New mold... MP 432-640 Hollow Point, 2 Cavity Gas Check

[44Blam]

Wow. This thing is pretty impressive. But I must say it has a lot of parts!

266414

[StuBach]

They are amazing molds.

If you haven’t had a brass mold before. Make sure you disassemble and clean fully to remove any trace oils left over. Than heat cycle the brass blocks a couple times on a hot plate or in a toaster over to start building the patina. I usually run mine 4-6 times in the toaster oven up to full temp than let it cool back to room. Will make your first casting session much more enjoyable.

[Mal Paso]

Heat cycle with the mold open to get oxygen to the cavities.

I assemble the mold with the pins on the left as you hold it.

After I cut the sprues I turn the mold over, open it, gently push the pins out and the bullets fall off the pins.

[Shuz]

Once you assemble the sliding pins to the hollow point pins, back the sliding pins back out about 1/4 turn. This makes for much easier overall operation than with the sliding pins tight up against the hp pins.
Also, I have found that only 1 sliding pin on each set of pins needs an "e" clip.
On my 4cavity mould of the exact same design, I have found that the weight of the penta pin boolits is the same as the regular hollow point pin boolits. Congratulations on owning a fine design and a superbly manufactured mould. Good luck with it!

[DHDeal]

This will seem obvious, but it escaped me the first time I cast with an MP brass HP mold. Make sure if you're ladle casting to put your sliding pins on the off side (which ever side that is for you). If you don't and the molten alloy pours over the pins, it'll be fun, but not really.

All good advice given so far and a few above I've read their posts of the trials and tribulations with these molds. I believe I'm up to 9 of them and consider them easy to use and make perfect bullets with. There are some tricks, at least for me, such as heat cycling and using my ultra sonic cleaner. I did just throw one particular mold under the bus and assemble it and go to casting and it did OK.

The only downside to your mold is it's a 2 cavity. I've got one 2 cavity and ended up ordering an identical style 4 cavity in short order.

[44Blam]

Great advice!

I did cycle it in the toaster oven a couple times last night. I also generally scrub all my new molds with soap and water to break up and clean off the machine oil.

I noticed that if the sliding pins in the points are very tight it makes it harder to move in and out. So, I played with it a little and found that if I tightened the pins and then backed it out it did make the pins slide a bit easier.

I did put the pins on the right side because I'll break the sprue plate open with my right hand and then open and then push the sliding pins out with the right hand... Will have to see if that works or if it needs to go to the other side.

I had one question I was pondering about the mold lube. I'll lube the alignment pins and the top of the mold/sprue plate like I do with my other molds but I think I might also put a bit of lube on the sliding pins. That shouldn't get into the cavity and might make the pins go in and out a bit better... Did you all do this?

[DHDeal]

I keep strong bamboo qtips coated with lube on my casting table to wipe onto the sprue plate, alignment pins, and HP pins as I cast. I probably lube every 20-25 fills or if necessary.

As far as which side and end to set your mold in the handles, you'll figure it out pretty quick. I always cut my sprue with my gloved hand when up to temp and keep the pins on the left side (when attached to the handles), but that's me. I ladle cast only.

If you've read the many threads about the brass molds you've read where some mention "tinning". A few state they've never seen it and others have. I have and still see it occasionally. Maybe it's something I'm doing, maybe it's too much tin, maybe it's because brass molds hate South Carolina. Regardless, I watch my molds faces and if I notice any alloy starting to stick (tinning) I keep a piece of burlap that I'll rub on that area when the mold is hot and keep on casting. I'll also look at the molds after they cool under my large lighted magnifying glass and use a carpenters pencil to get any minor gunk off afterwards. A brass mold is a marvel to use but they are different than a steel or aluminum. When I'm casting with an Accurate Mold I think they're the easiest mold to use, then when I'm using a seasoned MP brass, I think the same.

The HP sliding pins will loosen as you cast, so I also keep an Allen wrench handy on my table and will tighten or loosen during a session. Yes, using a MP Mold is more involved than say using an aluminum Accurate Mold, but when you're used to them and in the rhythm it's just what you do to keep those wonderful HP bullets falling into the bullet box. Makes me want to get the pot up to temp an cast a few hundred but I don't cast in the summer here.