Out-of-Round Boolits?

[Plumdog]

I picked up a used Lee mold (429-255) that seems to drop out of round. I measure .429 across the "seam" and .433 at 90 degrees from the "seam" using pure soft. Am I doing something wrong or could the mold be warped? I cleaned the block faces and tried again with same results. Looks like a well-used mold.

[MSD MIke]

I had a similar problem with a Lee Mold. 230 GR RN for 45 ACP cast so far out of round there was no hope of making it round by sizing. I generally have good luck with Lee molds, but this one was an issue. Also, giving the benefit of the doubt to the mold. I know you cleaned it but make double sure there is nothing on the mold face or on the pins (A spec of lead, since it's used) that could cause it not to close all the way. It takes very little to make an out of round bullet.

[Winger Ed.]

They can develop 'issues'.

I'm not a Lee guy, but give 'em a call, they may fix or replace it.
Customer service in this industry is about the best you'll find anywhere.

[Dusty Bannister]

Winger, I really doubt that Lee will replace a mold purchased used from another individual.

Is this the new style with the alignment pins or the old style with the V block alignment? Close the mold firmly and with the sprue plate moved aside, see if you can see daylight between the blocks. With the V block alignment, this may not be a valid test.

In order to really determine what is going on with the mold, check for debris or marks to suggest damage to the mold blocks as mentioned. Then use a micrometer to measure the cast bullets. With the bullet held to the mold seam is at 12:00 and 6:00, measure from 11 to 5, 1 to 7 and 9 to 3. This will show you out of round and how much, also mold blocks may shift out of alignment. The pin and socket can have a high spot from slamming the blocks closed, and the V block alignment can have roughness from lack of correctly lubricating the mated surfaces. Confirm the numbers and then folks will have a better idea what you need to do to correct the issue

[Bazoo]

It's pretty common for lee moulds. Being only .004 out of round isn't much of a concern. The issue is that the .429 is might not be big enough. I don't think any of my lee moulds make a truly round bullet, but if they are concentric it's of little concern.

I've had RCBS and Lyman moulds the same too.

[405grain]

"Being only .004 out of round isn't much of a concern."
You're joking right? If I had a mold that was casting .004" out of round I'd toss it straight into the dumpster. Why would anyone go to the effort to make their own bullets if they knew ahead of time that they weren't going to be accurate? Poorly made cast bullets are just a waste of components & time. Mistakes like this aren't on the caster's, they're the responsibility of the mold manufacturers.

[Wooserco]

Does running them through a sizing die make them round, as if swaging them round? I'm just curious if this makes them round.

[DDriller]

The only way to make them round would be a swage die. Another mold would be a lot cheaper.

[charlie b]

It may have been sold simply due to this problem.

[Texas by God]

I have an old TL 44-240 SWC Lee mould that likes a light tap on the bottom to square it up before the pour.
If I do that - the bullets come out just fine.
If I don’t - you can see the offset on the seam.


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[Bazoo]

"Being only .004 out of round isn't much of a concern."
You're joking right? If I had a mold that was casting .004" out of round I'd toss it straight into the dumpster. Why would anyone go to the effort to make their own bullets if they knew ahead of time that they weren't going to be accurate? Poorly made cast bullets are just a waste of components & time. Mistakes like this aren't on the caster's, they're the responsibility of the mold manufacturers.

Slightly out of round bullets shoot just fine as long as they are symmetrical. Poorly made would be rounded driving bands, rounded base, or filled out poorly on one side.

I had a Lyman 31141 that cast out of round about .005, and I got groups in the 1.5" range at 70 yards, which is the same as what factory ammo does out of my Winchester 94 30-30.

Does that mean that a bullet that is out of round is equal to one that is perfectly round? Of course not, but it's sufficient for most peoples needs and certainly not a waste of time and components, at least not for me.

[Bazoo]

I have an old TL 44-240 SWC Lee mould that likes a light tap on the bottom to square it up before the pour.
If I do that - the bullets come out just fine.
If I don’t - you can see the offset on the seam.


Sent from my iPhone using Tapatalk

My Ranch Dog TL432-265-RF is the same. I've had several older lee moulds like that.

[405grain]

Bazoo: It's not a reflection on the guy doing the casting, it's a problem with the mold maker. If they can't hold tolerances and produce a good product then they have serious quality control problems. This is why I don't use Lee molds anymore. Casting bullets isn't a waste of time, but the frustration of fighting with a poorly made set of molds is.

[lar45]

Make sure that the handles are not binding also. I fixed one that had a fleck of lead in it to not let the mold close.

[fredj338]

Just one reason I always size. It just makes everything more uniform.

[justindad]

Run it through your sizer. If the entire surface of the driving bands show sizing marks, it’s good enough for pistol shooting. If the sizing die fails to touch the driving band on one side of the seam then makes full contact with the driving band on the other side of the seam then your two cavities are not concentric and you’ll get a leaded barrel.

[Bazoo]

Bazoo: It's not a reflection on the guy doing the casting, it's a problem with the mold maker. If they can't hold tolerances and produce a good product then they have serious quality control problems. This is why I don't use Lee molds anymore. Casting bullets isn't a waste of time, but the frustration of fighting with a poorly made set of molds is.

I totally agree on that.

The amount of time I've wasted with Lee moulds (the ones that didn't work), and with the several Lyman moulds that gave me fits were not worth the cost savings over an accurate mould.

[BJung]

The mold halves might be out of alignment. Every time I drop my cast bullets, I tap the handle that attaches to the mold with a plastic mallet or piece of wood so the pins line up.

[JonB_in_Glencoe]

I picked up a used Lee mold (429-255) that seems to drop out of round. I measure .429 across the "seam" and .433 at 90 degrees from the "seam" using pure soft. Am I doing something wrong or could the mold be warped? I cleaned the block faces and tried again with same results. Looks like a well-used mold.

Plumdog,
Welcome to the forum.
I've owned a bunch of Lee molds over the years and maybe can shed some light on your issue.
First it's a rare thing to get a Lee mold that drops a perfect round boolit. They are usually 0.001 off, sometimes worse, but that is kind of rare to be more than that...and it usually doesn't matter that much for pistol boolits, when shooting at off hand at typical pistol shooting distances. I have some more thoughts, that may or may not apply.
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I hope you are using a 0-1" micrometer with slip clutch to measure them, because it's difficult to get repeatable measurements with a dial caliper or digital caliper...just the nature of measuring soft metal with thumb pressure.
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The location on the boolit you want to measure them, is on each side of the seam, not on the seam and 90º from seam. Measuring on the seam can give you a false measurement.
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Now casting with a 2 cavity Lee mold. The old style don't have alignment pins, they have extruded grooves. If those extruded grooves aren't lubricated, the mold won't close tightly, and due to the nature of those angled grooves, if the mold isn't closed tightly, the offset condition of the mold is accentuated. Now, the new style has alignment pins and just like any other boolit mold with two alignment pins, if they aren't set correctly, they can allow a mold to close are varying amounts of offsetness.
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Be sure to check more than one boolit when measuring of it being offset, to see if the condition is consistent or non-consistent.
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Good Luck.

[Plumdog]

Thanks all for the input. I'm getting .429x.431 or .432 after careful cleaning and lubing. Can see daylight between the mold halves. They are grooved along the one side and have pins the other way. I might try some dye to see any high spots, or just chuck 'em!