first try powder coating.

[R.Newman]

I have been casting bullets for a while now mostly for black powder loads. I casted some bullets for my .44 mag. and thought I would try PC, didn't go well. Some of the bullets seem to have melted. I don't know if my alloy is bad or my oven was to hot. Any thoughts?https://uploads.tapatalk-cdn.com/20201005/ea7711b5dfe019060dad7dadd7ca1dc1.jpg

Sent from my SM-G935V using Tapatalk

[Txcowboy52]

I would start by checking your oven temperature. I personally have never seen that before.

[Conditor22]

Countertop ovens have the WORST thermostats!!!! I've seen Countertop ovens off 50-75° .

I've also seen (and made) little PC'd puddles before I upgraded to convection type ovens.

On the other hand, you powdercoating job looks great for the first time out.

put an oven thermometer on the shelf you bake on and adjust the temperature setting until it (they) read 400°
https://i.imgur.com/L9jYQck.png

** I found this oven for $15 at a thrift store :) **

My guess is that was baked in an oven that didn't have a convection setting (air circulating fan that evenly distributes the heat)

You can just melt down PC'd boolits and start over.

Show us your results after you get the oven setting figured out :)

side note, harder alloys melt at a lower temperature.

[mehavey]

Get one of these:
https://www.amazon.com/ThermoPro-Wireless-Digital-Cooking-Thermometer/dp/B01GE77QT0/ref=sxin_9?ascsubtag=amzn1.osa.ab0a5b83-d821-410d-a670-2e668689b072.ATVPDKIKX0DER.en_US&creativeASIN=B01GE77QT0&cv_ct_cx=Temperature+Probe&cv_ct_id=amzn1.osa.ab0a5b83-d821-410d-a670-2e668689b072.ATVPDKIKX0DER.en_US&cv_ct_pg=search&cv_ct_wn=osp-single-source-gl-ranking&dchild=1&keywords=Temperature+Probe&linkCode=oas&pd_rd_i=B01GE77QT0&pd_rd_r=f4e60060-c03e-4564-aedc-81785d399537&pd_rd_w=OA1v6&pd_rd_wg=536Cx&pf_rd_p=26c7e498-3189-4918-a321-ec25e32964ce&pf_rd_r=BTB1GNE11TEHC7PS8XTX&qid=1601861036&sr=1-1-d9dc7690-f7e1-44eb-ad06-aebbef559a37&tag=heavy0013-20

Put both probes in the oven at your PC location.

- Watch for the oven overshoot (may hit as high as 540 before the oven's thermocouples get control).
- Wait for the oven to stabilize (at whatever temperature it finally decides to associate w/ your dial)
- Adjust the dial to hit 400-ish (Mark it)
- Put the bullets in and watch the oven temp drop
- Then watch it rise/overshoot again (a bit -- 420 isn't going to hurt anything) adjust by cracking door for a few seconds.
- Learn the oven's idiosyncrasies and work with them. (Helps w/ food too)

[Hick]

Do like Mehavey says and you should be fine. Get in the habit of always PC'ing the same number of bullets each time (I do 50) and using the same setup (tray or whatever), and once you learn the tendencies of your oven, you will be able to just set it and go and they will come out the same every time. Your goal is to make it so that the things the oven has to heat are about the same every time. Doesn't have to be exact. For example, I use all the same settings for 50 bullets all the way from 100 grains to about 180 grains, but I always use the same heating tray and same quantity of 50 (I use 50 because I like to stand them on their bases, and my heating tray holds 50 nicely).

[slide]

That is a nice setup. Another option and cheaper is a digital thermometer with a thermocouple. Drill a hole in a coated bullet. Secure the thermocouple with high heat aluminum tape or pinch the base of the bullet(not my idea but a good one) in a vise. This way you are measuring the temp of the bullets and not the air temp. Read the instructions on your powder. For instance if it says pmt 400F for 10 minutes. This means the bullets need to reach 400F and stay there for 10 minutes. The other fellas are right. You will learn your oven. Later on you might want to add a PID. This is very easy so don't be afraid of it.

[bangerjim]

Agree. Buy a GOOD oven thermometer. Those cheeeeeep non-convection ovens can be off by as much as 40F from the dial setting!

But I have NEVER seen cast boolits melted like that! Way too hot.

My big cavity Oster digital convection oven holds the temp to ~4F around the cavity. Convection is the key to good baked boolits.

Nice thing about casting your own.............mistakes re-melt very easy!!!!!!!!!

banger

[cwlongshot]

I agree with all previous comments!

Its most likely oven temp these cheapos aint too accurate. :bigsmyl2:

Good thermo fixes that! My first was EXACTLY same!! :violin:

I have a few videos posted if ya would like to see my process.

CW

[hickfu]

I also have 2 Thermometers and preheat the oven with both, When they say 400, I take them out and put the bullets in and watch until the powder starts to melt and then start the 20 minute clock.

I just picked up another convection oven at the Thrift store today for 25.00 (it was also a rotisserie but those parts were missing, hence the 25.00 price) I did a test of the temp..... I put it on 400 and put in my thermometers and came back in 20 or so minutes, The heat was almost at 500* Tomorrow I will have to see where to set it for it to be 400*

[Tripplebeards]

What ever you set your temp at turn it down. Don’t feel bad. My first try was three years ago and I melted my boolits. After some good advise here....on buying quality powder from smoke my problems were solved. I was bumping my oven temp to try and get HF red to flow. They only thing that flowed was my lead till I bough done quality PC. Looks like your PC coverage is nice and even but you just got your oven to hot. I still have yet to buy a thermometer. The oven in my house is off because I bake my bullets of the 465° for 20 minutes and I get no boolit slumps or melting. I can go at 400° in my little toaster oven and be fine as well.

