Not Enough HEAT

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  • Last Post 15 June 2017
BigMan54 posted this 14 June 2017

Well I did it again. I got lazy & paid for it with A LOT of not filled out bullets.

I was going to cast some more LYMAN #311252-75GR RN. I had my old LYMAN pot already set up with an inch of Linotype already in the bottom, so I filled the pot with ingots. The LYMAN will not heat higher that 720degrees.  I figured if I cast fast enough I could keep the mold hot enough. I turned up the new hotplate to full & set the mold to preheat as I waited for the pot to come to full melt/heat. That hot plate with a cast iron diffuser plate will keep lead on it's surface molten at full heat. Works great for preheating molds & getting good bullets from the 1st cast.  I checked temp with my new LYMAN Digital Thermometer at start & it read 722degrees. So I figured too try it.

Well I started casting & got 5 real good ones from the 1st 3 fills. So I started casting & dropping into the quench bucket at my feet. I kept at it for 30min, then took A break. I refilled the little in the pot & put the mold back on the hot plate.

Came back in 15min. Pulled a few bullets outa the bucket.  WRINKLES, WRINKLES, all wrinkled. All I can figure out is that the mold was hot enough coming directly off the hot plate. But I couldn't maintain enough temp to get decent bullets.

Guess I need to get whacked in the head, every time I cast little bullets.  USE RCBS PRO-MELT POT THAT WILL REACH 850DEGRESS PLUS.

Old Lyman pot OK for big .44&.45's   

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun. Did I mention how much I HATE auto-correct on this blasted tablet.

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onondaga posted this 14 June 2017

BigMan54

Linotype melts at 462 F. That makes the ideal casting temp 100 degrees hotter at 562. Your 722 degrees is way more than needed in any case whatsoever for Linotype. It is a LOW temp bullet casting alloy.

The casting flaws you describe should be looked at under magnification. If the voids have rounded and have  shiny edges you have cold short from too low heat dynamics.. if the voids are crystalline, bubbly and jagged you have overheated the metal or the mold severely.

A close up image of a few of the worst ones would be easy for me to diagnose if you are not sure.

Voids can be caused by cold short, overheating, or flow restriction.

You using such a high temp with Linotype suggests you have overheat voids. You have a thermometer, try a pot temp of 562, the ideal temp for Linotype bullet casting. Casting at 3 drops per minute with a good rhythm is the ideal speed to match the ideal pot temp.

You may be severely over heating your mold for Linotype with the mold heating warm-up you describe. If your mold will balance or can be supported to rest on the top of your pot when starting with a new melt, the mold will be hot enough when the pot reaches 562 F.

Remember, Linotype is a low temperature melting bullet alloy.

Gary

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Dale53 posted this 14 June 2017

I agree with Gary...

However, regarding the top temperature possible with your old Lyman pot (I presume it is the old, eleven pound model?), if you remove the heat control knob, the thermostat is adjustable. I cast tens of thousands of bullets with my old Lyman (long since, gone). That  thermostat was also used in common steam irons used to iron clothes. It was fully adjustable from the low heat required for clothes to the high heat needed for bullet casting. Since I haven't had a Lyman for many years, and don't have one to look at, I cannot be more specific here. 

Good luck to you,

Dale53

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BigMan54 posted this 14 June 2017

Thanks for your comments.  But this is a previously discussed problem.  

I CANNOT get fill out on this particular mold (LYMAN #311252) unless the alloy temp EXCEEDS 775 DEGREES.

The "old" LYMAN pot is a MAG 20. I can't send it back to LYMAN to get the temp problem fixed because lyman refuses to fix any thing that is no longer cataloged. Even if it's only 2 years out of production.  I don't have the ability to fix it myself.

I was previously casting .30cal & 7mm rifle bullets out of this pot. I usually run my LINO at about 650 degrees using 2-3 1cav molds.

I switched over to the RCBS Pro-Melt this morning.  Using LINOTYPE at 775 degrees I cast 280 #311252 & 304 #356402 in about 45min. Those are good filled out bullets with 32 rejects total.

 

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun. Did I mention how much I HATE auto-correct on this blasted tablet.

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358156hp posted this 14 June 2017

Get yourself a PID, and integrate it into your pot by removing the original temp control and let the PID regulate your temps.

 

There's a lot of information out there on this, and it's going to be the only way to keep those old Mag20s going. Lyman pissed me off a few years back and I did exactly this. When your heating element goes bad, find the manufacturers information that's stamped into the element itself, then go to their website and order one by length. It will come as a straight piece, and you'll need to use a tubing bender to make it into the shape you need. Many of Lymans products these days come from China, the Mag 25 is reputed to be chinese as well. If you don't want to do this, there's a guy on Cast Boolits looking for a Mag20 for parts.

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BigMan54 posted this 15 June 2017

I can't even get the d**m cover off.  I'll continue to use it as long as it gets hot enough to melt at least 650 degrees.

If some one could explain to me how to remove the cover so I could access the inside, I would appreciate it. I can't fix it if I can't get to it. 

I keep reading about pids, but have no idea how to use/install one.

Some of us have barely the ability to operate/clean guns & load our ammo.

I' m by myself here, all my friends are either dead or retired away. I'm disabled, so I'm limited in what I can do. I cast for 1 hour & take 2 days to recover.

I'd just like to have written and/or diagramed instructions that I can use.  

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun. Did I mention how much I HATE auto-correct on this blasted tablet.

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onondaga posted this 15 June 2017

BigMan54

Does your pot work reasonably well? Will it stabilize +- 50 degrees or less when it has run an hour with bullet metal? Center the swing of the temp where you want it using your thermometer and you should be able to cast Linotype just fine. It is a forgiving metal to cast, much easier to work well than #2 or Hardball. Pure lead is the hardest to cast well, not Linotype. It pours like milk.

Try to get your Linotype melted starting low and see where you have to set the pot to get your melt thermometer to read 562 F. for Linotype. Then just cast with a good 3 drops a minute.

If your 30 cal bullets fit your rifle well they should easily handle START load levels of jacketed bullets of the same weight in your rifle, but accuracy velocity is usually a little lower.

Gary

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358156hp posted this 15 June 2017

Oops! I forgot something. Remove the knob from your temp control and look into the end of the shaft. You should see a slotted screw in there. This is what the factory used to set your maximum pot temp. Try turning it with a small screwdriver, I don't remember which direction will make it hotter, so you'll need to experiment a bit using your thermometer to keep track of your progress.

 

I haven't had a stock temp controller for so long that I plumb forgot about this.

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BigMan54 posted this 15 June 2017

Never had any other problems with this old MAG-20. That mold guide makes casting with LYMAN 2 & 4 cavity molds a cinch. I will try pulling off the knob & looking for that set screw. Thx for that info , 358156hp.

Sometimes I think I should get a small electric pot & dipper cast everything out of old single cavity molds. You get the most perfect bullets that way.

Gary, thx for your input.

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun. Did I mention how much I HATE auto-correct on this blasted tablet.

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