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Discussion Starter #1 (Edited)
I've always cast bullets with a bottom pour furnace, the only exception was using a dipper to pour some 300+gr bullets. I place the mould under the bottom pour furnace and let the lead stream shoot directly into the sprue plate opening, leaving a healthy load of lead on the top of the mould. Doesn't matter if it's a one cavity, dual, or a foursome, I do it just the same. I've cast about 3500lbs of bullets this way with good results, I realize this is a pittance in comparison to what some here have done. I've always had had good results with the bullets I've cast. Many where .45ACP bullets, which require little precision for 7-50yd shooting. Some are .35 caliber long range pistol and rifle bullets that have performed admirably out to 200 yds. They have ranged from .258 to .458, all with reasonably good results if matched to the bore/throat of the firearm in question. The question that I have is: What are the benefits/disadvantages of pouring bullets with the spout of the pot or ladel in the actual cutout in the sprue plate? As stated, I've never done it this way. Is there an advantage to this? Is there a disadvantage? Does it really make a darn bit of difference, so long as the bullets are accurate? I've read scores of info that advocate this way, and that way, and this specific way, but what I've done has always worked, as long as the diameter was correct. I've always been concerned with alloy temp and keeping the alloy clean. Frosting, an interesting subject unto itself. I primarily cast bullets with wheelweights, which I quench straight out of the mould. If they don't need to be hard, I buy them cheaply in bulk, swaged. What is the reasoning behind putting the spout or ladel, IN the sprue plate? What do you think about this matter?

The reason I'm asking all these questions is: I'm in the process of purchasing a .475 revolver and a .416 rifle. I'll be using cast bullets in the revolver exclusivley, and in the rifle for practice. I've had touble getting 300+gr bullets to pour out of the RCBS Pro-Melt, and the bullets for both these weapons will be in the 400gr range. If I use excessive alloy temp it works OK, but I like to have a little diameter for sizing.
 

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I find your question interesting. The first thing to say is use what works. I always pour from a bottom pour with 1/2" to 1" space between the spout and mould. It seems to me to allow the air to escape. I have one mould, 535 gr .45 Lyman, that doesn't fill out unless poured from 1" or better to use gravity to force the lead into the mould. I do use a dipper for casting BPCR bullets as they come out more consistant in weight. I also quench most of mine out of the mould with good results.
 

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I have only been casting for about a month for my .44 but about 15 years for my front stuffer. I always used a ladle to pour for the muzzleloader. I tried this with a double cavity for the .44 and ended up with lead all over the work bench. I find if I keep the mould about 1 inch below the spout on the bottom pour pot I can fill the mould very consistantly and control how much sprue I leave on the top of the mould. So far I get much better results witht he bottom pour pot then I do the ladle. I am looking forward to pouring some sinkers from this pot.
 

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Cast

Have cast for over 40 years from 22 to 58 minie balls, and have dipped and poured befor I could afford a bottom drop.
Am on my 4th. (I think) bottom pour, and have had no problems provided I had my molds hot enough. Distance of drop from a bottom pour can make a difference as noted by one of the other responses, but that is an easy adjustment with a couple of screws. As one of the others said if it works for you don't change.

Paul Nichols
 

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Ahhh, Pressure casting! The idea here is to use the weight of the alloy in the ladle (or pot, if bottom poured) to force any air bubbles from the mould cavity out through the moulds vent lines, which is how they're supposed to work anyway. I experimented with this for a while, and abandoned it. It can work as described, but can also cause other problems, such as having alloy freeze in the spout, causing an even higher rejection rate from improperly filled out bullet bases. With a bottom pour pot, at higher temps, you can also get whiskers on your bullets from alloy being forced into the moulds vent lines. While the whiskers usually come off readily, they're still a nuisance. You can also get fins on your bullet bases from alloy seeping between the mould and sprue plate. I now only cast with the ladle, I use a Lyman, modified for left-hand use, holding it over the pot while I pour, filling only one cavity at a time and refilling the ladle between cavitys, to keep fresh, hot alloy in the ladle at all times. I also allow all the alloy in the ladle to run off the top of the sprue plate to keep the mould as hot as possible, theoretically keeping the alloy in the mould molten longer, to reduce air bubbles, and allow the bullet to fill out better. ==Bob
 

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I'm with you Winchester,
I do the same. I used to use a double cavity mould for my 44/40 (200gr) and I never get both bullets to come out good. All because of pressure and temp. I do all casting one bullet at a time with a hand ladle. No problem. I keep the mould on the pot when not casting and the ladle in the pot all the time. Once the mould gets hot, all is good. But then it starts to get too hot and problems start.

I use a small Lee pot and I can kick the tem p up to 900 degrees. (more like 875) Sometimes I have to do that when casting the larger bullets (405-538gr.) Otherwise, I can not fill the entire cavity without bubbles or a rounded base.
 

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At 900 degrees (F) lead starts to vaporize. NOT good!!!!

Ordinarily you'd keep it at 700 or below.

If you are just going by the markings on the dial and not a good casting thermometer, then the dial may be wrong.

DON'T run your pot anywhere near 900 F! Major, major health hazard..... check your thermometer against another if necessary.
 

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Discussion Starter #8
I always try to run the coolest temperature possible. It gives less shrinkage and allows you to cast faster. It seems to me that at 900 degrees, aside from the toxic vapors that it produces, that you would have unacceptable shrinkage and very slow casting if using a steel/iron block.
 

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Mike gives good counsel! Make sure your casting temps are now higher than 875 degrees when working indoors, and then always make sure you have adequate ventilation.

The shrinkage factor may or may not be an issue when casting hot, depending upon both your alloy composition and the technique used for your sprue. Make sure that there is plenty of reserve metal on the sprue when casting hot, and you'll at least minimize the shrinkage factor to some degree.

Have fun, but above all protect yourself with proper ventilation, and keep that casting temp under 875 degrees!

I made mention on an earlier post of casting two-alloy composite bullets, and running both the pure lead and alloy VERY HOT, but that needs to be reserved for outdoor casting, with a slight breeze to help whisp away potentially hazardous vapors.

God Bless,

Marshall
 

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If you're having trouble getting square bases on long, heavy bullets, try loosening your sprue plate a touch. This apparantly allows the base to vent better, giving you square bases. I had this problem with 405 gr. 458s and this worked well. The sprue plate should be loose enough to (barely) move under it's own weight when the mould is turned sideways. Moulds that don't use spring washers can be a pain to do this with because the clearance between the mould and plate change as the mould heats, requiring constant adjustment for the first few several casts. My Ballisticast mould is a real offender in this regard. ==Bob
 
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