A partnership for powdercoating.

[blarby]

430, 240g 1 coat. Sized.

There was significant shearing on greater than 20% of the bullets that had only one coat during sizing, irregardless of their cosmetically appealing quality.

For this reason, 2 coats, cured independently, will be used from this point forward, until something better pops up ~

 

[LiveLife]

... one exception- a 5' drag across my carpet for more residual static charge.

Yes, I am glad you remembered that trick to increase the static electricity.

(What blarby meant is rubbing or dragging the plastic container on the carpet.)

 

[Havok7416]

A piece of scrap carpet mounted on the bench might help instead of crawling all over the floor. Perhaps Blarby is already doing that though.

 

[LiveLife]

Sized 401, 1705gr TL

There was no shearing of the coating during sizing, and they sized very easily on the lee push through.

Were they baked once or twice before sizing? What was the humidity level?

Already my desire to use the LLA tumble method is fading.

Old dogs learning new tricks.

A piece of scrap carpet mounted on the bench might help instead of crawling all over the floor.

See what I mean about networking and sharing information? That's a great idea!

 

[Pelo801]

Could you mic a a bullet pre PC and then mic same bullet post PC? I'm curious how much diameter the PC adds to the bullet.
Thanks in advance.

 

[blarby]

Were they baked once or twice before sizing? What was the humidity level?

They were baked twice before sizing.

Oddly enough, my guess for the ambient humidity in my area was correct- 50%.


Your .309's are on their second trip through the oven, BDS.

 

[blarby]

Unfortunately, someone came stomping up the stairs in the middle of that second coat curing, BDS.

about 15-20% of the .309's were ejected from the holes, and cured on their sides. I didn't interrupt the process as I wanted the ones that stayed upright to finish.

They are cooling now.

 

[blarby]

On the next batch of .401's , I am going to try a version of the "massaging" the bullets, by rolling them between my gloved fingers on the bearing surfaces as I place them on the tray.

Maybe we can get this one coat process to work better. Time will tell.

 

[blarby]

Your lipsticks....

 

[LiveLife]

They were baked twice before sizing.

Oddly enough, my guess for the ambient humidity in my area was correct- 50%

On the next batch of .401's , I am going to try a version of the "massaging" the bullets, by rolling them between my gloved fingers on the bearing surfaces as I place them on the tray.

Maybe we can get this one coat process to work better. Time will tell.

I was going to suggest if higher humidity isn't allowing thick enough coating to try the plastic/ziplock bag method and picking out the coated bullets using gloves dipped in powder coating but looks like you already got it handled.

Your .309's are on their second trip through the oven, BDS.

Unfortunately, someone came stomping up the stairs in the middle of that second coat curing ... about 15-20% of the .309's were ejected from the holes, and cured on their sides. I didn't interrupt the process as I wanted the ones that stayed upright to finish.

Hey, life happens. If they size well enough, send them separately in plastic cling wrap and I will test them to see how "blem" PC bullets shoot.

 

[blarby]

These are the 401's that were "roll coated" or "massaged" between my fingers as I placed them on the tray.

There are a few that have extremely thin spots, but for the most part are remarkably uniform along the driving bands.


Sizing to come, we'll see.

BDS- I tried your .309's using this method. They are in the oven.


This is shaping up to be a long day !

 

[blarby]

Ok, a moment of amusement.

I'm not posting a pic of it, as someone would assuredly say I was abusing my cats.... however....

MAke a mental picture of this;

A large white and red and black cat, its entire head fully within a yogurt container full of powdercoating paint.... removes its head and yawns.

Full red, and can't tell *** is going on.

Small delay to shower the kitty........

 

[LiveLife]

Those bullets are looking good.

So those in higher humidity areas can powder coat with success using the plastic/ziplock bag method.

Nice.

... black cat, its entire head fully within a yogurt container full of powdercoating paint ... Full red, and can't tell *** is going on

Ooops!

 

[blarby]

These are the 401's that were "rollcoated" only once, after sizing.

There is significantly less shearing- perhaps 5%, perhaps less.

However, they are remarkably uniform, and the parts that sheared were in areas that were noticeably thin before sizing- so I attribute that to my failure in application- not the coating itself.


In crappy news, the point down method fails again- this time, a large number apparently got too hot for too long at the point of the bullet, and the weight of the bullet ... broke itself.

Some survied, but not many.

We need another method for those- lets work on it.

