Bullet casting - sizing problems

[Beemer-mark]

I using a Lee 6 cavity die to cast .451 bullets. Using 1/2 Linotype and 1/2 pure lead. Cast about 500 with no problems, they shot really well with barely any leading. Cast another 500 and now I have a major problem sizing them. Using the Lee sizer that pushes the Alox lube bullet thru the bottom. Most bullets go thru easy, some go hard and 3 didn't go at all. Had to drive the 3 out with a punch and hammer. Started mic'ing the un-sized bullets and most ran around 0.4545, some 0.458 and then a few up to .464. So now I know why they won't go thru, but what makes a cast bullet so big?

The best guess I can come up with is that the aluminum mold got so hot that it grew to .464. However that seems unlikely because if I start getting frosty bullets I touch the mold to a wet towel briefly to cool it back down. I use a thermometer in the pot and keep the lead around 550~600.

The other guess is that one of the mold cavities is oversize. However I didn't seem to have a problem with the first 500 I cast.

The one difference between the first batch and second batch is that for the second batch I dropped them from the mold to a bucket of water.

 

[m1gunner]

Water quench will harden the bullets and make them difficult to size.

If you do not control your alloy as to percentage of pure lead, your bullets will cast different sizes due to different rates of shrinkage characteristics of the different alloys.

Could also be one of your cavities in your mold is oversized.

 

[epj]

Water dropping the bullets will harden them more than air cooling. (assuming the alloy contains antimony) That said, I use a Lee six cavity and water drop the bullets. My alloy is pretty much straight wheelweights, which is somewhat softer than the mix you're using. You could probably cut the lino back to 25% and still have alloy comparable to WW metal. I'm using a Lyman 4500 to size/lube, but I notice some bullets take a little more sizing effort than others. BTW, unless you have a tight barrel, or tight chamber, you might conside sizing to .452. Generally accepted sizing is .001-.002 larger than groove diameter. In .45 Colt or ACP, this is typically .451. Some 1911 style autos won't chamber ammo with .452 bullets due to chamber dimensions. All the ones I load for will chamber .452 without difficulty.

Check out the cast bullet forum. More info there on casting than you could ever hope to have. Cast Boolits - Dedicated To The World Of Cast Bullets!

 

[Beemer-mark]

Hardness doesn't explain the size variation.

 

[epj]

No, but variation in tin content, mold temp, alloy temp, etc. will result in variation in bullet diameter.

Again, if I might invite your attention to the cast bullet forum, you can get a full and very learned explaination of this phenomena, as well as any other technical question you may have about casting.

 

[OKFC05]

I don't understand the temperatures you gave.
Is your thermometer marked in F, C, or K?
Pure lead melts at about 621F.
It should not be melting at 550F, but 550C is way too hot.

Linotype melts at about 500F, and pure linotype should be cast at about 550F.

Are you getting a thick oatmeal looking dross?
Linotype is typically about 12% antimony, which is 4 times what you need in pistol bullets. Also, high antimony hardens like crazy in water quench.
Whack one of the bullets with a hammer and see if it flattens or breaks. Too much antimony will cause it to shatter.
Melt some pure lead by eyeball and cast a few bullets. Measure those.

 

[NKJ nut]

It sounds like with your second batch at some point you got a spec of lead on the face of the mold and it held it open ever so slightly. If the mold had an oversize cavity you would have found that out with your first batch.

 

[BruceM]

I have a six cavity Lee mold which drops a bullet similar to the H&G #68. It too casts bullets in the range of .454+" when using straight wheelweights. I called Lee Precision in Hartford to ask them where to send the mold for replacement. I got into a discussion with their customer service which escalated right up the food chain to "Mr. Lee" himself. He informed me that the mold was not defective but rather the cherry used to cut the cavities was intentionally sized the way it was so that in the event that somebody was to attempt to cast this bullet with pure lead, the as cast diameter would be .452". After Mr. Lee enlightened me with those comments, I swore off all future Lee reloading equipment purchases.

These are the only bullets cast with wheelweights I have which you have to actually reef on my RCBS sizer-lubricator's handle to get thru the sizing die. With smaller diameter bullets, the difference in the co-effecient of contraction between hard and soft alloys may not make much difference in the as-cast diameter but as the sizes get larger, it definitely does.

Running cast bullets thru a sizing dies is not done to swage bullets down to the correct diameter but rather to make them concentric and to apply lube. The less swaging action the better with the ideal situation being no swaging at all. Whether heat treated, water dropped or not, the swaging destroys the hardened outer surface of the bullet's driving bands and will cause leading issues.

Anyway, I'm not surprised to hear of this issue with a LEE mold. If your bullets are really running as high as .464" in diameter but are not finned and/or severely frosted, possibly the pins and pin holes are worn. A spec keeping the mold from completely closing usually causes finned bullets.

Anyway, Rant Off.

Bruce

 

[Tell Sackett]

?????????????

It sounds like with your second batch at some point you got a spec of lead on the face of the mold and it held it open ever so slightly. If the mold had an oversize cavity you would have found that out with your first batch.

Ditto.

One other thing with Lee moulds is that the pins are known to get "sticky" if not lubed. I use bullet lube and carefully otherwise it gets into the cavities on the end.

I have had this happen MANY times before. Yes, I have had some problems with Lee moulds, mostly in the round nose variety. Their venting stinks. Had some that were exceptionally out of round too.

One thing to remember, the harder the alloy the bigger the bullet from the same mould.

You seem to be trying for a super hard bullet though, why? From a 45ACP at velocities to 1100fps, with the proper fit in the barrel, wheel weights alone are good alone.

There are lots of reasons to have hard bullets, don't get me wrong, just curious.

I have some 357Mag 158gr bullets that I am driving over 1800fps with virtually no leading. They are 80% wheel weights and 20% Linotype, water quenched.

I would find it hard to believe that for a 45ACP you NEED yours as hard as you are trying to get them. Just me though

 

[dave b]

I vote for the mold not quite closed, for some reason.

 

[primersp]

i have the same problems with all the lee molds that i have
all cast oversize i have a saeco sizer in 358 ,the bullet were so stick that i must drive out with a wise.
i have give all the lee molds
i have also a nei 2 cav 460-505 the bullets drpo at 462-464 i cast it with pure lead and a bit of tine to fludify
the best mold that i have is a aussie C.B.E in 44 bronze made
the mold is marked 432-230 grs it cast at 432 size and 230grs

 

[shortrange]

It sounds like with your second batch at some point you got a spec of lead on the face of the mold and it held it open ever so slightly. If the mold had an oversize cavity you would have found that out with your first batch.

+1 It does not take much lead on the faces to cause this problem. Lee molds must also be lubricated for reliable closing.

 

[Driftwood Johnson]

Howdy

Take your oversized bullets and measure them both across the parting line and along the parting line. If they are wider across the parting line than along the parting line, your mold was probably partially open. If they are uniformly wide in all dimensions, it is probably related to your alloy.

I have a bunch of the Lee 6 cavity molds. They can be a little bit tricky keeping the mold closed when you are pouring lead.

There are three handles on the mold. One handle on the sprue cutter, and a pair of handles on the mold itself. When you are pouring the lead, keep your hand off the sprue cutter handle. Only hold the pair of handles on the mold itself. If you are also squeezing the sprue cutter handle while squeezing the mold handles, the sprue cutter handle can lever the two halves of the mold open a bit, and you will get lopsided bullets that are wider across the paring line. It is in the geometry of the sprue cutter handle, squeezing it tends to lever the mold halves apart.

Grab your mold and try it, you will see what I am talking about.

As far as alloys are concerned, the person you talked to at Lee is correct. I doubt it was Mr Lee. Perhaps it was Patrick, I had a lot of conversations with him while I was designing a bullet that Lee produced the mold for. Generally speaking, pure lead shrinks the most when it cools, adding tin to your lead causes the bullets to shrink less when they cool. So another way to control your overall bullet size is to vary the content of your alloy. I have one mold that is a bit oversized, so I only pour pure lead into it, then the bullets shrink the most, down to the size I want them. For other molds, I add a little bit of tin, so that they will not shrink quite so much.

 

[BruceM]

"As far as alloys are concerned, the person you talked to at Lee is correct. I doubt it was Mr Lee. Perhaps it was Patrick, I had a lot of conversations with him while I was designing a bullet that Lee produced the mold for."

The point is that next to nobody would cast that bullet from pure lead. The standard for smokeless powder centerfire handgun bullets is Lyman #2 alloy or something similar. Even that alloy is not particularly hard. If you would tell me you use pure lead, that's be the first person I've heard of so..., this line of reasoning is totally absurd to my way of thinking. The person who I last talked to was definitely not named Patrick and this conversation took place at least 12 years ago. If this was a round ball, Minnie or Maxie ball mold, we wouldn't be having this conversation. Unfortunately, you cannot make a mold work correctly for all persons with all alloys . A mold which casts more that .0015" larger than the diameter needed for you gun with your alloy is fairly useless for high velocity handgun loads IMO and that's why this was my first & fast piece of Lee equipment.

Per RCBS's Cast Bullet Manual #1, page 13, a mold which will drop a .452" pure lead bullet (as designed by Lee) will drop a .4537" bullet of #2 Alloy or wheelweights and a .4546" bullet cast of linotype. Similar information can be found on page 87 of the NRA's Cast Bullet Publication by Col. E.H. Harrison (ret.) and page 58 of the Lyman Cast Bullet Handbook. Also consider that this is a mold cut with a new and not worn cherry.



Bruce

 

[Tell Sackett]

Just gotta use it to benefit you!

"As far as alloys are concerned, the person you talked to at Lee is correct. I doubt it was Mr Lee. Perhaps it was Patrick, I had a lot of conversations with him while I was designing a bullet that Lee produced the mold for."

The point is that next to nobody would cast that bullet from pure lead.

Per RCBS's Cast Bullet Manual #1, page 13, a mold which will drop a .452" pure lead bullet (as designed by Lee) will drop a .4537" bullet of #2 Alloy or wheelweights and a.4546" bullet cast of linotype. Similar information can be found on page 87 of the NRA's Cast Bullet Publication by Col. E.H. Harrison (ret.) and page 58 of the Lyman Cast Bullet Handbook. Also consider that this is a mold cut with a new and not worn cherry.



Bruce

Bruce,
I too have called, just within the last two years, and have talked to Mr. Lee. Not sure which one as there are quite a few. They seem to run to "man children"!

Pure lead: not in my smokeless firearms. Not because it has no practical purpose, being so soft but it is a bunch harder to get a hold of versus other ready made alloy, such as wheel weights. Besides, it would be just like driving swaged bullets. Too soft for the greater velocities.

One thing to think about though about the sizes from that certain mold. Say you get a "lemon" firearm so to speak, one that the throats measure .453" or so. Knowing what we do about Lee molds can help us! All we have to do is get one of their molds, run harder than normal alloy in it and VIOLA, bigger bullets that we can drive harder.

I just went through this with my 44Mag Marlin. The 1894 is notorious for having a big bore. Mine measured .432". My favorite mould would only throw .431" bullets with Linotype. I bought an inexpensive Lee 6 cavity mold and formulated an alloy that would cast above .432" from it. I came up with a pretty hard bullet that filled the bore of my rifle and shot the best groups with it ever with lead bullets! About 1 1/2" @ 100 yards.

So, knowing how a product will perform can help us when we get something that isn't quite up to snuff.

Just a little different perspective on the Lee mould thing. Best $40 I've spent lately!

 

[BruceM]

I understand what your saying about turning lemons into lemonade. That said, I don't need to buy cars which constantly pull to the left because I make predominately left turns.

My experience with bullet hardness vs velocity vs leading has been a little different than most I guess in that you can't make a bullet too hard because it will lead. What is important is having the correct diameter bullet for your guns bore and cylinder throats in order to prevent gas blow by. You can make the bullets so hard and brittle that they will not be engraved correctly by the rifling and this will cause accuracy issues. I have driven cast bullets made of 3:2 wheelweight/ linotype and straight linotype up to 1400 fps in handguns without leading and without gaschecks. They were not so hard they they leaded the forcing cone or bore. They must be sized correctly however.

I suppose now that I've made this statement of heresy, we'll need to debate the difference between clips and magazines or possibly, if it's safe to shoot cast bullets thru a gun with polygonal "rifling" (read Glock).



Bruce

 

[Beemer-mark]

Take your oversized bullets and measure them both across the parting line and along the parting line. If they are wider across the parting line than along the parting line, your mold was probably partially open. If they are uniformly wide in all dimensions, it is probably related to your alloy.

If the mold was even partially open by 0.001 wouldn't I have flashing? The bullets are not round, so I could agree with this but I find it hard to believe I wouldn't have flashing.

I realize that pure linotype alloy would cast large at around .454. I have bullets casting .464. That's 10 thousands oversize. I don't want to get into a discussion about hardness or much of anything except why are some bullets so far oversized.

The first 500 I cast with no problems were probably a little softer than ALloy #2, thus I had probably had no problem sizing them because they were soft enough. This batch, as an experiment, I cast as 50% pure lead and 50% Linotype. They must be too hard to size when 10 thousand oversized. However they should be less than .454.

 

[BruceM]

It's hard for me to believe that they could be .010" oversized because the mold is not closed completely without them being "finned" also. Overheating a mold or selectively attempting to cool it by touching a wet rag could have warped the aluminum blocks but, then again, I'd expect to see finned bullets.

I wonder if the bullets are becoming oblong and not even close to concentric for some reason. If the mold it too hot, the bullets may still be somewhat "gelatinous" when dropped or, if the blocks are warped, the defect may occur while in the mold for the same reason.



Bruce

 

[Driftwood Johnson]

"The point is that next to nobody would cast that bullet from pure lead. The standard for smokeless powder centerfire handgun bullets is Lyman #2 alloy or something similar. Even that alloy is not particularly hard. If you would tell me you use pure lead, that's be the first person I've heard of so..., this line of reasoning is totally absurd to my way of thinking. The person who I last talked to was definitely not named Patrick and this conversation took place at least 12 years ago. If this was a round ball, Minnie or Maxie ball mold, we wouldn't be having this conversation. Unfortunately, you cannot make a mold work correctly for all persons with all alloys . A mold which casts more that .0015" larger than the diameter needed for you gun with your alloy is fairly useless for high velocity handgun loads IMO and that's why this was my first & fast piece of Lee equipment."

Sorry, I have not figured out how to do quotes on this board.

Yes, I do cast some of my bullets from pure lead, others from a mix of about 25/1 lead/tin. These are bullets for Black Powder for the 45 Colt, 45 Schofield, and 44-40 cartridges. High velocity is not a concern. Black Powder does best with soft bullets. Yes, I do use the content of my alloy to help control shrinkage because Lee's tolerances are relatively broad. I seem to recall they consider +/-.0015 as being in tolerance. Lee does not cut their molds with a cherry, they use a boring bar in a lathe type setup. This may be why their tolerances are rather broad. As I said, when I designed the J/P 45-200 Big Lube Black Powder bullet, these are the conversations I had with Patrick at Lee, perhaps 4 or 5 years ago.

Yes, the sprue cutter handle can wedge the mold apart enough to make bullets oversize across the parting line. I discovered this the hard way. No, they did not leave finning behind, there was no evidence of finning, just fat bullets. Rather than poo pooing my experience, try it yourself. You may be surprised that this may be the root of the problem. Don't squeeze the sprue cutter handle when pouring lead, just grasp the two handles that are attached to the mold halves.

 

[Tell Sackett]

Bruce,
Harness issues agreed. Too hard = leading just as too soft or too small. 100% agreed.

Beemer,
Fins: not necessarily. Depends on venting/temperature. The air in the cavity has to go somewhere. If you have air escaping through the open mold, to a point, the alloy can set before finning occurs. Again, to a point.

Here is what I know experientially concerning Lee moulds. Their venting stinks. If it is a round nose mould, you will most likely have to "pressure cast" in order to get good bullets. If one of the alignment pins/bushings becomes sticky the mold will only partially close, maybe only on one end, usually the end closest to you, and cause out of round and oversize bullets.

I almost forgot about something that you need to check. The alignment bushings. I have had them pull out of the block because of poor lubrication of the pin and hold the mould open. The bushing should be flush or slightly recessed. If it isn't that may be your culprit. Sorry, forgot about that!