powder coat scratches off with fingernail

I shouldn't be able to scratch off the powder coat from a boolit with my finger nail right?

i'm using Smokes John Deere green in a case tumbler to coat the boolits. then it's on to the toaster over for 20 minutes at 400 degrees.(I don't have a thermometer so I can't be 100 percent sure the temp is right) the finished boolits look good but I can scratch the powder coating off with my finger nail and i'm getting serious leading when I shoot them. what am I doing wrong?


little more info just in case it's necessary.

boolits are cast from range lead and water dropped. I don't know how hard they are. boolits are the 429421, lee 452 300, NOE 360 180 wfn, and a custom Todd Corder 312-120 fngc mold. none of my loads are over 1300 fps. the 360-180 and 312-120 boolits are sized for the cylinder throats and the 429421 and lee 452-300 are shot as cast/coated because they come out just right for my guns.

No you should not be able to scratch off the powder coat. Is there any way they got contaminated with oil, grease or silicone?

I don't believe so. they usually go from the mold to the water bucket, then onto some paper towels to dry and then into the tumbler for powder coating.

to be certain I could clean some uncoated boolits with alcohol and then try and coat them.

Check your oven temperature with an oven thermometer.

+1 on put an oven thermometer in the middle of the shelf you bake your bullets on and determine what temperature your oven needs to be set at for the thermometer to reach 400 degrees then make sure your oven is set at that temperature for baking

It doesn't make sense to quench your bullets if you are going to PC them, Quench after you PC.

when's the last time you changed the water and cleaned your quench bucket.

How thick is the PC on the bullets before baking? did you shake / knock off all the excess powder?

Are you pre-heating your oven?

You'll be happier and have better results with a convection oven (I just found a good Oster at goodwill for $20)

New in store around $50 even new you'll have to check the temperature, almost all are off some are way off.

Make sure there's no residual moisture from water dropping. I had that happen & got the results you describe. I now put them in a convection oven at the lowest heat setting to get them warmed up to the touch & evaporate any remaining moisture, then I powder coat them & haven't had any problems. Also, has the humidity been high? That might be a factor as well.

I second the no more water quenching. If you powder coat it is not really necessary .

Before applying the powder have them into a plastic container and squirt a bit of Acetone and shake them well for 30-40 seconds. Dump them on a wire mesh tray and have them in front of a fan to dry. After that do not touch any of them with your hands.
Also every thing mentioned in the above posts is important.

I water drop all my cast boolits. After retrieving them from the bucket, place on a tray to dry for a day or two. I then proceed to PC dry tumble method with blk air soft pellets. No problems.
i think you need to check your oven tempture!
My 2 cents.

Only time I had an issue was when one element burnt out of the toaster over. My bet is on Temperature.

well I water drop because I find it quicker/easier for me. I know that time in the oven softens the boolits.

I change the water out with fresh well water every time I cast.

there seems to be plenty of powder on the boolits, extra powder is knocked off.

I do pre heat the oven. and I make sure the boolits are dry before tossing them in the tumbler.

i'll try cleaning them with Acetone and see about getting a thermometer for the oven. till then I may play around with the temp and see what happens. the oven only goes to 450 so that shouldn't take long lol.

cook them longer.
your obviously not up to the full 400, so just add some more time.
the powder will cure at 375 it just takes longer.

Well water?

That could be the problem. Is your well water high in iron or other minerals?

Sometimes the oils on your hand will cause areas touched to not bond as well as others. I use nitril gloves from HF after casting till bullets are powder coated.

Try cooking for 30 minutes rather than 20. You also might be trying to cook too many boolits at a time. Cheap convection ovens have a limit to how many boolits they can get up to temperature.

oven thermometers can be had a wally world for around $5

in cooking section

well worth the investment

most ovens' on-board dials aren't anywhere close to what's indicated

You really have to know the temperature of your oven, without a thermometer you are just guessing. I found mine to be 50F off and it is a fairly expensive convection.

I think your oven temp is off. I can't scratch PC off with a thumbnail. Bake at 400 for 15m max. My oven set at 400 only gives about 375, so check it with an oven therm, like $6 at Wally.

looks like it might be the oven temp. cranked it all the way up and got some good bullets. thanks all!