Need help with a MP HP brass mould

[BrassMagnet]

Yesterday, I fired up a 380-93-HP mould. It took a while to get it working and then it worked for a while and then went to crap.

So I assembled the HP pins by hand and started off. I finally smoked the pins to get them to release Boolits. Smoking and more heat finally got it to release Boolits reasonably well. I cast a few sets of four and then it went to crap.
I was afraid I had managed to warp it in a mere half hour or so. Then I noticed the rods holding the HP pins in place had come loose! Pretty hard to tighten them finger tight when hot!

Now what do I do? Is there a high temp locktite I should have used?

Note: This sure is a cool boolit! I have found I can substitute this boolit in to my loader when I have been loading the 95 grain 358242 without adjusting the dies or powder measure! WooHoo!!! I just need to learn how to peacefully co-exist with a HP mould.

[RickinTN]

On the pins use a #2 pencil or carpenter's pencil and cover them well with graphite. This will help the pins release. I watched a video in which it stated to tighten the rods tight, then loosen 1/8th turn. This will allow the rods to float in the mold and not bind. The Mihec hollow point molds are a little different than any I've used before but once you learn their personalities they run well.
Good luck,
Rick

[Minerat]

I haven't had issues with the pins coming loose but I use the allen wrench to tighten them down. I mostly have sticking when the pins are rough. To fix that I put them in a drill and polish with fine wet/dry sand paper. Then use a lead pencil to color the tips which helps release too.I also lite tap the pins when opening the mould to push them out that helps release the bullets. If I get the mould too hot it can break out the side of the HP.

[BK7saum]

I also leave the pins about 1/2 turn loose. On some molds if the retainer slide pins are tight, the pins don't freely slide. Polished pins or graphite help with bullet release.

[BrassMagnet]

Thank you for all of the great help!

I did not know the rods could be tightened with the Allen wrench. So I wrenched and lubed with graphite. Much nicer now!

[StuBach]

Enjoy, that is a fantastic little bullet in 380 I’ve found.

[Wheelguns 1961]

Thank you for all of the great help!

I did not know the rods could be tightened with the Allen wrench. So I wrenched and lubed with graphite. Much nicer now!

Make sure you back them off 1/4 turn from tight, or they will expand when heated and may not slide freely. They have some very good videos on mp-molds.com. All kinds of good tricks!

[Shuz]

Thank you for all of the great help!

I did not know the rods could be tightened with the Allen wrench. So I wrenched and lubed with graphite. Much nicer now!

Not all the MP Mold hollow point pin sliding rods can be screwed in and out with the little allen wrench. Some of Miha's earliest molds just used pins with a small flat on the ends. Being able to use the Allen wrench is a great improvement. I too have found that the pins slide easier if backed out about 1/4 turn. I have also found that a guy only needs to use 1 E clip per pin. That keeps many of them from being launched into orbit in my shop!

[Wheelguns 1961]

I used to not worry about having 2 clips per pin until one fell off and I had no clips on one. I opened the mold and the whole assembly fell out

[DHDeal]

Like the others stated, keep them loose. I don't measure 1/8 or 1/4 turn (and neither do the others) but I'll run them in tight and back them off making sure the c clips don't bind. I have a tiny allen wrench with a handle made by or for RCBS that fits the 4mm set screw. I keep it and a 6mm allen wrench on my casting table to do a tune up occasionally when casting. If you get into the groove and bullets are raining, if you're not paying attention the pins will loosen and the mold will start acting up. Do a quick lube and tighten tune up and cast on.....

[StuBach]

Recently Harbor Freight was running a special on their T-Handle Allen wrench set for $12 per set when you had the coupon. I ended up buying a set of those specifically to pull the appropriate sizes out for my casting bench needs. Helps keep hands clear of heat when having to tune up pins or sprue plate screws

[Wheelguns 1961]

I have also had the pins that hold on the handles come loose. I use a noe mold guide, and they drag on it, and must be tightened.

[Handloader109]

I've a 2 cav 358429 that works great when it is HOT. And screws are allen wrench tight. Not overly, but tight enough not to loosen when cycled. I played with it cold for a bit to make sure the it did slide easy.

[curioushooter]

Get everything clean. Then carefully assemble and use pencil graphite to lube the pins.

Be careful about temp. Brass molds like to be run at 750 at least. They have a narrow window where they work well and if the pins get cold it's a pain. You need to cast fast and have everything just so. If you can cast good HPs solids are trivial.

When you tighten the pins into the studs that hold them you should not bottom them out and back them off 1/16ths of a turn. No loctite should ever be necessary anywhere on a mold if you are using it right.

Use just tiny, tiny amounts of the provided lubricant. It is definitely better to pour some lead into the cavities then wipe the top of the blocks very sparingly with the lube. If any lube migrates to the cavities or on the parts of the pin that contact alloy it's a disaster. A toothpick with a dab on it's tip is excellent for anointing the sliding cramer pins from the outside of the mold after being assembled. The lube will migrate to where it needs to be. One tiny dab is enough for each pin.

In general brass molds do better the more you use them. They develop a patina that improves performance over time. They pretty much stink the first two or three times you cast with them.

[mattw]

Like others have said... polish the pins, maybe graphite them the first few runs. But, the key is heat. The pins need to be hot and they heat up slower than the moulds. I use a little pencil torch to add heat to the pins until they come up to temperature. They do not heat up well on the hot plate and NOE are even worse to heat on a hot plate as there us stuff below the bottom of the mould blocks. I run all my pin moulds between 730 and 750, once they get frosty slow down and the pins will stay hot.