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scarter
03-09-2013, 07:00 PM
I got about 10 of these out of 500 cast today. Not many, but wondering what is the cause? Is it temperature? or lead alloy? or what? any ideas? Thanks! (Sorry the picture is upside down)

skeettx
03-09-2013, 07:12 PM
1. Too hot
2. Add a bit more tin
3. Use two moulds for casting at the same time, fill one
set it aside, fill the other, take first one and cut sprue, dump bullets, refill, set aside,
take second one and cut sprue, dump bullets, refill, set aside, REPEAT :)

I set them down on an ingot, seems to work out well

Mike

johnnybar
03-09-2013, 07:31 PM
Bet the mold is way to hot. The tip of that bullet is likely located in the handle slot area of the mold and is less capable to wick away heat. Wait 3 or 4 seconds after the sprues freeze, before cutting them off, and if that takes more than a few seconds after filling, touch the base of the mold to a damp rag in order to draw off excess heat.

Walter Laich
03-09-2013, 08:15 PM
Agree temp is too high. what temp are you running your pot at? Mine is just above 700 but it's a bottom pour which needs to run a bit hotter than ladle pouring

John Boy
03-09-2013, 09:20 PM
Pot temperature when the sprue puddle frosts in 5 seconds - then cut the sprue plate

Your melt is too hot and your not letting the puddle frost - caster inexperience

500MAG
03-09-2013, 09:26 PM
I use a counting method after pouring to let the sprue puddle frost. You can get into a good rhythm and cast faster with better boolits. Oh, a PID helps to keep that exact temp.

btroj
03-09-2013, 09:41 PM
Mould temp is the culprit. Melt temp doesn't matter in causing this.
Slow down a bit in your rhythm, gives the mould time to cool a bit each cycle.

Key is finding a rhythm that keeps mould temp pretty constant pour to pour. Yours is too fast and mould temp is slowly climbing.

runfiverun
03-09-2013, 11:37 PM
you dumped them out of the mold too soon.
i do it with ingots on purpose so i can see the crystaline structure of the alloy.

scarter
03-10-2013, 07:15 AM
Thank you all very much. This is great advice. My lead pot was running about 700 but i could tell my sprue plate was getting too hot, therefore the entire mold was probably getting too hot. Thanks again. Scott

357maximum
03-10-2013, 09:42 AM
An internal metranome is just as important as a thermometer...in fact if I could only control one I would choose cadence over temp any day.

45 2.1
03-10-2013, 10:28 AM
Use a fan...................

Iowa Fox
03-11-2013, 07:07 PM
My quess, heat & alloy

exdxgxe4life
04-29-2013, 07:55 PM
Not adding anything new, but definitely either too hot, or you didn't let the mold cool. Could POSSIBLY need more tin, but I down it.

Horace
05-02-2013, 12:53 PM
A small computer fan works well.

Horace

gbrown
05-02-2013, 08:41 PM
Happened to me a couple of times, mold too hot. Just let the mold cool for a little while. Slow the casting down a wee bit and give the mold time to cool. Hollow points breaking up when I dropped them. You can also use a fan or a large sponge, or a wet towel laid flat on a concrete surface.