Mold Problem

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  • Last Post 21 March 2013
PETE posted this 22 January 2013

Without trying to find it by doing a search.(I'm lazy).

I got a Lyman 452424 (Keith style) the other day. The problem is it casts .4505. out of range scrap. First one I've had that cast less than .002 oversize.

I've noticed a time or two that someone with a similar problem was told of someone who could open a mold up a coupla thousandths. So the question is... anyone know of someone they've had similar work done by and what you thought of their work.

Pete

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delmarskid1 posted this 23 January 2013

Sometimes a little tin added to the alloy will make the bullets bigger. Just a thought.

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onondaga posted this 23 January 2013

Hi Pete,

Yes, sorry to say, it could be just you and your casting technique/alloy that is sensitive to the mold.

If the mold is steel or iron it will be very time costly to hone out. Aluminum or brass molds I do for myself.

I have posted a good number of times about getting the largest diameter castings from your molds. Have you read any of those posts and tried the methods?

My range scrap hardness tests at BHN 7-9 and is mostly from jacketed pistol bullets so it is Antimonial lead with about 2% antimony and no Tin to speak of.

That Antimonial lead will benefit greatly with the addition of 2% tin for better mold fillout and pot temp will need to be about 620- 650 degrees F. with a low Tin content of only 2%. A thoroughly clean mold prewarmed to 100 degrees less than than alloy temperature is required for the best fill-out. Mold temoerature can best be maintained by casting at a cadence of 3 drops of bullets per minute. Slower, and your mold will cool, making your bullets smaller

This casting stuff and “Swirl” casting that I have outlined in several posts will maximize bullet diameter and the largest puddle you can manage on your sprue cutter plate top when pouring will help also.

All my inexpensive Lee molds cast oversize with these methods. I have enlarged .309” Lee 30 caliber molds to .3125” for bullets to be large enough for a 7.62X39 that likes bullets sized to .312” .

Give the casting method tweaks a try before you modify the mold. I can control 45 caliber bullet size up to .002” plus or minus just by modifying casting methods and alloy...but I've been doing this since 1956 and have worked as a Casting Analyst and instructor for a Gold refinery's Dental Education and Research departments.

Gary

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Wayne S posted this 23 January 2013

PETE wrote: Without trying to find it by doing a search.(I'm lazy).

I got a Lyman 452424 (Keith style) the other day. The problem is it casts .4505. out of range scrap. First one I've had that cast less than .002 oversize.

I've noticed a time or two that someone with a similar problem was told of someone who could open a mold up a couple thousandths. So the question is... anyone know of someone they've had similar work done by and what you thought of their work.

Pete Do a search for “Beagling ” a mold, this process puts strips of hi temp alum foil tape on the inside faces of the molds.  I've used Eric at Eric hollow pointers to open the driving bands up .002 of some RCBS molds. I sent him samples of the alloy I am using and now the bullets drip  just what I want them to.

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j35nut posted this 23 January 2013

http://www.hollowpointmold.com/#repairs

Here you go lazy bones:)

No personal experience, but never heard anything negative either.

-----J

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R Dupraz posted this 23 January 2013

The driving bands of an iron mould can be lapped out with valve grinding compound and brass cone nuts. I have enlarged moulds up to .0015+” with success using this method.

RD

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John Alexander posted this 23 January 2013

What are brass cone nuts. Please explain.

Thanks.

John

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PETE posted this 23 January 2013

j35nut'

Thanks for the web sight address. Just what I was looking for.

RD,

Have tried your idea out but I've found, for me at least, if the mold is out of rd. then it'll end up being out of rd. the same amount or worse.

To the others who commented.... Thanks for your input. But.... I'm kinda familiar with casting since I've been doing it for right at 60 yrs. casting everything from pure Lead rd. balls to Lino and about everything in between. Started casting rd. balls for a muzzle loader when I was 12 using a 10 pd. Lyman pot and ladle. Still use the ladle.

When I said I'd never run into a Lyman mold, or any other for that matter, that cast this small, that's what I meant from experiences with 85 different molds (I counted them last nite to be sure) that I have in my inventory.

The range scrap I use tests out at 11 Bhn + or- a bit. I have about 1000 pds. of it cast into ingots which is mostly .22 bullet Lead. Don't think I'll add 1% Tin just to get a better bullet since fill-out with this metal gives nice sharp edges and no external voids. I weigh all rifle bullets which run plus or minus .2 gr. with the occasional reject.

The other .45 mold I use for .45 ACP competition and using the same “lot” as above cast bullets .0015 over or right at .454.

