Aluminum molds vs cast iron

[Corner Pocket]

I'm thinking of getting into casting my own. A friend advised me to stay away from aluminum molds. After reading through some threads on here, I see that some of you seem to like your aluminum molds and you seem happy with the bullets that they produce... Just wondering why someone would not want to use aluminum? Thanks!

Corner Pocket

 

[Floppy_D]

Beats me, all of my molds are aluminum. They heat up quick and don't rust.

 

[fecmech]

I think the Lee 2 cavity aluminum molds are somewhat fragile over the long haul but they are inexpensive and make good bullets. They let a new caster get his "feet wet" so to speak and gain experience and knowledge casting without it costing a fortune. The Lee 6 cavity molds are a step up the ladder and sure can make a pile of bullets in a hurry. I own and use Hensley& Gibbs, Lyman, Lee and RCBS molds. IMO the H&G molds are the cream of the crop and a real pleasure to use but you will pay dearly for them. For a fellow starting out the Lee 2 cavities will work just fine. Buy the 20 lb. pot in the beginning. If you end up getting serious about casting, the Lee 10 lb. pot will not keep up with 4 or 6 cavity molds.

 

[snuffy]

Just wondering why someone would not want to use aluminum? Thanks!

Because they're ham handed monkeys, that refuse to treat the molds with the care they demand! FACT! AL molds are not as rugged as ferrous molds. They don't last as long either.

If you're talking about the Lee line, they cost so little that when they wear out, the replacement cost is so little, you can get a new one. Also what you learned NOT to do with the first one, will result in the second one lasting longer. NEI makes some of their molds using AL. Those are some serious cash, so be gentle, they'll last a good long time.

Most of my molds are Lee AL molds. I do have a few Lyman's, bought so long ago that the Lee line wasn't available yet! Right now, the Lyman steel molds will cost 4X what the Lee line costs, then you have to buy handles,(the 6 cavity Lee's need handles as well.) Lee 1 and 2 cavity's come with handles.

 

[243winxb]

aluminum oxidiziation

Aluminum oxidizes, Iron rusts. Iron can be protected by oil. Iron is stronger. I like Saeco moulds. Pick a mold by the bullets style. They are not all the same. Some will have a tapered crimp groove. Some will have the grease groove cut to low to the base, effecting accuracy. Is it good to have a iron sprue plate riding on a aluminum mould block? View attachment 404218

 

[jcwit]

I see no reason to not use Alu. molds. Granted they aren't as strong as iron molds but with reasonable care they will last for a long time. I have one Lee mold that has over 10,000 bullets out of it, and its a 2 cavity.

One main reason I happen to like alu. molds is the light weight. Does make a difference if one has bad joints and lots of pain in their hands. If you're young this isn't a problem.

I use anti seize compound to lube the spru cutter.

 

[jerkface11]

Only the surface of aluminum oxidizes. It won't oxidize away to nothing.

 

[MMCSRET]

They must be handled the way the material dictates. I have several including one made of brass, all will make good bullets but the must be used as the maker dictates. You don't want to abuse any of them, but they all are designed to be used. I have molds that are about a hundred years old, I use them and they are great. Good casting!!!!!!!!!!

 

[Dean Williams]

Is it good to have a iron sprue plate riding on a aluminum mould block?

Why would it matter? Aluminum pistons ride up and down inside iron engine blocks millions of times with no ill effects.

After untold thousands of bullets from my aluminum moulds, I'd say there is no reason not to buy them. No reason not to buy iron moulds if they suit your purpose, either.

I cast over a thousand just this week with the first aluminum mould I ever got, (a Lee, about 20 years old), and it's still dropping the same great bullets. I have a cast iron set that is about the same age as the Lee, which also still casts great. I have moulds from Ideal (Lyman), Saeco, Lee, and others. None of the iron moulds cast better bullets than the aluminum types, nor vise-versa.

