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clodhopper
06-08-2008, 10:42 AM
This thread is for gathering the wisdom on this forum on how to overcome the problems with casting little dinky bullets.

My own observations. Warm mould, use hot lead, don't forget to add some tin.
Burned out a hot plate warming moulds, has anybodt tried a toaster oven?
radiant heat might work good on iron moulds, gotta be poisen for wooden handles. Maybe thats why God invented tin snips?
Keeping lead to hot cooks out your tin.
How have you overcome these problems?

miestro_jerry
06-08-2008, 11:08 AM
Controling for temp would help a lot for your lead, my thermometers are the Lyman type with a dial indicator on them with the temps maked off on them.

I make my casting alloy in a seperate pot that is cast iron dutch oven using a propane turkey cooker as my heat source. I can do almost a hundred pounds at a time.

I warm up my wolds on a hot plate that I keep in the shop, but is set just about low.

The toaster oven idea may warrant some exploration, but as will most of these things, energy management should take the lead in any doing any of these things. I can make my Lee pot too hot, my turkey frier I can push that to about 1,000 degrees F with no trouble, but we need to keep the heat and liquid metal in the 620 to 650 range. Maybe a little hotter. depending on the alloy.

Casting 223 bullets is realy about the same as casting other bullets. The time to cool the metal to a drop temperature may be the only difference.

Now I have find my toaster oven and try that this week.

Hope this helps.

Jerry

DLCTEX
06-08-2008, 03:31 PM
I warm my molds, Iron and aluminum, by dipping a corner into the melt and then wiping off the clinging lead with my gloved hand ( it should drop almost clean when the mold is hot enough). 15 seconds on aluminum and at least twice that on iron. DALE

cbrick
06-08-2008, 04:35 PM
http://www.lasc.us/Lyman%2044%20gr%2022%20cal-6.jpg

Lyman 44 gr RNGC sized .224" two cavity iron mould. Pot temp 700 degrees, clip-on WW + 3% tin.

Mould pre-heated on hot plate and the first 12 pours cast fast and discarded without even looking at them to assure mould temp is up.

After that the casting pace is a bit quicker than normal (for me) to keep mould temp up and they come out looking pretty good.

When pouring the lead don't look at it as pouring lead . . . look at it as pouring heat and with 40 or 50 gr boolits your not pouring very much heat, the amount of iron to absorb and dissipate that heat is far greater than with 200 - 300 - 400 gr boolits.

The only real difference for me when casting the little guys is extra care to be certain the mould temp is up to a good operating temp and then casting a bit faster.

Rick

mooman76
06-08-2008, 06:00 PM
I agree with what these guys have said. I might want to add though that is seems to be a little more common for small bullets not to drop out of the mould as well. The heavier they are the easier they are to release. But every mould is different and some release better than others.

Calamity Jake
06-08-2008, 06:05 PM
I do it kinda like cbrick, only lead temp is closer to 775° and cast with one mould only if the boolet is 25cal or smaller, preheat on an elect hot plate. There's no problem getting the mould hot enough, it's keeping there so I cast at a pretty good pace.
All of my rifle boolets are cast in a mix of 75/25 WW/Lino so I have never had to add tin.

montana_charlie
06-08-2008, 08:47 PM
Burned out a hot plate warming moulds, has anybodt tried a toaster oven?
Since a hotplate seems like the most natural device for pre-heating moulds, let's explore the "why" of your having burned one out while using it for that purpose.

First...Were you running it wide open with nothing on top to absorb the heat except a mould?

Was it the type with a solid metal surface, or the kind with the exposed coil?

Did it have a heat control with Low, Medium, and High settings?

Do you know how much heat it was capable of at each of those settings?
CM

deltaenterprizes
06-08-2008, 10:28 PM
For some 25 acp bullits I had to use pure linotype to get them to fill out properly.They are not that big so a little went a long way.

clodhopper
06-08-2008, 10:46 PM
It was the cheapest wall mart had, I had a circular peice of 3/16 iron covering the burner wich was like a regular electric stove. Probably better and cheaper to get an old garage sale hot plate. Had the heat setting on high.
Was outside, winter time and the hot plate did not last long enough for me to think about testing the temp.
I have been succesfull in casting the lyman 225-438 bullet illistrated by cbrick by dipping the mould in the hot lead, casting fast, and casting in warm air conditions.
The part about discarding first 12 pours without wasting time looking at them sure makes sense though.
Alloy was 20WW-1 lead free solder. (95% tin-5% antimony).
Still want to read about more about how everybody casts small bullets.

leftiye
06-09-2008, 03:18 AM
I have to use a mold heater while casting to keep the Lyman 225438 mold hot enough to cast good boolits. I even feel that it couldn't be kept hot enough with those little pills to cast well otherwise. I'm not calling anybody a liar, but I'm not interested in trying it without the mold heater.

oscar
06-09-2008, 05:26 AM
What would the temp. of the mould have to be? We get a thing around here called a cup warmer, to keep you mug of coffee warm. Looks like a small hotplate, guess about 3" diameter cannot be adjusted and have no idea how hot it goes.
oscar

joeb33050
06-09-2008, 07:41 AM
This is only about iron/steel Lyman RCBS etc molds, not Hoch style. 1 or 2 cavity.
Measure the length, width, height of a mold and calculate the surface area using those #s. Forget the handle grooves and the sprue plate.
Get some number of square inches. Ex 12
Now take the nominal bullet weight of one pour worth of bullets, in grains. Ex 2 X 180 = 360
Divied the square inches of area into the grains, get "grains per square inch", g/s.i.. Ex 360/12 = 30.
If the g/s.i. is between 20 and 40, the mold is fine and will cast O.K.
If g/s.i. is under 20, the mold is cold, needs a lot of heat to cast well. Harder alloys cast better.
If g/s.i. is over 40, the mold is hot, it takes a lot of time for the sprue to harden, sprue cuts tear,cooling on a damp sponge per Bruce B. helps as does a softer alloy. Shorter fatter ex pistol bullets cast easier. Longer thinner ex rifle bullets cast with more difficulty/time.

The solution to a troubling mold is to make it smaller or (the sprue plate) bigger.
Add heat propane torch or hot plate, or Bruce B.s cooling. Too hot, cast just 1 of a 2 cavity mold.

Making a mold smaller is a problem, thicker sprue plate can fix any hot mold.

joe b.

cbrick
06-09-2008, 07:48 AM
leftiye, I have the 55 and 60 gr RCBS moulds and they are physically bigger than the Lyman and need help staying up at a good operating temp. More iron to keep hot and still not pouring much heat. I use a propane torch set on low and hold the bottom of the mould to it every few pours. Kind of a pain in the hieny but it throws extra heat and works. My Hornet (currently my only 22 centerfire) shoots the Lyman better so I'm not using either of the RCBS moulds much at this time.

With the Lyman if my casting rythm is interupted for whatever reason, even breifly I need to use the torch also. If I can keep up the pace it will keep throwing good bullets. The whole thing seems to be as simple as the amount of iron to be kept at a good operating temp vs how much heat is being poured how quickly.

I've never used an aluminum 22 caliber mould but logic would dictate it would be considerably harder to keep hot since aluminum disipates heat so much faster.

Rick

44man
06-09-2008, 08:07 AM
I just don't have a problem with any boolit or size and don't need to do anything special except to regulate the temp for alloys.
However, the cheap Wall Mart hot plate did quit on me too. I checked the coils and they were good.
I found a thermal fuse inside that failed. The plate can't dissipate heat to a pot like it would under normal use.
I cut the fuse out, clamped the wires together and it works fine again.
If I were to buy a new one I would get the fuse as low as I could and insulate it so it would last longer.

Bass Ackward
06-09-2008, 08:48 AM
Sometimes thing just go fine with no problems and you couldn't tell that you weren't molding 30s. If you have difficulty using a bottom pour for small bullets and you are not sure why, try ladling them for awhile. You can ladle successfully about 100 degrees cooler with the same mix than with a bottom pour. This goes for about any mix.

And the weight of the lead in the dipper will force fill easier with the extra poured over the mold to maintain heat. You CAN force fill with a bottom pour on larger bullets but the mold will suck heat out of the spout and cool the mix too much in some cases making you scratch your head with small bullets when your pot is running wide open.

I don't like to force fill with a pot though, for safety reasons. IF you don't get the mold perfect, you can have a hot stream going every which way, and that ain't good. And we all get tired eventually.

Dale53
06-09-2008, 09:50 AM
I"ve used my hot plate (two burner with solid sheet metal burner) for several years. I set it on "medium" and heat the mould while waiting for the alloy to melt. The mould is just under casting temperature with normal alloys but about rigtht at temp with linotype. I often use linotype with small bullets. After things are up to temperature, I have no problem running near perfect bullets.

I use Lyman moulds for my .22 and .25 caliber moulds.

Dale53

montana_charlie
06-09-2008, 10:55 AM
What would the temp. of the mould have to be? We get a thing around here called a cup warmer, to keep you mug of coffee warm.
If a cup warmer could do it, think about putting a cup to your lips hot enough to keep lead from melting too fast.

Mould temp needs to between 300 and 500, while coffee cups can't be much over 120 drgrees.

But...I did use a cup warmer to build a nice heater for my Lyman 45 luber...
CM

GabbyM
06-09-2008, 11:32 AM
I've a hot plate here with the instructions. Says not for outdoor use. Maybe it's the wind that shock cools the unit??
A little under the low mark is plenty of heat on this one.

Recived some 6mm gas checks in the mail today. Now to cast up some of my Saeco #243 85 grain little pills. New mould that will be the smallest bullet I've tried to date.

I've some nice virgin 2/6 alloy that I cut with 20% pure lead. fils out groves real nice. News at six.

leftiye
06-09-2008, 03:04 PM
Pus one on what 44Man said about not having to worry about getting a mold the right temp if using a heater.

One way to keep adequate heat in a mold (reads high enough temp), rather, I should say know if your mold is hot enough is to get one a them IR thremometers. Your technique will affect your readings, but you will find out what's a desireable temp, and you can hold your molds to that heat. My molds like 327 degrees and up some. I just "shoot" the side of the mold.

GabbyM
06-09-2008, 10:25 PM
Not sure if a Saeco 6mm 87 grain bullet qualifies as little boolit. Seams little to me.
Made two little piles of boolits this evening. 270-150-RCBS and 6mm 87 grain. 270's don't qualify as little bullets. Ran the pot about 750*F.
New Saeco mould took a while to unwrinkled but after it got going it would drop the little boolits right out. The 6mm mould would start cooling off and 270 mould would start overheating. So I'd cast two 6mm to one 270 for a few cycles. They played well together. Both moulds were pre heated on hot plate.

Case in second photo is 243 Akley Improved. Plenty of room for powder. Have a new Shillen barrel on Rem 700 set in Fajen stock to try them out with.