What happened to these boolets?

[Elkins45]

http://i292.photobucket.com/albums/mm35/elkins_pix/IMG_0732_zps36984943.jpg (http://s292.photobucket.com/user/elkins_pix/media/IMG_0732_zps36984943.jpg.html)

The alloy is COWW, the mold is a brand new NOE .378 275gr RG2 HP. They were bottom poured from a Lee furnace at 6-7 and cast in a cool garage, but the mold was hot and was otherwise filling out well. This only happened when the boolet clung to the side of the mold without the HP pin. Opening the mold tore the boolet apart. I don't know if you can see it, but the one on the right is just barely deformed because it hung just a tiny bit.

It happened only occasionally (maybe every 25-30 casts) and always with the same cavity. I'm sure there's a tiny burr causing the boolet to hang, but why is the alloy falling apart? More importantly, what can I do to keep this from happening again?

[44man]

You were too fast with a hot mold, the lead never set up and cooled enough.

[Down South]

^^^ What 44Man said.

[Grump]

Your alloy is NOT one with a eutectic melt/solidus point, and you just opened it up too fast.

Your other "undamaged" boolits may have some dimensional driftage that you just haven't noticed.

When I've gone too fast like that with a Sb-Sn-antimony alloy that's about BHN 14-ish, pushing the dropped pistol bullets into the pile on the drop towel would sometimes break off a section of the front driving band.

If you really like the fill and frostiness you're getting, add a second mould to your routine and alternate between them. Then the boolits will have time to get truly solid before you open up the moulds. They also will shrink a little bit more and most likely drop more freely, regardless of your suspicions of a tiny burr being involved.

Or you could just drop your melt temp by at least 25°F, maybe a full 50°.

[stubert]

I've had ingots crack like that when I was in a hurry, You got to let them cool a bit more.

[bangerjim]

+10 on 44's & grump's thoughts!

I have had this haaopen to me with ingots and those BIG 300gn 45's when I get in a hurry.

Just slow down.....give the lead time to cool.....just because it LOOKS solid......it can still be "slushy" and do exactly what you have.

Thank goodness for "do-overs"!!!!!!!! :drinks:

Let us know what happened when you run cooler and run slower.

banger

[cbrick]

Has anyone mentioned the mold was too hot? :mrgreen: Ok, being a wise guy.

Yes, your mold and probably the alloy in your pot is too hot. Forget the numbers on the pot's dial, useless and meaningless and have no direct relation to melt temp. In addition to that as the level of the alloy in a thermostat electric controlled pot decreases the melt temp increases, all electric pots, just the nature of the beast.

Rick

[gray wolf]

Forget the numbers on the pot's dial, useless and meaningless and have no direct relation to melt temp.
What he said, get a thermometer.

[runfiverun]

I got nothing to add to the above.

good pictures though.

[Taylor]

Slow down,take your time.

[Larry Gibson]

When I've gone too fast like that with a Sb-Sn-antimony alloy that's about BHN 14-ish, pushing the dropped pistol bullets into the pile on the drop towel would sometimes break off a section of the front driving band.

The OP was using COWWs, not enough tin in that to form a decent SbSn alloy. Actual BHN of COWWs runs from 8 - 11. Adding 2% tin To most batches of COWWs does make for a very good SbSN alloy with a BHN, after 7 - 10 days of aging, of 14 - 17.

Otherwise as mentioned;

Mould too hot

Alloy to hot

Opening too soon

Larry Gibson

[454PB]

I agree with all the others.

A quick way to get things under control (after reducing the pot temperature) is to touch the FILLED mould to a wet towel for a second or two.

[fcvan]

*sniff* *sniff* you killed them :( They never had a chance.

All kidding aside, pretty hot when you dropped them. That's a good looking boolit and should work great when you get it worked out. Good luck!

[mikeym1a]

I have to agree with the others, the mold and/or melt was too hot, and had not cooled sufficiently before you tried to extract them. The first picture I saw I said, to myself, 'too soon'. I've done it myself more times than I care to admit, with boolit casting, and with ingots, as well. The cure is, as has been said, to slow down. I'll bet everyone who has responded has done the same at one point of the other. I usually utter harsh words when i do it, and tell myself to slow down. Anyway, continue on and 'Happy Casting!'. mikey :-D

[lwknight]

Wow! 14 posts in a row all in agreement.
You had best take that to the bank.

[s mac]

I have to disagree,that lead is rotten. Send it to me for proper disposal.

[243winxb]

bismuth to hot. :Bright idea: