sprue cutoff ?

[Harpman]

just went through a couple hundred bullets, weeding out, I have a bunch this time where the sprue cut is, its not good, hard to describe, kinda like the sprue is being pulled out, not a nice slice I have indentation right where the cut off is, obviously not filled out, small tiny holes...any idea where I went wrong on casting these ones ?........using wheel weights about 940 degrees, that seems to be a good temp for fill out for me..new mold PJ, seems to be sharp...looks clean etc..I been going from the pot directly under a hair blow dryer set on cool, hold 10 seconds, they drop when the mold opens, no banging etc...but a bunch come out with this messed up sprue area.

[klausg]

Harpman
You're cutting them too soon; your temp sounds way high to me. Lower your temperature a bit, and slow down your pace. You can still use those ones with the torn sprues.

-Klaus

[Harpman]

Thanks....I'm gonna setup a clock, when I get a good cut, that will be my time to watch, I was thinking either too soon or late, I was guessing at the amount of time to hold under the blower.
Also wasnt sure if those dimples in the base would be good for match shooting.

[gray wolf]

I am not an expert like some here but I cast my share. I think I agree with the way to hot opinion. Like at least 200* to hot. That could make your mold to hot also. I don't understand the hair dryer so someone else will have to tell me about that. I would think that with the correct Temp your sprue should harden in about 10 seconds. At that time you should be able to cut the sprue's and drop the bullets.
Like I said I am not an expert and I am not trying to sound like one.
Just trying to help.

[powderburnerr]

PJ mould should work just right at 750 to 775 . pour it hold the ladel at the spout for a 5 count and when the spru changes color cut it ...wait 10 seconds and drop it .works every time...........Dean ,,,

[pumpguy]

I think Klaus hit the nail on the head. 940 degrees???? Good lord man!!!! I cast 25s, 30s, 32s, 357s, and 45s. None of these need anything over about 700 degrees. At 940 degrees, it is going to take about 5 minutes to cool enough to cut the sprue and the mold is going to stay way too hot. I did not see what size and type of mold you were using. Not that it would matter, but, are your boolits really frosty?

[MT Gianni]

I would invest in a metronome, find a loud clock, get some music cd's with a steady beat and find a rhythm. Get something loud enough to make and keep on a pace and your speed, bullets and effiency will all improve. Gianni.

[Harpman]

I come up with that temp, cuz the boolits fill out perfect, and fall from the mold when opened, sometimes they actually pop out...And I noticed I was casting high when that happen too...not frosty, but close....WW's seemed to cast better for me at high temps........the blower is to cool faster, I seen one of those comercial setups and noticed they pour, go under a fan, then drop..so I thought I would try it...I'll go back to a lower temp though now, and try again.

[pumpguy]

What size boolit are you casting? I have never had fill out problems with WWs, but, you might try adding a little bit of tin to help. Are you bottom pouring or ladle pouring? You might be casting a little too fast and clogging up the funnel. I have a bevel base mold that it helps me to pour on the side of the funnel and let it run in.

[454PB]

I agree with the others....too hot. I cast around 725 degrees with WW.

Try running two moulds at once, that will slow you down enough to eliminate the problem.

[Harpman]

Ladle, its PJ 45 cal...weigh in at 555.0- 563 grains, depends on mix. .not all the bullets do this, just some...so I'm thinking its the speed or temp, or both...I'll cast some more this weekend using this advice and let you all know what I come up with.

[JakeOz]

Harpman, please get a casting thermometer and check your temperature. You are getting dangerously close (if not already at it) for lead to start to vapourise. This is a dangerous place to be. I cast at around 650 degrees or maybe a touch higher. I do find that I get a better cast when the projectiles are frosty and this condition does not harm anything in any way, but you are way too hot.

I have a brass mold I use for 550 grain 45's and I find that if I get the mold HOT, it flows OK. As to the hole, you are either not letting enough lead drop and/or cutting the sprue too soon. Fill it up a bit more and slow it down a touch and you will get a more harmonious outcome.

Regards :drinks:

[EMC45]

I recently had to keep a melt super hot and the mold hot as well. I added some 50/50 solder to my normal pure WWM and that was a mistake! I couldn't get good fillout and no matter how fast I cut the sprue it always seemed super hard. I was using a Lee 160 gr. .309 2 cav Aluminum mold. The bullets that I kept were pretty nice and they are super hard. I don't really need super hard as the pure WWM casts adecent bullet by itself.

[leftiye]

Harp man, Do you have/use a thermometer in your lead? If your pot won't cast cooler, the temp gauge might be off. From what you've said about the casting, it sounds to be being done right. If the lead were really 950 degrees I'd expect muy bad frosting, and real long cooling times in order to not drop liquid boolits. As for the cratered sprues, you just have to let them cool a little bit longer. There is a place where they are soft enough to cut flat and smooth - hotter smears, and cooler leaves a bump.

[Harpman]

Well, I take that back it was 850 degrees, I had marked the thermometer and checked it again to make sure, I may need to give the mold more time to heat up before moving to higher temp too, I'm thinking I might have raced to determine it wasnt hot enough when I left 750 degrees and moved up. I usually just cast a mess of bullets to heat the mold tossing those aside.

[BOOM BOOM]

HI,
Don't worry about the lead vaporizing. No caster furnace I know of gets anywhere nere hot enough to do that. IIRC lead boils/vaporizes somewhere between 1,700-1,800 degrees F.
That said ,it is true you were casting a bit hot perhaps.

[shotstring]

Howdy folks!

Just joined the forum - have been reading the posts for days and just couldn't stand it any longer - had to jump in. Seems to be a pretty good group here.

I haven't cast bullets for 20 years or so, so I have to rack my brain a bit to remember anything. One think I do seem to remember though is that to turn out the best quality bullets in the fastest time involved falling into a rhythem that was established by the number of molds I was using. Started with one mold til it heated up, then added a second, and if things started to frost up, added a third mold to the lineup. Just filled up a mold, set it down, grabbed and filled another, set it down and grabbed the third one and filled it. By that time the first one was perfect to open up and drop its bullets - then refill and grab the second one for the same treatment. With 3 molds going, you get some serious production. They were H & G 6 cavity molds and made quick work of a pot of lead!

Anyway great to meet you all - looking forward to some great discussion.

shotstring

[fatelvis]

Welcome back to casting Shotstring!

[joeb33050]

If they look like this, you're opening the sprue plate too soon.

[eka]

Well, if you are getting perfect fill out and the bullets are dropping like rain, I would leave the temp. where it's at. That being said, I would use the rolled up cloth, such as a wash cloth, in water and cool the sprue plate on the wet cloth. That will allow you to keep working at a faster pace. Trial and error will show you how long to hold the mold on the damp cloth. Probably three to five seconds.

Keith

[Jon K]

harpman,

Dean hit the nail right on 750*-775*. You're too hot @850 (hot@850)+. Pour a few at high temp(around 800*) to start, or pre heat the mold on a hot plate. Watch the base, once it fills out nice the sprue cut will also look good, then you're up to temp. Then drop temp to 750*-775*I have several PJ molds(my favorite) and they work best @750*-775*.

Jon
:castmine:

[dromia]

Use Bull Plate lube if you need to run the mould and melt at a high temperature, it lets you cut liquid sprue with out smearing or base cavities.

Its the wonderlube for moulds, link at the bottom of the page.