Foundry type

[buckndee]

I have located some foundry type that is supposed to be 64% lead, 24% antimony, 12% tin and a trace of copper. Is this a workable alloy for enhancing softer alloys? I am thinking adding 50% pure lead to equal something close to Linotype. Would it be castable as is for nearly J-bullet velocity?

[grumpy one]

I've collected a couple of hundred pounds of what is alleged to be foundry type, though in practice a lot of it is monotype and all of it is tin-depleted due to being kept molten and reused frequently. It is excellent as an alloying additive for most cast bullet alloys - my current favourite alloy consists of 6 parts WW, one part typemetal, and one part 3% tin, 5% antimony (my old bullet alloy, which I'm using up). The result is about 1.3% tin, 5% antimony, and it is 13.6 BHN three weeks after casting, if slowly air-cooled. However if the cooling is just the slightest bit fast it comes out hard (e.g. 24.5 BHN average if cast shiny, or 19.5 BHN if poured into an ingot mould).

So far as using pure foundry type as a bullet alloy is concerned, I've tried it and I didn't like it. It was way too hard for my Lyman 45 sizer-lubricator - seating Hornady gas checks into 25-30 BHN alloy just about broke the lever, and sizing down more than about 0.002" wasn't worth thinking about. Besides that it was very difficult to chamber a round that nose-engraved in the rifling, and if I made a mistake and leaded the barrel it was extremely difficult to remove (if it had really "plated on" to the bore).

You will find people on this site who know much more than I do about the use of ultra-hard lead alloys for bullets, though they disagree with each other pretty strenuously. My take is first, if you want something harder than linotype you may find it best to heat-treat a lower-antimony alloy, after sizing. Second, very hard bullets are quite unforgiving with regard to barrel-fit: they are reluctant to obturate and will probably gas-cut instead. So, if you have a beautiful fit in an ultra-smooth bore, this may be worth thinking about - but otherwise, probably not.

[475/480]

Yes ,a very good alloy to (help) sweeten other alloys.

Sean

[shotstring]

Also, be sure to check the hardness to see if it is actually foundry type. I just recieved my cabinetree hardness tester the other day, and it sure opened my eyes regarding my stash of linotype and monotype. Some items I assumed to be monotype actually tested out to be something closer to a 20 to 1 alloy. Other items I would have sworn to be monotype were simply good quality linotype.

[454PB]

The monotype I have measures 28 BHN. I've never knowingly seen foundry type, but it sounds like it would be a great alloy to enhance pure lead. A 50/50 mix of pure lead and my mixed montotype and linotype measures 19 BHN and makes beautiful boolits.

[hammerhead357]

I used to get foundry type or what the printers called hand set metal when I bought a lot of metal from print shops. I always mixed the foundry type with ww at a ratio of 50/50 to make lino. IIRC....
If I get a chance in the next day or so I will look at my notes and will try to post a reply. However I had to refine the copper out of the melt or it would freeze in the pouring spout and plug everything up. I would have to use a propane torch to get things going again untill I figured out how to get the copper out.
The method I used was to get the entire melt up to temp. then flux it very well and then turn of the heat and let the melt set until it had just started to solidify then skim the top of the melt. Sometimes I would have to do this twice to get the majority of the copper out of the alloy.
I will try to review my notes and be sure this is the entire process I used, I haven't done this for several years so my memory may be a little wrong here.....
This is just my experience and others may have different experiences.....Wes

[RexDart]

I recently scavenged several buckets of print metal from an older print shop. Most of it is clearly linotype: it's cast in rows of words, and I pulled it out of trays stacked on and around a linotype machine.

However, I also cleaned out the trays on the typesetter's bench, and got a great deal of "leading" material. These are the small slabs of lead used to put space between type. It's a different color, but it seems to be of a similar level of brittleness as the linotype.

Has anyone with experience with print metal used these "leading strips" before? Any idea of their composition?

[hammerhead357]

RexDart, I think the strips you are referring to maybe made of lino. IIRC the strips were pulled on a machine called an Elrod machine. But without seeing them I can't say for sure.
The Elrod strips will have marks on the side that are sort of like waves this was caused by the pulling and cooling of the machine. Can you post a picture of these strips?

Now as to the foundry type. I went back and looked at my notes and reviewed some old information from the CBA.
The ratio for ww to lino was 55%n ww to 45% foundry type. I would melt the ww at 650 degrees and when the melt was up to that temp. I would then add the type metal and let it melt then stir it well. Next I would turn the temp. down to 500 degrees and let the melt set for about 30 min. or so, it depends on the size of the melting pot and the amount of metal. But don't stir the melt, then after the waiting period skim the surface carefully. Sometimes I would then bring the melt back up to 650 or 675 degrees and then repeat the cooling- skiming process.
According to the information I have there are three different kinds of foundry type and the ratios were differnt for each one but I just used the above and it worked for me numerous times. Wes

[Ricochet]

There are several recipes for foundry type in the Metals Handbook, and I suspect there were more in practice.

[buckndee]

Thanks for the fallow up on removing copper from the foundry type. So at the 500degree reduced temp the tin should not oxidize out? If I can get my hands on this foundry type soon I will check the hardness with my LBT tester, hopefully the cabin-tree hardness tester will arrive soon.
Should the copper be remover from the base foundry type first or after alloying with other lead?

[hammerhead357]

Freeze out the copper after alloying the ww and type metal. I don't think that the tin will oxidize out at that temp but you will lose some when skimming the copper out. I never really worried about it very much. You will also lose some lead when doing this. I would also flux the melt well before turning the temp. down to 500.....Wes

[hydraulic]

I throw a few pieces in with WW's and get better bullets--filled out betteranyway. Have to stick a finishing nail up the spout once in a while.

[RexDart]

Can you post a picture of these strips?

Thanks for the info. I'll try to snap a picture tonight.