Am I being too picky?

First of all: I like MP molds. I have 7 & I'm on a group buy for 2 more.

I have a MP 359 Hammer 8 cav. alum. mold that was acquired through a GB. I cast outside & the extreme heat in S. GA prevented me trying it until the 1st cool morning lately. It didn't take long for it to start dropping some keepers & I was able to cast over 800 before the heat shut me down. The batch looked good, but when I finally got around to sizing/lubing I recognized a problem. They all had a pronounced part line & were slightly out of alignment.

I size my Rugers to .359 & my S&Ws to .357. I tried sizing .359 1st & recognized the problem. I figured that the .357 dia. would size out the minor misalignment, but it failed to do so. Also for some unexplainable reason they measure .35650 when sized in the Star .357 die. Everything else comes out of that die @ .357 (?). (all measurements made with a micrometer.....not a caliper).

I stripped the die & could feel a very slight front to rear movement between the 2 halves (very slight.....barely perceptible). There was no light visible between the halves. On a flat surface I tapped each pin & afterwards there is not movement (also no light). The next day I cast a few more & when they were sized I could see some improvement, but not perfect. I stripped the mold blocks again & gave the pins a good tap while positioned on a flat surface.

Today I was able to cast about 75-80 @ a higher heat that produced frosty boolits & about 75-80 more @ a lower temp (shiney boolits). I don't see any improvement & it looks like I've reached maximum improvement. Also note that the mold halves were fully closed resting on a 8" 1"X4" for alignment & the mold handles were gripped @ the very end: past the end of the sprue handle (sprue handle not touched when casting).

I've made some photos so you can understand what I'm up against.

Photos:
#1 & 2: View of the stripped blocks (top side). Initial impression is that they're OK, but the more I look @ them I think I see minor misalignment between 3 or 4 cavities ( maybe an allusion).

#3: average appearance of boolit sized to .357

#4: One of the worst

#5 & #6: close-up view of un-sized boolits showing typical part line.

I'm open to suggestions as what I can do to cure the problem. Also welcome any explanation about the .35650 size from a .357 die when sizing a boolit that starts off @ .359+.

Am I over thinking this or am I being too picky? I have this same design in a 162 gr. Arsenal mold & in a 43-210 Accurate mold & they don't have these problems. In fact I have 2 MP molds of this same boolit both 2 cav. brass: 1 in PB & 1 in GC & they don't have these problems.

Any input is appreciated.
Henry

Take a picture of alignment pins - both halves

Bought an aluminum 358009 on the forum that later learned had alignment problems due to wiggle.
Ruins the boolits so I feel your pain.
No, you're not too picky!

Oh, and I contacted the manufacturer on what I could do to correct the wiggle, such as extend the pins a little. The answer I got back was that it would make the pins become loose. That's a problem apparently with aluminum unlike with iron. So I'm wooed, boohooed and what goes in between because there's no way I'm gonna sell bad blocks to somebody else.

would there be some way to bolt something to the front of the half that's back more so it holds pressure back on the other side? probably something that's curved and springy so it engages as closing. I guess youd have to confirm it can make good bullets if its held in the right slack take up. but if it was mine and Its not working right and I don't wanna sell it cause its defective id break out some tools and rig it up to work somehow if possible.

Quote:

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Originally Posted by MiHec

Take a picture of alignment pins - both halves

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The forward female pin (@ the sprue plate pivot end) is distorted slightly. I know now that this distortion is a result of the 1st casting session. I noticed that when I'd close the mold the forward male pin would sometimes strike the edge of the female pin because the halves were not going together squarely. After I noticed this I would need to maneuver the sprue plate side into position to prevent this from happening. After the 1st. session I experimented with different ways to get the 2 halves to align. I ended up draw filing the edge of the handles slightly where the mold is attached & also tightened the pivot bolt to remove all side-to-side movement, but still allowing easy opening & closing. I did this with the MP handles & even tried a Lee handle to see if they would align better. I ended up with the adjusted version of the MP handles.

Can the female pin be purchased separately? It looks like something relatively easy to do. Or, do I need to return the blocks to you?

Many thanks for your LD diagnosis.

Henry

Quote:

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Originally Posted by bmortell

would there be some way to bolt something to the front of the half that's back more so it holds pressure back on the other side? probably something that's curved and springy so it engages as closing. I guess youd have to confirm it can make good bullets if its held in the right slack take up. but if it was mine and Its not working right and I don't wanna sell it cause its defective id break out some tools and rig it up to work somehow if possible.

