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View Full Version : Mihec's 45 200 SWC mold--My take



lathesmith
06-07-2009, 05:45 PM
Hello all,
Like many of my fellow casters here, I love Lee molds and the 6-cavity design. Alas, we Lee GB-lovers have fallen on hard times, with wait times now extending a year and more. I watched with interest as a fellow caster and shooter, Mihec, introduced a 45 200 grain SWC six-banger mold along the Lee pattern. I meant to get in on the original buy, but missed it. Luckily, I was able to get one of these from a fellow shooter here, and I really wanted to try one of these out. Pardon me, but I AM from the show-me state, after all!
Anyway, to make a long story short, for those of you who don't want to read all the particulars, I am VERY pleased with this mold. I began with a light cleaning with carb cleaner and compressed air , and then a light coat of graphite mold release, along with some 50/50 alox for the pivot contact points. I mounted it on a set of Lee six-cavity handles, fired up my Lee drip-o-matic 20lb pot, and was anxious to see what I could do with this mold. Now, when it comes to alloy, I'm not really very particular; I just use mostly scrap lead, wheel weights, and then add a bit of solder for tin; I don't pay much attention to exact alloys or mixes. I pre-heated this mold with my hot plate and after 20 minutes or so I started casting.
What I found was, this mold more or less was like casting with any other Lee six-banger mold, and I was making good-looking bullets right from the start. Like all my multi-cavity molds, it likes to run HOT. In fact, with this mold I couldn't seem to get it too hot; I never could get frosted bullets,even with the heat turned up nearly all the way. I think this may be because the material that Mihec uses for this mold is somewhat denser than the 6061 aluminum that Lee uses, and it seems to really handle the heat well. I need to do more casting to confirm this effect, but so far that is my impression.
I measured some cast slugs, and they were right at .454, +.0008, -0005 or so. I was really amazed at this, the slugs varied less than .001 between cavities, and were also less than .001 out-of-round. These are specs I would expect for bullets after sizing--a $95 mold that casts them this good before sizing is a very impressive piece of hardware indeed!
I did size a few, to see what I came up with, and after running them through one of those lathesmith 452 Star dies (that guy sure makes some NICE Star dies, heh heh) the bullets came in right around .4515; I'll be interested to check them after they have set for a day or two.
Now, I know that some guys would love for me to bash Lee at this point, but I'm not going to do it. Lee can make a great 6-cavity mold at an reasonable price, that represents an outstanding value, and any time I can get one of these within a reasonable time frame, I'll do it. Now though, if this mold is a portent of things to come, there is now another mold maker whose product is just as good a value as the Lee's, if not better. And, within a reasonable time frame, AND with a schedule that makes sense! What's not to love about that?
I know some of you guys will also want to know how these shoot, and so do I. But at this point, the mold has done the job it was supposed to, and making them shoot will be MY job. BTW, I didn't bother weighing these, as weight variance can be as much a function of casting technique as cavity-to-cavity size variance. And with cavity-to-cavity size variance so small, I would expect only miniscule weight difference based on that factor alone.
As for me, I want more of these molds; the material that Mihec is using seems to possess outstanding casting qualities, and his work is top-notch. Thanks a bunch Mihec, with molds like this you WILL be getting more of my business!
Sincerely,
lathesmith

Springfield
06-07-2009, 07:46 PM
Did you noitice any difference in the performance of the sprue plate, being that LEE's is aluminum and Mihec's is steel? I just received a steel plate from Mihec(thanks, Miha!) to retrofit a LEE mould I had to see if it worked any better with a small 38 mould I had.

475/480
06-07-2009, 08:05 PM
Yes ,well said.


Sean

1911sw45
06-07-2009, 09:31 PM
Lathesmith, I am glad you like the Mihec mold you got off me. You done a great write up about it. Yes, Miha does a great work on his molds, it shows he's a shooter and he cares about what kind of product he puts out. I hated to part with his works, but I had for right now. Miha keep up the great work. I hope I will be doing business with you again in the future.

1911sw45
Adam

New Lead Man
06-08-2009, 08:57 AM
Excellent review of a quality mold.

However, I have frosted boolits with mine. Now this is from my very limited casting experience. I got the mold up to temperature by pouring into the mold by holding the sprue plate open and letting the lead heat the mold up. After about ten drops, I could cut the sprue without a lot of effort.

