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<reverenddan>
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Anyone out there with experience using a casting thermometer please post your knowledge. What temperature do you cast what bullet? I know hot and cold, but since I just purchased a thermometer I am curious as to exactly what temperature others are using.
 
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Considering the many posts with reference to casting with the correct heat I would also be intrested in this sort of input.
 
Posts: 9619 | Location: Tooele, Ut | Registered: 27 September 2001Reply With Quote
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'Bout everytime someone runs out the Therm idea I gringe. I do understand why it's used, but can't find any application for what I do. And I regularly make bullets which weigh out to what I'd call match specs. My rattle here is only to encourage those not inclined to try one to not bother.

How to I accomplish this? Simple. First-- start with a preheated mold. How hot? Trial and error here-- cast is a game small, but important acquired skills earned by experience. I preheat on an electric stove-- medium low for up to 10 minutes. Dipping a corner in the alloy is fine-- just be sure not to overdo it. When the alloy stops sticking/forming a ball in masse your about hot enough.

Second-- the recommenders ya get are going to be different, sometimes much. Why? Casting rythmn-- the ebb and flow of the heat cycle of the mold, as compared to the same in the alloy. I use a Lee pot-- I preheat the ingots stacked on the dial area with one in the 'ready' position on the pot rim. Run the pot full minimizing alloy temp chg when adding that ingot. Coat the surface with generic kitty litter after fluxing. Minimal oxidation that way-- add back right into that surface is no problem.

Third-- your slugs shouldn't shine sans a lotta tin which is a waste. WW alloy is fine-- your goal is a sprue metal setting over a course of several seconds versus instant freeze up. Some run two molds alternately which works fine. Sorta a busy affair that way-- others cool the sprue with various methods to increase production.

My point is you still have to pay your dues and develope your own casting procedure. If you think a therm will help ya, by all means try one. Most will find it unused after developing their casting technique. Or-- put the money in another mold....
 
Posts: 1529 | Location: Central Wisconsin | Registered: 01 March 2001Reply With Quote
<reverenddan>
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I agree with Aladin that a good casting technique is the final solution to the thing. But...I think that a way to measure is the best way to accurately attain consistent results. Consider for instance when I was making ingots for the local sporting goods emporium, I was pulling WW's out of the garbage can and noticing the marked difference. Referring to Magma and their treatise on the cast bullet for commercial casters they suggest melting as large a batch as possible to negate the differences. All this to say that if I find a correct temperature for my Lyman molds verses my RCBS molds, a theremometer is the only truely accurate way to establish a consistentency without trial and error.

For me I am after spot on results without wasting too much time. I have turned casting bullets into a small (very) business and the more time I waste the less profit.
 
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Aladin,

Your remarks are (as usual) good stuff.

I have never used a thermometer in all the casting I've done for the reasons you have outlined.

I'd like to add, though, that the temperature of the alloy is important for viscosity/pour-ability of bullets.

For example, I have a couple molds that require the alloy to be quite hot in order to fill properly. Cooler metal, no matter how hot the mold gets, just won't work anywhere nearly as well.

Casting with the melt running so hot that the surface oxidation begins turning black requires a slower casting tempo for the tools being used. Thus two, sometimes even three molds may be in use at the same time with good success.

As you say, expierience will tell. If I ever DO get a thermometer I'll send you the numbers.

Good morning,
Forrest
 
Posts: 246 | Location: Northern Wyoming | Registered: 21 December 2002Reply With Quote
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I stick a thermometer in two of my 20 pound pots, while I cast with the third. One of the thermometers is a Lyman and the other is one I got from GAR. The GAR instrument is the far better.
When I am casting pistol bullets I'm working with two, or three, four cavity molds. The temp is set to 750 to 800 degrees. This temp allows me to throw the sprues back into the pot as I cast. This high temp also allows me to fill one mold set it down, fill another, pick up the first and empty it and refill, etc.
When the first pot is down to 1/3 or 1/4 remaining I switch to the next full pot and my buddy fills the first pot. By the time I'm working on the third pot the first is coming to temp and it will ready for me to start casting with it.
If I'm working on rifle bullets I fill a cleaned empty pot with ingots and set the temp to 700 to 750. Do the fluxing and such.
I'll have several ingot molds, upside down,or aluminum plate to set the molds on when the bullets begin to frost, to act as a heat sink. I work with one rifle mold, usually 45-70 or 375 two cavities. Each pot of lead is a production lot. They remain together until they are shot and no mixing with any other production lots.
Jim
 
Posts: 5797 | Location: Richmond, Virginia | Registered: 17 September 2000Reply With Quote
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I find it interesting how and why people use these things. I use one from Lyman. I find it gives me a repeatable starting point. I like it and will keep using it for that reason; a starting point. Things differ from time to time; alloy, mould and the the like. I'd be curious to hear who uses one the most; Dippers or Bottom Pours?
 
