Poll: Best mould material

[Firebricker]

I have more iron moulds than any thing else but love my Mihec brass mould. My question is how come you don't see a lot of 4 or 6 cavity moulds out of brass ? FB

[tommygirlMT]

I have more iron moulds than any thing else but love my Mihec brass mould. My question is how come you don't see a lot of 4 or 6 cavity moulds out of brass ? FB

Easy to answer that one --- it's hard to find suitably sized brass stock in smaller quantities that's not "cold rolled" material. Cold rolled material if made into large blocks especially long narrow blocks like used in 4+ cavity molds will warp when heated.

Basically you need "hot rolled" brass stock material to make such molds and it's very difficult to obtain in the correct sizes in the smaller quantity amounts that most small mold cutting companies order.

Now if you were a big name brand company with a high enough volume and were willing to contract for large quantities you could get suitably sized "hot rolled" brass stock material.

It's an "Economies of Scale" issue in todays metal markets to get hot rolled brass in the right sizes you have to be willing to commit to purchasing very large quantities of the stuff to get it at an economical price.

[Firebricker]

Thanks tommygirl that explains a lot. FB

[Lead pot]

I prefer 18 carat gold!

How is that Prolate ogive bullet shooting for you? and what are you shooting it with?

Kurt

[deltaenterprizes]

There should be a poll of how many have used brass molds. Many here have never used them since in today's market they are few manufacturers and the cost is higher.

[Cap'n Morgan]

How is that Prolate ogive bullet shooting for you? and what are you shooting it with?

Kurt

I haven't tried the bullet myself. I made it to specs for a Belgian gent (member of this forum, by the way) It was designed for long range competition in his 500/450 No2 Musket.

[Lead pot]

I use that ogive in my .44-90 BN paper patched and it is a fine shooting bullet but it needs to be cast hard I use 1/18 tin/lead.
You make a fine looking mould, keep up the good work.

Kurt

[jdgabbard]

Iron by far. Once you get it hot, you're boolits are beautiful. Period.

[Artful]

I have in order I owned/used them Iron, Aluminum, Brass - Brass is my favorite - Iron second - Aluminum last - Only advantage of Aluminum is lighterweight molds.

[Greg5278]

I like the Iron molds, because they last almost forever. The downside is they are heavy, and prone to corrosion. Brass makes a nice mold, and lasts a long time.

Aluminum is my least favorite, but does throw nice bullets with less preheating. It is easy to damge if dropped, and will gall on the Sprue pivot unless it is dry lubed. It also is harder to get pins, and threaded bolt to stay tight. I made my own Mold blocks, and the Aluminum expands much more than other materials when reaching casting temp. The first Molds would drop out the Alignment pins when they reached the temp. The pins were precision pins, and the holers were drilled and reamed to size with Lubricant. Now I have to use oversize +.001 pins to keep them fixed. It is a problem, but once you learn about it you can fix it.

I do have one bronze Mold from 932 Bearing Bronze. I like it, but it can start to have the alloy solder to the Mold. I have to wipe down the cavity every 80-100 bullets. Brass doesn't seem to have the same affinity for soldering. I was going to make a test mold out of Aluminum bronze, but haven't gotten around to it. Aluminum bronze won't corrode, is almost as hard as steel, and won't solder to the bullet. It is really tough to machine though. I don't think any current Moldmaker would volunteer to make one. It is a very interesting material, you can check it out under the name Ampco bronze.
Greg

[neilin]

I like iron, maybe because I have used iron for more than 30 years. I do have an aluminum mold, that is doing alright so far. I have never used brass.

[MtGun44]

I voted for 'other' because I put the iron used by Lyman in a totally different category
than the Meehanite iron that RCBS uses. The RCBS dies are much more resistant to
damage than the Lyman dies. I have many of aluminum, lyman iron and meehanite and
prefer meehanite by a lot.

Bill

[ktw]

Seem to recall that Bass Ackward (or Old Fellar or ?) had a treatise on the ideal mold material being dependent on bullet diameter/weight/number of cavities. Something about the differential abililty of each material to hold or dissipate heat and how that quality varied widely from the 22 caliber to the 45 caliber ends of the spectrum.

Couldn't find the post but it would be worth reviewing again.

-ktw

[deltaenterprizes]

I am working on a copy of a Lyman 50 gr 25cal RN for 25ACP in brass right now. The iron one I had was hard to heat and I need to use pure linotype to get the bases to fill out. I hope to have the cavities cut and holes drilled to mount the handles and sprue plate and give it a try soon.