The first few drops had wrinkles in them, which cleared up pretty quick. Then the longer I cast; the more frosted the boolits. I turned down the setting on the pot from 8, then 7. I added more ingots to get the lead cooled down. Then I got called away from the task; the test run was over. I did not weigh or check dimensions of the boolits, this was more of a run to get the feel of casting.

The lead used is smelted from our indoor shooting range backstop, so the exact composition is not known. This may be the reason for the frosting, I do not know.

Take this information for what it is worth and the mold operators extreme lack of experience.

I will be buying more molds from Miha.

lathesmith
06-08-2009, 11:02 AM
Springfield, I couldn't really tell any operational difference between the sprue plates, both seem to work well for me. I'm not really sure what material Lee uses for theirs, but as you say it is non-ferrous.
Adam, thanks again for your quick shipping, and I hope that all goes well for you there.

NLM, it sounds like your experience shows you can get the mold plenty hot. I was just basically confirming that I can run this mold fast and hot without having to pause and cool it as much. Each mold and mold material operates a little different it seems, and requires a slighly different approach.
lathesmith

Springfield
06-08-2009, 11:47 AM
I have a mould that casts 105 grain 38's, and I have found to get the base to fillout I had to run really hot, so hot that I was getting base damage. My theory was that the steel sprue plate would retain heat better than the aluminum and so I could run the mould a bit cooler and still get good fillout. I have cast with it twice so far with the new plate and it seems to be working out better.

dragonrider
06-08-2009, 11:49 AM
I knew I should have bought that one,.............. well maybe it will come around again.

MiHec
06-09-2009, 08:16 AM
Thanks for review

:drinks:

crf250x
06-09-2009, 07:54 PM
The batch of bullets that I cast came out really nice. Refer to my post in the original order thread. I used the bull shop sprue plate lube and the mold still looks practically unused after casting about a thousand bullets. I did notice that the mold liked to be run hot. I was able to get some hot enough to frost though, if I ran just the one mold. I ran two molds, the Lee and this one and the temperature was perfect for perfect bullets. They came out really shiny and with the sharpest shoulders and bases I've ever seen.

When I tested them at the range, I got some very good accuracy from my wad gun at fifty. I can keep them all in the 10 ring and mostly in the x off the bench. I did notice that it had a sharper recoil though. My 3.9 be load can be lowered I guess to about 3.7.
Those sharp shoulders sure cut a nice clean hole in the target, just like a 38 wadcutter, only bigger.

Catshooter
06-09-2009, 09:38 PM
The facisnating thing about his moulds is that each half of the cavity is machined seperatly. Seperatly! Shows the precision of both the CNC and the skill of the operator.


Cat

Bob Maerdian
07-23-2009, 12:37 PM
Does M-P make any rifle bullet molds??
Bob

ddeaton
07-23-2009, 12:49 PM
Does M-P make any rifle bullet molds??
Bob


Bob, he is just getting started. He will make anything there is an interest for. If you have something specific, ask in the group buy threads. Swede is new also, and seems to be doing some rifle stuff now. there is a .311 buy open as we speak.

Cap'n Morgan
07-24-2009, 05:35 AM
The facisnating thing about his moulds is that each half of the cavity is machined seperatly. Seperatly! Shows the precision of both the CNC and the skill of the operator.

:hijack:
That is indeed amazing. To maintain the degree of roundness the members in here reports, it means the mold faces and the cavities must be milled during the same setup. I'm curious as to why Miha settled on this approach instead of just interpolating the cavities in a closed pair of blocks. Better chip evacuation perhaps..? Miha?

happy7
08-17-2009, 10:50 AM
Just a note of info. The #190 top punch works quite well for this boolit if you want an extertal top punch.

MtGun44
08-17-2009, 09:58 PM
He cuts the cavities with a cherry, so closed blocks would be impossible if there
are lube grooves.

On cool thing about CNCing one half at a time, you could cut a smaller than normal diam
cherry and then run it normally to get small cavities, or run it in tiny circles to get slightly
larger versions of the same boolit from the same cherry. OR - if the cherry wears or is sharpened
and is undersized - run it in a tiny circle to get the old std diameter hole (actually half a hole).

One cherry, a range of mold diameters is available. . . . Cool.

