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jimlj
09-22-2021, 09:13 PM
I recently acquired some Linotype I'm mixing with soft lead and some range scrap I have. I haven't had any tested so I don't know what the alloy actually is, but my cave man testing tells me it will bend some than snap. The lead I have will bend but not break.
I thought I'd do some experimenting with the lead I had in my pot. My 20 pound pot was about half full of the soft/range scrap. I didn't weigh it, but added a hand full of the Linotype and cast a hundred or so 125 grain boolits. They came out nice, perhaps slightly better defined than the soft/scrap boolits I've done in the past. Today I added enough Linotype to fill the pot about half full again and cast a 100 or so more. These also come out real nice, perhaps slightly frosty (PID controlling temp. 712* F). With these I noticed the sprue cuts way easier than before. A very slight tap and it's cut. I haven't tried any yet but I'm guessing they are quite a bit harder than the last batch.

Question... Can I add too much type? If I got to *pure* Linotype will it cause problems? How do I go about finding a good mix?
A bit more information.... Right now I am only casting for 38/357 and 9mm. Since I started powder coating I have zero issues with leading, even with the soft lead I've been using. In the future I plan to cast for my 30-30 and '06 mouse fart loads.

BNE
09-22-2021, 10:12 PM
You can cast straight linotype if you so choose. They will be pretty to look at.

Probably will also weigh less, be a different size and be much harder / brittle than you need. I don't think you will hurt anything on your gun.
Just a waste of Tin and Antimony rich alloy.

My 2 cents.

BNE

dondiego
09-23-2021, 07:49 AM
Try a 3 to 1, soft lead to Linotype ratio and see how that works out for you.

Larry Gibson
09-23-2021, 08:09 AM
The "frosting" may be more from too much antimony in the mix than too much heat. Linotype has a large percentage of antimony in it compared to the tin as does most "range lead". What is wanted is a balance of antimony to tin not exceeding 5% of each. Mixing the linotype with the range lead only acerbates the imbalance of antimony to tin.

For a much better alloy for your purposes you might get some tin (pure or from solder or pewter). Then mix the linotype with soft lead at 50/50. then add 2-3 % tin to that. That will then give you an excellent base alloy that will cast excellent bullets. With AC'd bullets the BHN will be in the 12 - 15 range and it will WQ to 18 - 20 BHN. For handgun, mousefart and 30-30 bullets it can be cut (softened even further by mixing that "base alloy" again with the soft lead at 50/50.

With the range lead you might add some soft lead at a 3 -1 mix (range lead to soft lead) then add 2% tin. That will also then cast excellent bullets for your purposes.

Wilderness
09-23-2021, 08:47 AM
You do not say if this if your first casting effort with this mould. If it is, then please ignore what follows.

If you have already produced some bullets that perform as you wish, then the WEIGHT of those bullets can be used to enable near duplication of the original alloy, or to fine tune an alloy that is nearly right.

What you will need to know is the weight of bullet produced by each of your constituent metals, i.e. lino, range scrap, other scrap etc. This includes metals fortified with additional tin as per Larry Gibson's suggestion. The bullet weight from each metal is determined by casting 20 or so bullets with each, selecting some good ones, and weighing them. Typically, I weigh five x 170 gn .30-30 bullets (my balance goes to 1005 gns) to get an average weight. If I have enough good bullets I will weigh two or three sets of five.

From there on it's straight maths. If your lino makes a 164 gn bullet, your range pickups make 178 gns, and the target is 170 gns, then the mix will be one part of lino (6 gns under target) and .75 of a part of range pickups (.75 x 8 = 6). If mental arithmetic is too much, then you can set it up as a spreadsheet.

Each time I batch up some metal I do a calibration cast while I have it melted, and label the ingots with the bullet weight. After a proper casting session I empty the leftovers into the ingot moulds and likewise label the ingots. Mixing up the next casting batch is then just a matter of deciding how many ingots from each source are required.

243winxb
09-23-2021, 09:20 AM
First- The sized bullet diameter must be correct for the gun. I would avoid alloys that are close to pure lead. Scrap or scrap with linotype do ok for target shooting, in 9mm , 38/357, 45acp, 44mag. For me.

The close to pure caused feeding problems in my 1911 Colt Gold Cup 45acp. The nose deformed on the feed ramp & a few stuck there. Never a problem before. https://www.thehighroad.org/index.php?media/alloy-makes-a-difference.4081/full
Note the weight difference between alloys.

B R Shooter
09-23-2021, 10:34 AM
I mix 30 pounds of type with 5 pounds of pure lead for rifle bullets.