 

[243winxb]

Aluminum pistons ride up and down inside iron engine blocks millions of times with no ill effects.

That is because piston rings are in contact with the bore. They are made of wear-resistant materials, such as cast iron and steel, and coated or treated to enhance the wear resistance. Typically, top ring and oil control rings will be coated with Chromium, or Nitrided-possibly plasma sprayed or have a PVD (physical vapour deposit) ceramic coating.

 

[jgh4445]

I too have both iron and aluminum. I like and use them both. They both make great boolits.I do like to cost factor of the Lee.

 

[snuffy]

Is it good to have a iron sprue plate riding on a aluminum mould block?

Please make your point clear to those of us that are wondering just what it might be? If you mean that the lead smears when the sprue is cut too soon, that's a concern for a steel/cast iron mold also. One of the best solutions to that problem is something called bull plate lube sold by buckshot over on the cast boolits forum.

http://bullshop.gunloads.com/prices.html

Read his disclaimer on his homepage, he isn't an order today, get it the next day kinda guy, but his products are first class. The bullplate lube is an extremely high temp lube that stays put on the sprue plate to prevent the lead from adhering to it. It is also the best at lubing the hinge and the guide pins for any mold. Lee recommends bullet lube for this, some use lithium grease, the problem with those is keeping it out of the cavities. Bullplate is best in that it requires so little to do the job. I stick a Q-tip into it, let it drip off, then put a barely noticeable film on the sprue plate top and bottom. The same for the locator guide pins.

 

[Bula]

I like both, but the Lee 6 cavs have 2 HUGE benefits. The price is right and Big 'ole piles of nicely filled out bullets in a hurry. That said I still use plenty of Lyman and RCBS 2 cavity blocks too...You won't know until you try them for yourself. Goood luck amigo.

 

[243winxb]

Please make your point clear to those of us that are wondering just what it might be?

Iron on Aluminum would wear. Lube would be needed i would guess. I did use a high temp. oil on the Lee but didnt make it work a whole lot better. The only Lee mold i have is the Lee Key drive 12ga. If Lee moulds are all like that one, i would never buy another. It was misfited, burrs, alignment when closing the mold , way off. I have been casting a very long time, Lee is not the quality i am used to.

 

[snuffy]

OIC! I too have the lee key drive mold, mines a 7/8. It IS a pain in the behind to use. But it IS a hollow base mold, with a slot in the pin that forms the hollow base. Lots of things for the lead to cling to.

Add to that, from the looks of that slug you had a pic of in that thread about hollow pointing a lee key slug, you're using pure lead. And you aren't running it hot enough, lots of wrinkles. Pure lead is a royal pain to cast good filled out boolits with.

Do yourself a favor, try some "normal" type boolits from a lee mold, I'm sure you'll be pleasantly surprised.

 

[243winxb]

snuffy, i had the lee pot as high as the temp would go. Had to put the mouth of the pot right on the mold, like injection casting. The only way it worked. I was thinking it was trapping air. I have cast with a Lyman mould with the pin you pull, it worked ok. I just looked up Saeco molds, 4 cavity. $145 WOW and no handles, thats an extra $35. Lyman are better priced, the price on Lee you cant beat.

 

[sqlbullet]

The lee six cavity molds use an aluminum sprue plate. I lube the contacts points on my lee two cavity (steel sprue plate) and six-cavity molds as directed and have little issue.

I dropped a thousand bullets Sunday night while shooting the breeze with a friend who is starting out casting. He dropped about 300 bullets at the same time.

I can't speak to longevity at this point. I have one annoyance with my lee six cavity. The rear alignment pin falls out after the mold gets hot. I don't want to send it back, as the bullets it drops are great. I just have to keep my eye on that pin.

 

[ReloaderFred]

I have molds from Hensley & Gibbs, Ballisticast, Saeco, Old Western Bullet Mold, Lyman, RCBS, Magma, NEI, Rapine and Lee, plus some old ones without maker's names on them. I've got them in cast iron, aluminum and brass, and they all work, if the caster knows what to do, and does it. I even have two old H&G 10 cavity molds, but those are more work to handle than they're worth.