So the conclusion that I draw from the “problem” mold is that it needs to be opened up a bit.

But... will try some test loads running up to a max. load and see how they work out. If leading doesn't occur and accuracy is up to what I think it should be then I'll forget sending it in to have it opened up. Otherwise.....

Pete

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Pigslayer posted this 23 January 2013

Don't mean to sound pessimistic but I quit using Lyman molds except For the older ones. I have a 452490 GC & it drops right at .452 Using Lyman #2. That's 90-5-5. Started using LEE aluminum almost exclusively & have no more issues. Although I do have a couple of custom AL molds when it was required. Pat

If someone else had of done to me what I did to myself . . . I'd have killed him. Humility is an asset. Heh - heh.

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R Dupraz posted this 23 January 2013

John:

Brass cone nuts are made to connect copper gas/fuel lines and are made in various sizes. They can be found in any good hdw,auto parts or farm store.

Without going into a long winded tribe here, I center the proper size nut, small end, over the mould cavity, not over the sprue plate, and then pour the cavity and nut full of lead. This allows one to then rotate the lapping bullet in the cavity after it has been loaded with compound. There are a few more details to the method that I have worked out but that is basically it.

Pete:

When I first read about this many years ago and then tried it, the results were not good. There weren't any details given. But this feeble mind said, “there is no reason why this should not work". So, with some fiddleing around, I have had good success lapping the moulds to increase the size of the driving bands only and with about .0005"+ concentricity, using valve lapping compound. One as far as .0015"+, which I have used in a K-98 Israelie 7.62 mm for the military matches. Time consuming but well worth the effort I think.

If anyone is interested, I'll go into detail. Also,following are a couple of photos. The cone nuts and a couple of sighter targets shot by the Mauser with the RCBS 30-180-SP during a military match at the Hawkeye RP club a couple of yrs ago.

RD

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R Dupraz posted this 23 January 2013

Sighter targets, 200 & 100 yd. stages, Hawkeye R & P club military match. Low shots on 100 yd target were sighting adjustments. The down side was that these were the sighters and not record. And No, have not been able to do it again. I now use the RCBS 30-165-SIL. The driving bands in this mould were also lapped out and I think the bullet is a little more consistant in the 13” twist.

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PETE posted this 23 January 2013

RD,

As far as I'm concerned go ahead with more details on how you use this technique. With pictures of course. :) I'd like to think I'm not to old to learn something new.

Pete

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pat i. posted this 23 January 2013

You won't go wrong dealing with Eric at Hollowpointmold. He's modified a couple of moulds for me and they're perfect. Not expensive and a good guy to deal with. If you like the mould I'd just send to to him and have him make it right.

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PETE posted this 24 January 2013

Pat,

Appreciate the recommend on hollowpointmold. First I want to see what the mold will do as is. Then I'll see about sending it in or trying RD's idea. Depends on how I feel. At the age where it's a lot easier to throw money at something than to do it myself. ::)

Pete

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John Alexander posted this 24 January 2013

RD

Thanks for the explanation about cone nuts. I thought I had heard all the ways to go about lapping out a mold -- but you never hear everything.

I will give your method a try the next time I have to lap a mold. Lapping is a lot of work but when either the bands or the nose isn't right is is worthwhile. Like Pete I would like to hear more details, at least the things not to do.

I also have a candidate mold whose nose is way too small and lapping takes time so I think I will let this Eric guy have a go at it. Everyone says good things about him.

Pete Nobody followed up on Wayne's suggestion to beagle the mold. This is a quick and easy method that is offensive theoretically because the bullet is no longer round and most shooters assume erroneously that bullets have to be round to shoot well. I'm not saying that round isn't desirable just that an out of round bullet that fits will shoot better than a perfectly round one that doesn't. I have won a fair share of postal matches with a beagled bullet that was well over ,001” out of round. John

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R Dupraz posted this 24 January 2013

John:

Your comments regarding Beagling mirror my thoughts/experience exactly. I used this method for quite a while on the molds that I use for the K-98 7.62mm.

While the rifle would shoot some fine groups with these bullets from a Beagled mould, the consistancy was not there. Plus, keeping some type of shims in the same place on the inside of the blocks got to be a challenge. Believe me, I tried everything and finally gave up. figured that there had to be a better way.

The lapping method has so far proven to work well for me. And it's permanent. One qualification that needs to be present in the mould at the outset, is that the nose of the bullet must reasonably fit the bore because I have been unsuccessful in attempting to enlarge the nose of the bullet consistantly by lapping.