 

[LiveLife]

Could you mic a a bullet pre PC and then mic same bullet post PC? I'm curious how much diameter the PC adds to the bullet.

I think once blarby settles down on a method that produces consistently thick enough one coating, he'll probably measure the thickness of the coating.

Some have posted PC thickness at .001" - .0015" so I am curious too.

 

[LiveLife]

These are the 401's that were "rollcoated" only once, after sizing.

There is significantly less shearing- perhaps 5%, perhaps less.

However, they are remarkably uniform, and the parts that sheared were in areas that were noticeably thin before sizing- so I attribute that to my failure in application- not the coating itself.

Wow, they are looking good for one coating. I think some using the plastic bag method posted that they "massage" the bullets with BBs and as the bullets are coated, they pick them out using nitrile gloves dipped in powder. I think powder coverage will improve with practice.

In crappy news, the point down method fails again- this time, a large number apparently got too hot for too long at the point of the bullet, and the weight of the bullet ... broke itself.

Some survied, but not many.

We need another method for those- lets work on it.

Many posted success baking Harbor Freight red powder at lower 350-375F at shorter time around 10-15 minutes (instead of 400F at 20 minutes). Perhaps, try at lower/shorter bake temp/time?

You are doing good powder coating for the first time! Hang in there.

 

[LiveLife]

I know you have a lot on your "hot" plate ...

Could you water quench a batch of .309" bullets from the oven so I can do a comparison between the two?

Thanks!

 

[blarby]

I think once blarby settles down on a method that produces consistently thick enough one coating, he'll probably measure the thickness of the coating.

Last two batches of .401 have come out sized at....401, after one coat.

The double coated ones are also coming in at .401, although they are a tumble lube design. This is what I expected from a push through sizing, although I will measure them for bounce back in the morning.

Most of them dropped right at .400, although some of them dropped at .401 from the mould, after quenching.

 

[blarby]

Ok, I measured the .401's this morning. The handful I grabbed last night has popped back to .4015

I measured the .430's this morning, and they have popped back to .4305.


These bullets had lain a full week in buckets after casting. For whatever that is worth.

 

[LiveLife]

The double coated ones are also coming in at .401, although they are a tumble lube design. This is what I expected from a push through sizing, although I will measure them for bounce back in the morning.

Most of them dropped right at .400, although some of them dropped at .401 from the mould, after quenching.

I thought water quenching would shrink the bullet but castboolits threads indicate depending on the hardness of the lead alloy, water quenching may increase bullet size. Learn something new everyday.

As long as bullets are sizing around .401" after coating/baking, they should work well?

 

[LiveLife]

Ok, I measured the .401's this morning. The handful I grabbed last night has popped back to .4015

I measured the .430's this morning, and they have popped back to .4305.

So the sizing changed after PC baking and resizing?

If the .4015" bullets are resized now, would they stay at .401"? Chances are .4015" bullets would fit the chambers of Glock/M&P but the tighter chambers of Lone Wolf will not accomodate bullets larger than .401". A point to note but since the powder coated bullets were meant to be used with factory barrels, it may be OK in the end.

Since I don't cast, don't know much about alloy characteristics soon after being casted/heated/cooled/sized, etc.

Obviously more to powder coating and baking cast bullets than I originally thought.

 

[blarby]

Springback in sizing is something that die makers account for.

This happens all the time when people size bullets and say they are "undersized".

Apparently the PC "springsback" a little more than lead.


About the only thing I could think of if you couldn't use .4015 would be a .400 sizer... looks like you'd end up at .4005.

One thing I can say about this coating- its got some "give". Getting it to go from .4015 to .4000 is not hard at all.

Those of you who have ever measured taper crimp correctly and tried to "wish" it into spec using more pressure on the caliper know exactly what I mean.

if the .4015" bullets are resized now, would they stay at .401"

I'm not sure- but I will try. My gut says no, but this is a new material for me....anything is possible.

Some have posted PC thickness at .001" - .0015" so I am curious too.

That seems to hold, even with multiple (2) coats.

 

[blarby]

The .358's turned out real good, coat wise.

One coat, rolling the bearing surfaces.

 

[blarby]

Wow, ok, just found out something very interesting.

Apparently, humidity REALLY matters in adhesion.

Yesterday, we were at 50%. Everything looked good, minor rolling about to redistribute lube.

Today we are at 70%, and I get this :

 

[blarby]

However, a few rolls around on the carpet to pick up extra static and we get this :




A major bonus in adhesion.