Age harden point

[Junior1942]

How long after casting do cast bullets age harden? Do cast bullets age harden?

[Down South]

Hi Junior. I haven't tested any over long time periods simply because I haven't been casting that long. I have tested several batches that I've water cooled. After about two to three weeks the boolits seem to peek at around 20 BHN. That's testing with a Saeco tester.

[DanM]

I was thinking about starting similar thread today, but my question is whether to size and lube right after casting, or is it better to wait a week or so and then size?

[felix]

Dan, for a BR gun you want to size a boolit when it is at its hardest with spray lube. Then re-heat-treat and wait a year, more the merrier, for consistency throughout the batch. Then check and lube on the match day. For any other gun, don't size and lube until the day you shoot. It takes several hours for a boolit to change its hardness from sizing. ... felix

[DanM]

Felix....Did you mean several hours or several days?

[felix]

Those alloys which have a long slush stage, between fully hard and fully melted, take about three to seven days to get max hardness. Those alloys which have a short slush stage will take a month or more. Those alloys that have no slush stage are hardest (and softest) after they are cool. All alloys we shoot get hard fast to a peak, and get soft from the peak to several years. Given infinite time, these alloys will be the same (for the constituents involved) no matter how they were heat treated. So, to sum it all up, who knows how hard, or how soft a boolit is, until actually tested on the date of actual use for shooting or further manipulation. ... felix

[Calamity Jake]

How long after casting do cast bullets age harden? Do cast bullets age harden?

Depends on what they were cast out of, we know pure lead won't harden any, 20,30 and 40to1 will somewhat, a couple of points at the most.
ACWW will harden up to about 5/6 points over what they cast at in 3 weeks to a month and then not get any harder, at least with my testing.

My standard rifle mix is 75/25 WW/Lino, air cooled there 15, I have never WD any but oven heat treated for 1hr at 425° then icewater quenched are 20 at one week old, about 22 in a month and will not get any harder. If I up the mix to 50/50 I get 26/27.

So, do cast boolets age harden? yes they do, depending!

[buck1]

My testing has shown with my AC WW based alloys: The larger the cal ,the slower they cool and the slower they reach full or near full hardness. I was shocked how much it can vary. But its a true story! But as a rule...................
one month will get a lot of it, and two months will get most of it. A year will show slightly more hardening, but not much in my testing.
I have read but not tested that HIGH TIN content alloys will harden and then soften with time. But with the price of tin I dont plan to bother testing that one. .......Buck

[clearwater]

So I have some of Grandad's lubed and sized cast bullets from the 60's. Jacketed ones too for that matter.

Harder or softer now?

[felix]

They are at a steady state now, all natural, no artificial sweeteners. ... felix