Posts: 17 | Location: Idaho | Registered: 21 December 2002Reply With Quote
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Aladin,
EXCELLENT POST, Bud! Lotsa' people have the ability to cast, handload, shoot and research. Few, indeed, have the ability to tranfer information and knowledge. You are to be commended.
 
Posts: 234 | Location: 40 miles east of Dallas | Registered: 21 December 2002Reply With Quote
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Arkypete,

Three 20 pound pots! And a helper too, Wow!

Interesting methods though.

I have a 90 pound pot, heated by a modified fish-cooker. This outfit is powerful enough for all casting tasks, as you may understand.

When comes time to run off some pistol bullets I bring the big pot up to temp, use it to fill the little 10 pound Lee and pour from the Lee as if it were kind of a glorified ladle, keeping it full from the big supply as the big gang molds depleet the Lee.

Good morning,
Forrest
 
Posts: 246 | Location: Northern Wyoming | Registered: 21 December 2002Reply With Quote
<reverenddan>
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Somehow this discussion has turned into Aladin's and not mine. I feel the original question is being ignored.

Do you use a thermometer? If yes why, and if you don't have you ever used one and quit?

I appreciate what Aladin said, I have found his remarks to be true with my experience but I am desiring information on exact temperatures (as exact as possible).

For instance; What temperature do you need with Lyman molds vs. RCBS? I know there is a difference through my own experience. What about Saeco? I don't have any of their molds but I would be interested to know about anyone's experiences with them.

Again thanks for the replies and keep the info coming.
 
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I've not found that the mold manufacture makes a difference in temp. I adjust the speed of my casting to the various materials of the molds. The Lyman four cavity molds require that I cast slower to allow more of the heat to bleed off in the heat sinks. The Redding four cavities are the standard since I have more of them. The couple of NEI aluminum molds are the fastest to work with because they heatup fastest and transfer heat to the heat sinks fast.
My buddy and I help each other to cast because we use the same calibers, mostly 255 grain 45 Colt slugs. Two guys spelling one another keeps the casting going and makes for a nice pile of bullets. The casting is a means to an end!
Casting a couple times a year we can cast enough bullets for the two of us to shoot to our hearts content.
While he is casting I can be sizing, or fire up the old Lyman pot and throw some 45 cal. 300 grainers for my lever action or some 350 grainers for my 45-70. As long as the conversation and coffee keeps flowing it's a pleasant day, as well as productive.
Jim
 
Posts: 5797 | Location: Richmond, Virginia | Registered: 17 September 2000Reply With Quote
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Bumble
I use bottom pour.
Forgot where I read about holding your mold with 1/2 to 3/4 inch of air between the sprue plate and the spout. I don't stop between individual cavities, I'll have a large sprue and a pile of alloy on the bottom deck of the furnace.
Jim

[ 12-25-2002, 06:53: Message edited by: arkypete ]
 
Posts: 5797 | Location: Richmond, Virginia | Registered: 17 September 2000Reply With Quote
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reverenddan - I use a 0-1000dF thermometer in a 20 lb bottom pour Lyman pot. Usually runs 750ish and a little more. It gives me a point of reference to come back to. Where Aladin has learned other techniques that are just as valid because they give consistant results. My next move is to drill a mould or two to measure with a thermocouple to see how hot they need to be and how fast they cool between pours - again a technical approach (because I can - not because it has to be done).

The key is recognizing that temperature (of the lead and of the mould) is a variable that needs to be controlled in order to get consistant results. People have been making good boolets with both low and high tech. methods.
 
Posts: 621 | Location: Virginia mountains | Registered: 25 December 2002Reply With Quote
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