[Onty]

I woted for iron, but why not use stainless like 302 or 303? 304 is even better but harder and finicky (hard spots) to machine unless you use Carpenter Technology Project 70 or similar quality.

... The best[TM] solution would probably be a mold made of a material like Beryllium copper, which has extremely good thermal conductivity, and then keep the mold at an even temperature by hooking it up to a circulation system.

Could be, but damn thing is a poison, cancerogen wehen dust inhaled, so any shop that manufactures beryllium copper has to have special equipment to protect workers. I know that firs hand because I was ordering parts/tools made from it.

[Stage X Tuning]

First post so please bare with me.

Looking for the same info on what to us for my mold. im new to it and am also wondering why is stainless steel not on the list? i work for a MFG of an aerospace company and i have many CNC Lathes, CNC Milling (up to 5 axis) and the ability to make any tool for the CNCs. As well as just about any metal form Iron, Aluminum, Naval Brass, Bronze, Stainless Steel, Monel, Hastelloy, Inconel, to Titanium.

so what makes Iron best? i also work with lead a bit and i know that lead will not stick to S.S. for nothing. i know that some brass and bronzes are what we call solderable (ie like copper) and at lest with S.S. you dont have to worry about rust. Corrosion happens to Aluminum thats why most aluminum parts are anodized or plated.

but so you know im looking to make some 9mm, 40S&W, and 50BMG molds.

Thanks
SXT

[Firebird]

Commercially they don't use stainless steel for molds because of the material cost and the machining costs. Iron is much cheaper and easier to machine, aluminum is much cheaper and easier to machine, even brass that has higher material costs has much lower machining costs and brass molds look so pretty people will pay the extra cost, but notice that brass molds are only available from some of the small one-man shops, not Lyman, Saeco, RCBS or Lee. Stainless steel also has fairly low conduction of heat for a metal. While this is good for the sprue plate, it would cause a very slow rate of casting as you will need to wait much longer for the bullets to solidify than aluminum, brass, or iron molds.
I think Modern-Bond made some molds out of nickel blocks back in the twenties, but they soon stopped because of the high material cost.

[turbo1889]

As far as molds made from Stainless Steel go. I have a few that were made by a local retired machinist. A couple he made specifically for me and then after his unfortunate passing on I obtained a couple more in the estate sale.

They are 400 not 300 series and have cooling slots cut above and below the handle slots like those found on an air cooled small engine cylinder. Although I did not know it at the time when I obtained the molds I have since come to the understanding that there are certain grades of 400 series that are available as "hot rolled" stock where as 300 series is apparently only commonly available in "cold rolled" stock which can/will warp when heated if made into long narrow mold blocks like the Lee 6 cavity molds, the Lyman 4 Cavity & 7+ Cavity Armory molds, and the Saeco 3+ cavity mold blocks. Supposedly, you can't usually do anything bigger then a two cavity block with cold rolled material without having problems. I have been told this problem also applies to brass molds as well since brass bar stock is almost always cold rolled.

Also, as I understand it S.S. work hardens during machining. I don't know exactly what that means since I am not a machinist myself but I understand it makes the machining process a real PITA for cutting mold cavities.

I wonder if there is any reason why one couldn't make some form of "Leaded Stainless Steel". It is my understanding that leaded steal has excellent machining properties and makes excellent boolit molds.

Any reason why both Chromium and Lead could not be alloyed with Steel at the same time and then hot rolled to produce a corrosion resistant easily machined material without any heat warping problems ??????

[MBM]

I used to think Iron was the only way to go. Then Bernie Rowles at Old West Molds introduced me to Brass. There are some down sides to brass. You can not lap the mold like you can an iron mold and you need to handle with care because they are more soft than iron. With that being said, I still like brass best. I like the way they cast and now that I'm making molds, I like the way brass machines.

[45-70 Chevroner]

For production longevity obviously iron is the best. I have never worn out an aluminum mold and they are easier to handle bacause of the weight. I like Lee molds, they work well for me and the price is right. I have one custom mold by NEI that I bought about 20 years ago, for my 94 32 Win Spl. It is a great mold. If there was anything wrong with aluminum why do so many mold makers use it for expensive custom molds? I would be willing to bet that Veral Smith would guarentee his molds for thousands and thousands of bullets, with proper care. I can't belive anyone would not take care of thier molds even cheap ones.