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derekmelton
02-20-2014, 12:47 AM
I've been looking but perhaps haven't looked hard enough for my answer, hoping someone can point me in the right direction. I've recently come into a LARGE amount of very pure, soft lead. I've been told it's 99.9% pure lead. My question is, can I cast pure lead boolits and powder coat them to keep from leading the barrel like crazy or do I need to add tin or something else to harden it before casting? This would be for 44special/magnum, 45acp & 38/357.

Thanks!

alfloyd
02-20-2014, 01:08 AM
You will most likely need to hardened the soft lead up to prevent it from skidding in the barrel and not griping the lands.
You will not need to make as hard as a bare cast slug, but soft will not work.

Lafaun

AverageJoe
02-20-2014, 06:19 AM
Derek,

Pure lead has a BHN of 5 or less, you would want to be around 8 BHN 38/357. A mixture of 1:20 Tin/Lead has a BHN of 10 according to my SAECO chart.

Walter Laich
02-20-2014, 10:36 AM
I believe his question is: will pc allow him to use the lead as is or does he have to harden it up a bit.

Beagle333
02-20-2014, 11:03 AM
He should harden it up just a bit for 357 and 44mag.
The .001"± coating of polyester provides friction protection, not shear strength. The grooves still gotta be able to grip something to spin the boolit, and magnums push it f a s t.

I'm pushing coated pure in 45 Colt and 38+P just fine though. 8-)
(Don't own a 45acp)

There are a LOT of guys who will trade you WW or even range scrap for your pure though, and you'll be set.:-D

bangerjim
02-20-2014, 02:24 PM
I mix and shoot ~9-10 bhn in everything I load in pistols. Rifles ~12-13.

And I PC everything. You need to consider deformation of the soft lead under the harder PC. Soft will deform when fired and could cause problems with accuracy. The thin coat will NOT compensate for a "tougher" metal under.

Get yourself some antimony rich alloy to use in your mix. And get a hardness tester to eliminate the guesswork! That is why everybody is hooked on the now-almost unavailable COWW's.

Oh......you ALSO need ~1% tin in there to allow good fill out of your molds. Soft will NOT cast well.
Tin does not add hardness very much at all, unless you add a lot of it. And at it's high cost today...."not prudent at this juncture"! It DOES lower the surface tension of the molten lead.

Have fun and welcome (finally) to the conversation!

banger

popper
02-20-2014, 02:56 PM
Soft will NOT cast well So true, but adding Sb will make it cast better as well as harder.

bangerjim
02-20-2014, 08:13 PM
You STILL need TIN! Ant will make them harder, but tin is the magic elixir that allows easy and complete fill-out of all the nooks and crannies!

You even have to add a little tin to COWW's to get them to really cast nice because there is, at most, 0.5% tin in there, if you are lucky.

banger

totalloser
02-21-2014, 02:43 AM
I agree sort of, but need is a strong word. Before PCing, I cast straight WW with no extra tin, and now use 3-4 parts pure to 1 part coww alloy with no tin added. Mold needs to be hot, and the pour needs to be abrupt (no dribble dribble pour) but done that way I get good mold fillout. It's trickier, but doable.

If I stumble across a swinging deal on pewter or tin my process definitely will change though. :)

AverageJoe
02-21-2014, 07:41 AM
Derek to answer your question, I would not cast pure lead due to all the reasons listed. If you have a large amount of pure lead, cutting it to make it stronger and accurate should be not too hard. Roto Metals sells some lead/antimony alloy (70/30) that is real good to make pure lead a nice shooting blend (I think I cut it 5 lead to 1 lead/antimony). My newest choice is foundry lead, I found a source that has remnants of foundry type that I cut my mix with. Then there is the old standby of wheel weights. Find a local scrapper yard and see what they have, I find crazy stuff at mine...70/30 lead/tin body lead, range lead, recently got a valve cover filled with a high lead/tin mix. It can also be a good source for brass.

TheDoctor
02-21-2014, 09:02 AM
Keep some of that pure if you ever plan on casting fora muzzle loader or shotgun slugs though.