[gnappi]

I also have 2 Thermometers and preheat the oven with both, When they say 400, I take them out and put the bullets in and watch until the powder starts to melt and then start the 20 minute clock.

I just picked up another convection oven at the Thrift store today for 25.00 (it was also a rotisserie but those parts were missing, hence the 25.00 price) I did a test of the temp..... I put it on 400 and put in my thermometers and came back in 20 or so minutes, The heat was almost at 500* Tomorrow I will have to see where to set it for it to be 400*

I do the same thing, wait for the melt and set it to 20 minutes, it works. Thrift stores supplied me with both of my ovens, the latest a two tier convection for $6 and it holds 550 bullets. I had to search a bit and mod others to get four usable trays, but two loads (1100 bullets) and I'm done for the day.

Though I'm surprised that some ovens can get so hot at 1500 watts/ 110 volts to melt lead. I have yet to see a counter top oven have a setting higher than 450. I don't think I'd use an oven that could runaway it's set point.

[mehavey]

don't think I'd use an oven that could runaway it's set point.It doesn't "run away" so much as the sensors not get control until the oven equilibrates.
Initial overshoot can be as much as 160-180 degrees.

From an earlier post:

https://i.postimg.cc/sDfVvStr/Hamilton-Beach-EZ-Reach-Set-Up-Powder-Coat.jpg

[gnappi]

Imagine the throttle in your car goes from 65 to over 100 before you can gain control, "I" certainly would not call that overshoot. Overshoot is when your car accelerates to go up a steep hill and accelerates at the crest and on the down slope but you HAVE control. If any oven I owned went one hundred and eighty degrees beyond set point and I'd have it in the garbage... or the thrift shop YMMV :-)

I ran many million dollars worth of ovens in a thermal lab in IBM, if any of them were that unreliable they'd be off to repair.

[mehavey]

No... it's overshoot (or call it what you may) due to the bullet probe being above the heating elements (where the bullets are),
in contrast to the oven sensors being in the side panels. That space/panel environment takes time to equilibrate.
(And $65 does not a lab-grade oven make. Try it in any oven)

And rather than throwing it away, I just added one of a certain member's (very nice) PID controllers, wait 8 minutes for things
to settle down while prepping the projos, and watch a very steady ±1° settle in.

(It's called "Make Dubh" Scottish Engineering) :kidding:

[mehavey]

Postscript: THIS (https://www.amazon.com/Breville-BOV670BSS-Compact-Convection-Stainless/dp/B08DDJ9GG4/ref=asc_df_B08DDJ9GG4/?tag=hyprod-20&linkCode=df0&hvadid=459585790688&hvpos=&hvnetw=g&hvrand=7377066830722483974&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008148&hvtargid=pla-967621356891&psc=1) oven (my wife's digital*) had only a 5° overshoot, and held ±2°.
(Did I mention my wife's ?)

Just $200 out the door :bigsmyl2:











* ps: Digitals hate PID controllers

[gnappi]

Postscript: THIS (https://www.amazon.com/Breville-BOV670BSS-Compact-Convection-Stainless/dp/B08DDJ9GG4/ref=asc_df_B08DDJ9GG4/?tag=hyprod-20&linkCode=df0&hvadid=459585790688&hvpos=&hvnetw=g&hvrand=7377066830722483974&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008148&hvtargid=pla-967621356891&psc=1) oven (my wife's digital*) had only a 5° overshoot, and held ±2°.
(Did I mention my wife's ?)

Just $200 out the door :bigsmyl2:











* ps: Digitals hate PID controllers

Yeah, mine has ZERO of whatever you want to call it, but it takes a while to get there.

[mehavey]

mine has ZERO....What was it, and what did it cost?
Jus' wundrin.....

[gnappi]

It's a Hamilton Beach "Easy Reach" convection, it has a sliding top like a motorcycle face shield and two tray levels. Cost was five or six bucks in a thrift store. My backup oven was another thrift store buy and is a single level and it was in the same price range. It also gets to 400 a bit slowly but I have to put it on 450 to get there and it does not / will not go above 410.

I started with a cheap SS thermometer from Wal Mart when that did not give me any comfort, I now use my electronic meat smoker BBQ thermometer.

[mehavey]

Look familiar?
https://i.postimg.cc/nhkKJR5H/PC-Oven-Hamilton-Beach.jpg

(Note the SAECO #221 (#2) Tape Tag from my AR casting)

It did slide to mid 500's at mid tray before settling down,
and did have to be set at ~"360" to stay at 390-415....
... before the PID.

Now it's very well behaved. [smilie=p:

[gnappi]

Look familiar?
(Note the SAECO #221 (#2) Tape Tag from my AR casting)

It did slide to mid 500's at mid tray before settling down,
and did have to be set at ~"360" to stay at 390-415....
... before the PID.

Now it's very well behaved. [smilie=p:

That's it. Mine was spot on 400 set to ~425 after 20 minutes or so. Have you used two trays at the same time with it? Mine works fine but as a precaution I set my timer on my phone to 25 minutes after the powder starts to melt.