.

The washing was just for boolits that had been lubed before to be shot as greesers. I changed my mind after discovering PC and wanted to PC the boolits. I thought it would be easy to degreese with acetone, but it wasn’t .

[Dragonheart]

I removed the lube from several thousand bullets when I first got into PC back in 2012. I soaked them all in gasoline overnight, repeated the process then a final wash in acetone to remove the residual oil. After that they coated without problems.

[Smoke4320]

The blisters are caused by outgassing of the acetone.
My suggestion is after washing in any chemical wait at least 30 minutes. Then dry in the oven at no more than 140 degrees for 30 minutes. After that you should have clean and dry bullets and no outgassing