The first problem that I found with this it that it was nearly impossible to evenly embed lapping compound all the way up and around the ogive of a bore rider. Because of this, due to the distribution of the compound while lapping, the nose would be enlarged more on one side of the ogive that the other. I'm talking very very little, but enough to see that it was happening. Didn't like it.

So,deciding to give up on that, the technique that I use just laps the outside of the driving bands only, nothing else and has proven to make the groups more consistant and repeatable for me.

Anyway, just trying to decide whether to post here or attempt a piece for the Fouling Shot.

RD

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pat i. posted this 24 January 2013

R Dupraz wrote: Anyway, just trying to decide whether to post here or attempt a piece for the Fouling Shot. RD

Write it up and send it along with pictures to Glenn for the FS. He's always looking for good articles and maybe this will turn out to be “The R Dupraz Lapping Method” and you'll get rich and famous.

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PETE posted this 24 January 2013

Took the problem mold/bullets to the indoor range (50 ft.) today and ran 6 5 shot groups using Unique with loads running from 6.0 grs. to 8.5 grs. in 5 gr. increments. Thought I'd get some Leading but nothing showed on cleaning. Guess I'll have to do some more work with it before deciding to send it out to get worked on if RD is going to wait to write a FS article.

Indoor range is 50 ft. With a two handed hold and resting the butt on top of my hand and the bench top the two best groups were 1 1/4” and 1 3/8".

Pete

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John Alexander posted this 24 January 2013

RD,

Pat is right. Write it up with pictures and send it to Glenn. I wouldn't buy a new bass boat and put up your future earnings from getting rich as collateral just yet.

About your comment that lapping is permanent and beagling is only temporary. To me temporary is an advantage I have used one of my favorite molds for several rifles by using more, less, or no beagling.

I also have had no trouble keeping the shims in place until I scrape them out. I use kitchen aluminum foil and glue it in with white glue. The glue doesn't want to wet the foil and is a pain in the ass but I just smear it around and press the blocks together then pour some bullets. Never had any trouble with them falling out.

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R Dupraz posted this 25 January 2013

John:

Aw,Nuts, I was already practicing getting a little “snooty".

I think I probably will try an article for FS, not a big deal but someone else may find the process worthwhile. If I can get this one eyed monster figured out, I'll put it on a disc.

White glue? Never would have thought that it would work. I used Aluminum furnace tape and some other adhesives along with it.

RD

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Lefty posted this 25 January 2013

I have beagled a few molds. I am not sure I would care to do it with my favorite match bullet but it is certainly more than adequate for any other purpose. I use the aluminum heat resistant tape. $6 will buy you enough to last a millenium.

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John Alexander posted this 25 January 2013

"White glue? Never would have thought that it would work." RD

I wouldn't have thought it a top candidate either but in was on the bench and it worked so I have kept on using it.

John

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Muskrat Mike posted this 25 January 2013

R Dupraz wrote: John:

Brass cone nuts are made to connect copper gas/fuel lines and are made in various sizes. They can be found in any good hdw,auto parts or farm store.

Without going into a long winded tribe here, I center the proper size nut, small end, over the mould cavity, not over the sprue plate, and then pour the cavity and nut full of lead. This allows one to then rotate the lapping bullet in the cavity after it has been loaded with compound. There are a few more details to the method that I have worked out but that is basically it.

Pete:

When I first read about this many years ago and then tried it, the results were not good. There weren't any details given. But this feeble mind said, “there is no reason why this should not work". So, with some fiddleing around, I have had good success lapping the moulds to increase the size of the driving bands only and with about .0005"+ concentricity, using valve lapping compound. One as far as .0015"+, which I have used in a K-98 Israelie 7.62 mm for the military matches. Time consuming but well worth the effort I think.

If anyone is interested, I'll go into detail. Also,following are a couple of photos. The cone nuts and a couple of sighter targets shot by the Mauser with the RCBS 30-180-SP during a military match at the Hawkeye RP club a couple of yrs ago.

RD

Ask for Flare Nuts at any plumbing supply house and you'll get them!  they come  sized to fit copper tubing OD sizes. ie 1/4"od 3/8"od etc.

Muskrat Mike

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Hoot McGraw posted this 21 March 2013

I Have recently brought a 4 cavity mold from layman to cast 45 acp , it was dropping at .449 to .450 depending on how i held the caliper, anyway I took some OO steel wool wrap it around a 3/16 wood doul, placed a 3/8 drill on the end of it and got after it . they now drop out at aleast where I can feel them through a .452 sizing die, seems to work fine.

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