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SCHUETZENBOOMER
01-01-2010, 01:19 PM
Got off to a good start for 2010....got up at 5:00 and smelted 175 pounds of sheet lead flashing that I scored FREE. I would appreciate opinions on how I should mix my alloys and why. I say "why" because I am new to the technical end of this and need the education. My sole intent is reduced load target shooting with my 45-70 & 38-55.

I now have the following in approx 2# ingots:

86 pure lead (BHN <6)
24 melted shot (BHN 13-14)
8 melted lino (BHN 21)
11 in a 5:1 mix of the shot and lino (BHN 14-14.5)

Not sure I understand the resulting BHN of the lino/shot mix, but it is what it is.

Thanx and HAPPY NEW YEAR!

grouch
01-01-2010, 01:42 PM
My 45 - 70(and a number of my .30 cal. rifles) shoot their best with 20 : 1 lead and tin. It should do anything you'ld want in either 45 - 70 or 38 - 55.
Best of luck Grouch

405
01-01-2010, 04:05 PM
SBOOMER,
Glad to see your still kicking and scrounging Pb!
Without an assay of your "harder" alloys kinda hard to use any formula for adding precise amounts of tin and antimony for a predictable outcome. Looks like your flashing lead can be considered pure lead.

I have a similar situation to yours. A lot of pure lead (about 1400#) and smaller quantity (about 200#) of unknown mixes of harder alloy- dating back 20-30 years of scrounging.

What I do and it works pretty well. Melt 3/4 pot full of pure lead. Add (usually in 1 pound ingots) harder alloy. Flux and get temp to maybe 800. Cast bullet or pour small test slug. Let cool. Wait. Check BHN. Keep adding small amounts of the harder alloy and repeating the above process until the your objective BHN is met. It takes time... patience is good :). Once you get to the objective BHN. You can either: 1) pour that into ingots and mark the BHN on the ingots and keep repeating above until you get a big stash OR 2) just cast directly from the pot until all used up. If I know that I want a bunch of one particular alloy mix then I'll keep repeating, pouring ingots, marking ingots to lay aside a very large supply of that one objective alloy.

One caution about adding any unknown type of harder alloy to pure lead--- the BHN outcome is not linear . You can add one pound to pure lead and increase the BHN 1pt. Add another pound and increase BHN 1 pt. Then without warning add another pound and jump the BHN 5pts!
That's why I go slow and add small amounts and check BHN after each addition.

mpmarty
01-01-2010, 04:22 PM
try this for some answers

prickett
01-01-2010, 08:08 PM
What I do and it works pretty well. Melt 3/4 pot full of pure lead. Add (usually in 1 pound ingots) harder alloy. Flux and get temp to maybe 800. Cast bullet or pour small test slug. Let cool. Wait. Check BHN.

If water quenching, does the BHN remain the same over time? Or, will it harden (or soften) over a period of hours/days?

IOW, if I immediately check BHN after water quenching, will that be an accurate indication of the hardness when I go to shoot a week later?

303Guy
01-01-2010, 08:12 PM
Check BHN. Keep adding small amounts of the harder alloy and repeating the above process until the your objective BHN is met.Valuable tip for me - thanks, 405. I have just applied it!:drinks:

largom
01-01-2010, 08:40 PM
If water quenching, does the BHN remain the same over time? Or, will it harden (or soften) over a period of hours/days?

IOW, if I immediately check BHN after water quenching, will that be an accurate indication of the hardness when I go to shoot a week later?


I have found that my alloy,water dropped needs to age at least 2 weeks before full hardness is obtained. Length of time from pouring to dropping boolit in water will also effect hardness. Water dropped boolits will begin to soften after a year or so.

Larry

405
01-01-2010, 08:47 PM
If water quenching, does the BHN remain the same over time? Or, will it harden (or soften) over a period of hours/days?

IOW, if I immediately check BHN after water quenching, will that be an accurate indication of the hardness when I go to shoot a week later?

I air cool cast bullets and don't water drop/quench nor do I heat treat bullets so maybe better answered by those who do. Most water dropping is done out of the mold with bullet still fairly hot but the water is continually warming... so would imagine the change over time would be small and maybe gradual-- that's not a definitive answer just an educated guess. I'd think the greater the temp difference between bullet and the water the more tendancy there would be for greater BHN change. May also depend on the alloy components??

With air cooled bullets, seems like they have reached equilibrium within 30 minutes to an hour. I don't think nor have I detected changing BHN over time with cast bullets handled that way. When sampling a batch of alloy, I let the sample slug air cool for 30-45 minutes then check BHN. I've checked those bullets months later and detected no change in BHN.