New 40 cal MP mold with Penta pins...sticky

[JonB_in_Glencoe]

first time casting with a Brass MiHec HP mold
a 2 cavity HP with Penta pins.

I did wash the mold in hot water, toothbrush, dishsoap.

First, the sliding pins connecting the penta HP pins are snug in the blocks, are they suppose to be ?

Also the boolits stick to the HP penta pins.

I applied a light coating of the MP mold lube (similar to Bullplate)
to the sprue plate, allignment pins, penta pins, and slide pins for the penta pins.
this was done after preheating the mold

Does it just take a few casting sessions to lossen up ?

thanks for any advise,
Jon

[shootinxd]

I don't tighten the screw on the pins all the way,it seems to bind them in the mold.I try to clean the mold before each use seems to help also.

[cbrick]

As was suggested don't tighten them down. Yes, a few casting sessions and they should be good, also use the sprue plate lube Miha sends with the mold to lube the pins that go through the block.

Bullets sticking on the pins is almost always because of pins too cool, they NEED to be hot. A cool HP pin will hold onto a bullet like it's welded on.

Rick

[captaint]

I have also tried to remove the side pins from the HP pins and polish them with 400 paper and oil. This doesn't reduce the size enough to matter (like less than .0005). I have one MP hollow point mold that needs pins almost TOO hot. Like I nearly have to flame my melt to get and keep the pins hot enough to drop the boolits. Other molds of his drop the boolits right now.... Next up - smoking the pins. That has worked for some of US. We shall see. Either way, the boolits are exceptional. I have had to, sometimes, literally pull the boolits off the pins with pliers. Those very boolits shot the best group I have ever fired at 25 yards, rested. enjoy Mike PS> The group consisted of 40 rounds.

[JonB_in_Glencoe]

I have also tried to remove the side pins from the HP pins and polish them with 400 paper and oil. This doesn't reduce the size enough to matter (like less than .0005).

thanks for the hints everyone...
I will try casting 3 or 4 sessions (cleaning inbetween) before doing the following.

captaint, wouldn't it be easier to polish the brass...meaning the holes that the slide pins slide through then to polish the pins ? or is this NOT smart ? too easy to screw it up maybe ?

I'd probably use a bambo skewer with flitz...or maybe some kind of wooden dowel or chopstick with flitz, if it's not a dumb idea....maybe a shoe string with flitz ?
Jon

[cbrick]

Jon, I wouldn't do that, I think it would very difficult to polish out the holes and keep them round. I polished the pins on one set by only .001' and Miha said better to not do that and insisted on sending me a new set of pins. It did work and the new pins actually fit a bit better after a few casting sessions, now I have two sets of pins for that mold.

Rick

[jmsj]

Jon,
I have a Miha 359-640 mold that was tight when I first got it but after casting 500-600 boolits the mold worked itself in.
Like you, the penta pins do not release great for me. I tried carefully polishing the penta pins and they are still a little sticky. I even tried smoking the pins but it didn't seem to help much either. The saving grace is that the round HP pins release, look, shoot and expand great. I have had good results casting and shooting the round HP's and flat noses. I may go back and try the penta HP pins again later.
Good luck, jmsj

[edler7]

I've found I have to get my Miha mold really hot to get the Penta pins to release. I tried polishing them (helped a little, for a while), rubbing them with a pencil ( didn't help much) and buffing them with a dremel/buffing pad (not much improvement). I was using it yesterday and noticed that if it sat on the hotplate longer - like when I was remelting sprues- the bullets dropped right off for about the next 7-8 pours...they they slowly started sticking again. So I cranked the hot plate up a little higher and would rest the mold on it whenever I didn't have it under the pot and the pins released the bullets a lot better. Some frost on the bullets, but nothing I can't live with. My alloy was at 725 with a PID controller.

When it was hot enough for the pins to work right, the sprues stayed liquid for 8-10 seconds after being poured.

Run it HOT.

[Iron Mike Golf]

Recently received a 452-270 HP mold. There were 2 kinds of guide pins on the penta-set. One was solid with machined flats by the e-clip slot. Have those on the 432-200 HP mold. The other sort is hollow on the e-clip end and has no flats.

ETA: The second kind is real stiff in the mold. The solid guide pins with the flats fall in and out on their own weight.

The pentas are hollow-ground. I suspected that might be setting up a slight pinch at the corners, so I gently stoned the penta sides. Boolits release a lot easier. Alloy temp is 675 and my hotplate it at 3/4. No idea about mold temp. 20 minute pre-heat on the mold. Satin frost and the boolits fall off on their own weight 99% of the time.

[Dale53]

Use mould release for the hollow point pins. I have .38/.357, .44 Special/Magnum, and .45 Colt Mihec Cramer style hollow point moulds. The mould release is applied only to the portion of the pin that makes the hollow point. I treat the mould every time I use it.

They mostly fall off of their own weight when the mould is opened - those that don't fall, fall when the handle hinge is tapped lightly.

Super moulds in every way but the mould release is a very nice addition:

http://www.buffaloarms.com/Detail.aspx?PROD=161428&CAT=3851

Dale53

[JonB_in_Glencoe]

great,
lots of tricks to try on the next casting session.
starting with using the Non-penta HP pins...and a little more heat.
Jon

[JonB_in_Glencoe]

OK all,
casting session #2 with this mold...a Success !!!
thanks for the tips.
first, i put the standard HP pins in.
I loosened the slider pins in the HP pin,
then they slid easily through the mold.
I pre-heated as usual.
I ran the alloy a little hotter than normal...725º to 750º
and I cast as fast as I could.
I cranked out about 400 in about an hour....then this brass mold started getting heavy
the boolits fell off the pins for the most part.
I love this mold...absolutely love it
Jon

[jmsj]

Jon,
That's great to hear.
I only have a few HP molds but the Mihec mold is by far the fastest mold to use.
jmsj