As to the discussion concerning hollowbase molds, you have to heat up the hollowbase pin properly prior to casting. If the pin is too cool, the lead hardens before it has a chance to properly flow and fill out the mold.

As Snuffy pointed out, getting pure lead to cast good bullets takes more effort. You have to finesse it, but it can be done. It took me a long time to get good slugs from the Lyman 12 ga. wasp waist shotgun slug mold using pure lead, but once I started heating the hollowbase pin, it became much easier.

I've got a mold for a .577 Snyder bullet that is hollowbase, and also requires pure lead. It's a pain to cast good bullets from it, but it can be done.

I've never had a steel sprue plate gall any of my aluminum molds, and I don't lube them. I've used Midway's Mold Release, but that's about it. Some molds cast better with the mold release and some cast better without. It all depends on the mold, just like some firearms.

Hope this helps.

Fred

 

[ReloaderFred]

sqlbullet,

You may be able to drill and tap a hole for a set screw to hold that pin in place. I'll look at one of my Lee 6 cavity molds and see if it's feasible.

Hope this helps.

Fred

 

[Floppy_D]

snuffy, i had the lee pot as high as the temp would go.

Out of curiosity, how hot were the molds? Aluminum molds warm up quick, but they cool quick too. I run wheel weights, and I cast some fantastic bullets, but the molds and the alloy need to be hot. I lay my Lee molds on top of a full pot, so that 1/2" is submersed in the lead. When I intend on casting, I'll pull the molds 30 seconds before I get going, and put 'em back on top when I'm done. Typically the bullets leave the open molds with a light toss of the wrist... if I get bad/sticking bullets, it's usually temp related.

 

[243winxb]

reloadedfred, great info, ty

 

[243winxb]

floppy d

Out of curiosity, how hot were the molds?

Very hot, i always start casting with the Lee pot at max. temp. I do know about warming the moulds, did that. Maybe next time i will take a torch to the base plug first, that might make the difference as reloaderfred has said. I still think the mould was trapping air.

 

[Floppy_D]

Very hot, i always start casting with the Lee pot at max. temp. I do know about warming the moulds, did that.

Then you got me.
That solves most of my problems. I hope ReloaderFred's ideas provide some solution. (I haven't cast for a big bullet like that, I haven't done anything over 240g.)

 

[ReloaderFred]

I hold the portion of the hollow base plug that contacts the bullet in the molten lead for a couple of minutes and that pretty much takes care of it. I just put it back in the already heated up mold and start casting.

Hope this helps.

Fred

 

[snuffy]

Wow, lots of info flying around while I was at work.

Fred, the lee key slug mold has the base pin integral with the mold, it's not a separate piece that slides in the bottom. So the opportunity to pre-heat it does not exist.

243, it sounds like you WERE trapping air. One bitch I have with lee, as far as their molds go, is the vent lines of the faces of the blocks are very shallow. Another thing, the sprue plate should NOT be in hard contact with the top of the mold. A very small gap is what you want, that allows air to escape that's being forced out of the cavity by the lead. This results in better base fill out. If you were holding the sprue plate hard against the top, then you took away that venting between the sprue plate and mold.

If I ever try holding the mold against the spout to cast pure lead, I get finning. IOW the lead travels into the vent lines looks like a cactus! If I really need pure lead boolits, I use a lyman bottom pour ladle. it holds about 8 ounces of lead, plenty for even the biggest mold. The head pressure is less that the whole 20 pound pot full of lead, so no finning, but still well filled out boolits.

Sometimes I cheat! I put ½ to 1% tin in the pure lead. It lowers the temp that it melts at, and vastly improves the flow ability of the lead. AND contrary to what most believe, it does not harden it much. In fact it makes it tougher, which interprets into the slug being able to withstand acceleration better.