Linotype?

[snaggdit]

I recieved a couple ingots of an unknown alloy from another member today. He thought they were high tin babbit. I cast a few Lee 175gr .401 TC boolits with it. They dropped at 163.2 and 163.4gr and .404 and .4045. I drained the casting pot (back into my muffin pan), cleaned it out and added a ingot of WW that I had melted and know they were pure WW, no stickons etc. Cast a couple with that alloy and they dropped at 180 and .403. I then checked hardness (fresh from casting). The boolits from the ingot of unknown alloy had a bhn of 19.3. The boolits from WW had a bhn of 12.1 using my Lee hardness tester. I compared the results to the info on this site, it gives lots of info.
CastBulletNotes (http://www.lasc.us/CastBulletNotes.htm)
It seems that it might be linotype. Here's why I think that. The bhn for tin according to this site is 7bhn. Linotype is 18-19. The ingots look just like the ingots I cast a few weeks ago from known linotype. very shiny sides smelted into a muffin tin. I had the same hardening issues with my linotype as I did with these ingots, ie. slow hardening. Also, if you look down the site to the chart labeled Expected (Approximate) alloy weight variation from bullets cast of linotype, you see a weight in linotype of 165gr. In WW, this would be 8.1gr heavier. This is close to what I found with the unknown metal and WW. 163.4 and 180gr. Not exact, though. A greater difference of +16.6gr.

I did have trouble with the sprues not hardening right away on the first set of boolits. I tipped the mold over the pot after about 5 seconds to tap the mold open and the sprues ran. Typically, when I set the mold over the pot to preheat, the first set of boolits usually harden the sprues almost instantly, so this was a suprise. The second set of boolits I let cool in the mold for 20+ seconds and the sprues finally solidified. They cast nice boolits, perfect fillout.

OK, I'm fairly new to this alloy stuff. Any of you experts want to chime in? Don't really have much more info to give you to help with the identification. Any guesses?

[Lloyd Smale]

linotype would be my guess. It could be a bit used and thats why your number is about 19. A good ammount of the lineotype i pick up is in that range of hardness

[snaggdit]

OK, thanks for the input Lloyd, no more input anyone? The weight discrepancy has me bothered. Otherwise, it would be a perfect fit!

[Cap'n Morgan]

There's an awful lot of different type metals: http://en.wikipedia.org/wiki/Type_metal

The page has some description of how various alloys react during solidifying.
A little detective work with a thermometer and a melting pot might give you a clue.

With the tin content varying from 4% to 18% and antimony 12% to 28% in type alloys,
your guess is as good as mine, but there's undoubtedly a lot of good stuff in your alloy:drinks:

[jhalcott]

I have quite a bit of USED linotype. It ranges in BHN from 18 to about 21. I mix it with some WW or pure(?) lead to get a 15/16 bhn alloy for hard bullets for hunting. Depending on YOUR intended use for the bullets you can use it as is! You can also maix it with ww or lead to get heavier but softer bullets. I have used high tin babbit to cast bullets in the past they often work quite well. It is a waste of valuable alloys though.

[snaggdit]

OK, thanks guys. Cap'n Morgan, thanks for the link. Good info.