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shell70634
01-16-2017, 11:24 AM
I had small ingots of unknown sources that I had collected over the years. Some were COWW some from other sources. I mixed them up and made new ingots and cast a few boolits with em. BHN after 24 hrs is about 6. I also have some linotype ingots. I'm wondering if I should buy some of the super hard alloy pucks from Rotometals, the antimony shot from Rotometals, or the lino type to harden to BHN 12 or so. I plan trying paperpatching and maybe this mix would be good for that but I have more than I would ever use paperpatching.
I may just use it for gc'd hunting bullets. Is BHN 6 to soft for plain based bullets at 1500 FPS?

John Boy
01-16-2017, 11:50 AM
4 parts pure Pb plus 6 parts linotype = Bhn 15.0 that is Lyman #2
Yes Bhn 6 is too soft for 1500 fps. The above will work fine

Lloyd Smale
01-16-2017, 12:53 PM
I use a lot of 5050 pure/lino. It tests out about 15-16 bhn and water dropped about 22bhn.

RogerDat
01-16-2017, 01:17 PM
BHN of 6 is about plain lead hardness. Which is too soft for most uses other than muzzle loaders but it is a good base ingredient. The above recipes that use your linotype mixed with your plain lead are good place to start.

For pistol you can often do with less "sweetener" alloy because sub 1000 fps with good fit BHN of 10 is often used. So your 38's, 45 colt and ACP etc. will be fine wit a bit softer. If you powder coat you can take that same 10 BHN and get up into magnum or +P loads for pistol. Does depend on good fit. Lyman #2 or Hardball (BHN around 15 - 16) then powder coated can do 2k fps based on my own use. 50/50 Pb/Linotype is Hardball mix which has the same hardness as Lyman #2 with different alloy percentages, both good for rifle or magnum rounds.

Lyman #2 is 5/5/90 and Hardball is 2/6/92 with the middle number being antimony. Since Linotype is 4/12/84 you cut that 50% and you get 2/6 from the 4/12. Lyman #2 requires adding tin and lead to get 4/12 to be 5/5 and is frankly a PITA compared to making 50/50 hardball from Linotype. Hardball might be a touch less inclined to mushroom, and a touch more likely to break on bone in a hunting bullet than Linotype which has more tin and less antimony. Doubt difference is enough to matter but those that hunt using those alloys would know more than I on that subject.

Use the alloy calculator from the stickies in this forum and treat your BHN 6 as plain, can calculate how much of what alloy will yield what hardness and final alloy composition.

runfiverun
01-16-2017, 09:03 PM
test it again in a couple of day's you'll probably hit a 9 or so.

your alright for paper patching with smokeless to bottom/middle end loads with that alloy and even the 45 acp and many others would do very well with it too.
to get to a 11-12 or so on the bhn scale you only need like 1-1.5% more antimony.