Bill

hammerhead357
08-18-2009, 12:47 AM
mtg44 am I missing something here? I thought that several makers used cherry's and were able to do closed block cutting. Maybe I am not used to the term.
I was talking to Wayne Gibbs several years ago and he told me that they had a woman that was ruff cutting the moulds and then he would finnish cutting them by hand. I was under the impression that they were cut via closed mould.
I am sorry if I don't understand the terminology since I am not a machinist. Please feel free to correct my understanding I will not take offense....Wes

Dale53
08-18-2009, 01:30 AM
hammerhead357;
Take a look at MiHec's web site:

http://www.mp-molds.com/index.php?pr=R_and_D

Watching the video (give it time to load) showing CNC operation is a revelation.

Dale53

Cap'n Morgan
08-18-2009, 10:26 AM
He cuts the cavities with a cherry, so closed blocks would be impossible if there
are lube grooves.

Well, that's the beauty of CNC; You can machine the mold cavities with a cherry smaller than the finished cavity. You can also machine the cavities with the mold halves clamped together. All it takes is a cherry with an outside diameter smaller than the diameter between the ribs in the mold (the ribs, of course, form the grooves in the boolit)

These two cherries are both smaller than the molds they were intent for, but will also cut all the larger sizes you can think of. The on on the left is a two-flute helical cherry for a .375 mold and the other is a single lip, straight flute for a .266 mold for my 6.5 x 55. It is only .236 in diameter, but stiff enough to cut a 1.10 deep cavity in a brass mold. Both are made from micrograin carbide.

http://img35.imageshack.us/img35/3435/cherriesf.jpg (http://img35.imageshack.us/i/cherriesf.jpg/)

To reduce the strain on the cherry the cavity are drilled almost to final depth with a drill as large as possible. Then the cavity is drilled to final depth using the cherry. The cherry then describes a number of circular motions (interpolating) milling the cavity to final size. This is normally done in increasingly larger circles, where the cherry is pulled out of the cavity between the cuts to allow for the chips to be blown out (a mill with coolant through the tool is high on my wishlist) [smilie=1: Once the program is finished you can measure the diameter of the cavity and if it's too small you just adjust the program and run it again.

MtGun44
08-18-2009, 01:24 PM
Cap'n Morgan,

I had not considered planning to make the cherry undersized enough to then run it
in closed blocks. Should work fine as long as the cherry isn't so undersized as to be
too flexible, and even then, some final passes to take the spring out would do it.

I think that Mihec's cherry's are conventional, from looking, but you can't really tell
much. I think if he was using undersized cherries and then running them in a circle rather
than just spinning them like a drill, he would not cut the blocks seperately.

hammerhead357 - if you are meaning what Cap'n Morgan is saying - running an undersized
cherry in a circular path to cut the diameter you want, you are correct. However, conventional
'old time' mold cutting had the cherry spinning in a fixed position and the two halves of the
mold block were moved very precisely together into the cherry with a precision vise so that
eventually they met at the exact center. Of course, any slop in the vise or inaccuracy in setting
the vise up centered on the cherry would get the cavity a tiny bit off center and the mold
would not easily drop boolits.

Mihec - please jump in and let us know what you are really doing !

Bill

hammerhead357
08-18-2009, 02:16 PM
mtgun44 after I thought about what I wrote the lite came on for me. I know how the conventional method was or is done. I need to think before writting sometimes!!!!

Am I correct in that the closed mould technique would be used if the maker was using a boring bar to cut the cavity?

I hadn't even thought of the method that Capt Morgan described until he did so. I guess you can tell that I am not a machinist.....Wes

machinisttx
08-20-2009, 06:58 PM
mtgun44 after I thought about what I wrote the lite came on for me. I know how the conventional method was or is done. I need to think before writting sometimes!!!!

Am I correct in that the closed mould technique would be used if the maker was using a boring bar to cut the cavity?

I hadn't even thought of the method that Capt Morgan described until he did so. I guess you can tell that I am not a machinist.....Wes

Examples of the cutters used are on page 1. A boring bar could be used, but it would require several of them ground in different forms to get the job done. Multiple tools would mean the chances of inaccuracies are increased since each tool has to be set individually, and then the variances compensated for by machine offsets. Also, a boring bar small enough to cut most mold cavities would have a ton of push off and would have to run the same path multiple times to achieve the desired dimensions of the feature being cut.

mroliver77
08-21-2009, 08:37 PM
mtgun44 ,
He uses an undersize cherry Here is link Miha posted to show the process.
http://www.youtube.com/watch?v=RjAmbLqeNt0
Jay