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See my reply to MiHec. I think he has the problem solved.

I had a similar problem with a new noe mold, except my alignment was off top to bottom. Apparently the pins didn’t seat when preheated. I tapped the male pin slightly out and problem solved. I make sure I lube my pins every time, and I also make sure I don’t overheat the mold.

I owe Mihec an apology & I hope that my posting of this thread does not reflect negatively on MP Molds. In hindsight I wish that I'd made a better inspection of everything & found the distorted female pin. The distortion of the pin is my fault. I should have been more alert to catch the problem of the male pin striking the edge of the female pin.

I accept full responsibility for the resulting damage.

Henry

Quote:

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Originally Posted by oldhenry

I owe Mihec an apology & I hope that my posting of this thread does not reflect negatively on MP Molds. In hindsight I wish that I'd made a better inspection of everything & found the distorted female pin. The distortion of the pin is my fault. I should have been more alert to catch the problem of the male pin striking the edge of the female pin.

I accept full responsibility for the resulting damage.

Henry

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You came looking for advice, not bashing! The manufacturer responded and help is on the way.
This shows he stands behind his products.
I how all turned out well!

Quote:

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Originally Posted by oldhenry

The forward female pin (@ the sprue plate pivot end) is distorted slightly. I know now that this distortion is a result of the 1st casting session. I noticed that when I'd close the mold the forward male pin would sometimes strike the edge of the female pin because the halves were not going together squarely. After I noticed this I would need to maneuver the sprue plate side into position to prevent this from happening. After the 1st. session I experimented with different ways to get the 2 halves to align. I ended up draw filing the edge of the handles slightly where the mold is attached & also tightened the pivot bolt to remove all side-to-side movement, but still allowing easy opening & closing. I did this with the MP handles & even tried a Lee handle to see if they would align better. I ended up with the adjusted version of the MP handles.

Can the female pin be purchased separately? It looks like something relatively easy to do. Or, do I need to return the blocks to you?

Many thanks for your LD diagnosis.

Henry

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Take a look at my modification to the handles that take out the play and prevents divots due to pin alignment: http://castboolits.gunloads.com/show...ns-handle-slop

Quote:

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Originally Posted by dahermit

Take a look at my modification to the handles that take out the play and prevents divots due to pin alignment: http://castboolits.gunloads.com/show...ns-handle-slop

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I can readily see the advantage of your modification now. However, before this particular pairing of this mold & handle I would not have understand the problem that you solved. I am accustomed to bolting mold to handle after prepping the mold & begin casting. In my case the left side (w/male alignment pins) kept lagging behind rather than pivoting into place. Looking back, I should have addressed that problem then rather than continue casting: but with a new mold you know how it is...…..you want to see the boolits.

Tightening the handle hinge bolt helped, but your alteration may be needed for this particular mold/handle pairing.

Thanks for that reference.

Henry

Pins not replaced yet: long story.

Since the female pin was only slightly damaged on one edge, I set out to find something suitable to lap that pin defect away. As it turns out a 5/16" drill end has a bevel that makes it suitable.

1st. lapping followed by some taps on the pins produced some results. The 2nd. attempt followed by taps on the pins produce more results. I tested the progress casting about 150 boolits. This casting produced some inconsistent results. I didn't want to cast more without sizing to test results (I've already returned 800+ to the pot).

Images:
1. Female pin after lapping & after some very slight clean-up work with a jeweler's file
2. End of the 5/16" drill
3. End of drill positioned on female pin.
4. Results: the one on the left is better than the one on the right
5. Side by side comparison: 8 cav. solid on left & 2 cav. brass HPGC on right

I'm on 3 active GBs & 2 of which should end soon. I plan to ask the people @ MP to include a set of pins when they ship the 1st. GB that matures.

I'm beginning to think that the primary alignment (before contact) is the problem & the Lee type 3rd. handle may be the cause. With this particular mold & handles I need to be very particular in closing: positioning the 2 halves on a flat surface is mandatory.

Henry

I cast about 700 2 days ago & got around to sizing slightly over 50 today. The cast & sized boolits look good: seam line is barely perceptible .

No boring details: I just continued with the process described earlier ( I guess I just got better at it).

Henry

Reason I got away from aluminum molds. I just have bad service out of them personally.

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Originally Posted by TheGrimReaper

Reason I got away from aluminum molds. I just have bad service out of them personally.

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I didn't give up on them altogether: however, on a recently closed GB & another open GB I chose 6 cav. brass rather than the 8 cav. aluminum.