359-125HP (9mm), 4 cav. or 2 cav. Brass - MP Molds (MiHec) Group buy - re run

[mgread]

Time to head home and start my cleaning the mold.

T-2.5 hours

[chrisstophere]

My mold showed up today too! Yay! Thing is, this my first mold with pins and I'm not sure how to put this all together. Hopefully YouTube has something.

[mgread]

Here my put together

[mgread]

Here the first run with the wad cutter in it. What I'm I doing wrong?

[chrisstophere]

Here the first run with the wad cutter in it. What I'm I doing wrong?

That looks like either a cold mold or not hot enough melt based on my aluminum experience. Just a thought, raise you lead up by 50 or so degrees and leave them sit in the mold for longer than needed to get it up to temp safely (yeah, I'm worried about warping the mold)

[mgread]

I'm at 725 on my PID and 700 on the Thermometer.

[chrisstophere]

When that's happened to me using the Lees, it was suggested to get my melt up to about 800, pour and cut the sprue when it solidifies but leave the bullets in the mold for a bit longer, then dump them into the sprue pile. Repeat that process 4 to 5 times, then lower your melt and start the casting session without checking out the dumps. Again, I've only used that method on the lee molds with success.

[mgread]

Start getting good one now I have a other problem





I running at 800deg on my PID +/- 9deg

Any help

[chrisstophere]

Is your sprue plate too tight? I've read that it should almost be able to swing open on its own weight.

[xacex]

Mine was like that too and no matter how I adjusted it I could not get good bases. Of course my mold was from a previous run several years ago, but same problem none the less. I ended up taking out the roll pin stop, and threading the hole for a stop screw like the NOE, Lee, or Accurate molds I have. The sprue plate goes under the head of the screw, and keep it perfectly flat to the mold without to much tension when adjusted properly. I have systematically done this to several of my Mihec mold because I prefer that set up over a spring washer to keep the sprue plate flat.

[AZBrian]

I have this mold and over 20 other brass MP molds. Based on what I see:

Your sprue plate is too loose. The sprue plate is flat. If tightened down snugly, the cavities on both ends should be flat/level with the top of the mold once the sprue is cut. The only way for you to be getting lead between the sprue plate and the top of the mold is if the sprue plate is loose or if it is warped. Add some of the included lube to the pivot screw/washer.

The smearing of the lead on top of the mold/bottom of the sprue plate is because the lead is still too hot when opening the sprue plate. Either you are opening it right away, the sprue plate is too hot (happens after a while of casting and then may need to let it sit for a couple minutes or adjust your melt temp down), or the melt temp is very hot and you are not waiting long enough for the lead to solidify.

Based on the wrinkled look of your bullets, your mold is not hot enough. Are you preheating your mold? I put mine on a hot plate for a good 15 minutes @ 400F before I start casting. Even then, I need around 10 rounds of filling the mold before they come out perfect. If you are starting with a cold mold, it will take you a while to get it up to temp. Brass takes much longer than an aluminum mold to get running right for me.

I'd snug your sprue plate down (won't swing freely when tilted), preheat your mold, set your melt temp to 750 degrees, fill your mold, letting some excess lead pool on top of the sprue plate, cool 15 - 30 seconds at least, and discard - repeat fill/wait/drop until they start to drop perfectly. I experience what you see with wrinkled bullets every time when warming up the mold to operating temp. Then when running, I will find lead smearing across the top of the mold when it gets too hot - maybe at the 20+ min mark. Slow down your cast rate or lower your melt temp slightly (I find that the MP molds like the melt to run around 750 for me - varies with bullet size). I'll wipe the lead off the top of the brass mold with a cotton rag and let the mold sit for a min or two to cool slightly, if this happens. When I have wanted to cast as fast as possible, I keep a damp rag and press against the top of the sprue plate (mold empty) every several fills. I am sure folks would not recommend this, fearful of warp. Hasn't happened to me but do at your own risk.

Good luck on figuring this out. When I made the transition to brass molds, it took me a while to get the hang of it. You can get perfect bullets with experience. Spend an hour of continuous casting and watch how it changes over time. The first couple batches may be good for learning only...

AZBrian


Oh, one more note - don't get any lube inside of the mold! If you do, you will also get wrinkling. A drop on each HP pin where it goes through brass body, a drop on the sprue plate screw, and a drop on the handle-to-mold pins/screws. If you get any inside the mold, just spary with some brake/carb cleaner to clean out.

[chrisstophere]

Mine was like that too and no matter how I adjusted it I could not get good bases. Of course my mold was from a previous run several years ago, but same problem none the less. I ended up taking out the roll pin stop, and threading the hole for a stop screw like the NOE, Lee, or Accurate molds I have. The sprue plate goes under the head of the screw, and keep it perfectly flat to the mold without to much tension when adjusted properly. I have systematically done this to several of my Mihec mold because I prefer that set up over a spring washer to keep the sprue plate flat.

That's not a bad idea at all. I'm going to file that for later. Luckily I'm not having a single issue except not enough C clips. Going to run to Lowes and see if they have any of them.

[2wheelDuke]

That's not a bad idea at all. I'm going to file that for later. Luckily I'm not having a single issue except not enough C clips. Going to run to Lowes and see if they have any of them.

I only use one on each cavity for my Mihec molds. All the C-clip really does is act as a stop. I left the rest in the bags. Then it's half the work when I change pins.

[MiHec]

I only use one on each cavity for my Mihec molds. All the C-clip really does is act as a stop. I left the rest in the bags. Then it's half the work when I change pins.

One e-clip is enough per set Rest are spares...