I had a previous topic on my issue that seems to have been deleted. There, I was discussing how I could not get my Saeco #740 mold (casts a .410" dia., 409 gr bullet) to fill out completely on one side. The bands here where rounded and not real sharp.

I had tried everything to get this mold to cast properly (it always required casting at least 30 bullets before the bullets would fill out completely and this was after the mold heated up by sitting on top of the furnace or heated with a torch). Even while casting, slight breezes seemed to cool one side of the mold. I thought I had a contamination issue, vent lines not wide enough, bevel at the top not sufficient, too low a temp, etc. You name it.

I had all but given up when I thought that I'll crank the temp all the way up on the furnace that I use for this mold (24/1 alloy), or ~825 F, and try and cast as fast as I could when the mold appeared to be sufficiently heated. I would cut the sprue the moment it solidified and also not hold the ladle to the mold any longer than enough time for the lead to run into it. Clear the mold and refill as fast as possible. Low and behold the bullets started filling out completely! 

I normally wait a few seconds after the sprue solidifies and hold the ladle to the mold for a few seconds too with my other molds, but this mold like to be real hot.

I have now switched alloys between my two pots and the Lyman one, which I will now use for this mold, can reach 1,000 F! I'll probably cast at 875 or 900 F with this mold in the future. My RCBS pot can only go ~825 F and this will now be used for my 16/1, 429 gr, custom bullet based on a Postel/Snover nose and micro-money bullet grease grooves.

Just goes to show that some problems may require more than one change to correct. This one required not only a higher temp but also a faster tempo. Pheew! 

What are you using to measure the temp?  Typical Lead thermometers are not very accurate, so it might be that your real alloy temp is quite a bit lower...

Keep an eye on the Lead when you get it a little low in the Pot. Many years ago I used an electric Pot that just ran flat out, held about 20 Lbs. But when it got down about 2" from the top it could and would bring the lead to a low BOIL! once I recognized that I kept a few ingots on the top back edge and would slip one in
and already being hot they would melt in almost instantly and I could get right back to Casting. Getting a good casting process going has always worked well for me. No distraction, just get going and no looking the bullets over and rolling them around on the towel. That just allows the Mold to lose temperature and then you start seeing bases that are not quite filled out. I never had the one that has been posted with one side not filling out, but I use almost all Nose pour and so when I break the sprue off I roll the mold over and glance at the base, if I see any thing out of the normal it goes back in the pot. I now use a Gas pot and know just about where to set the flame for good bullets. I do know when I have it right when I get going and get slightly frosted bullets and occasionally indications that Vent lines are trying to cast. When you start casting vent lines you KNOW you cannot cast that cavity any better. Well all for now. Regards FITZ.
OLDTUCK

Old Tuck had the answer. Gas pots.

RSW wrote on Apr 14^th, 2020 at 11:43am:

I was going to make one but Midway had the RCBS on sale during RCBS rebate period for about the same price as the parts    I just bought it during the free shipping days.

When it comes to PID controller types does anyone know of a model that you just plug your furnace/pot into, rather than having to open the furnace up and connect the PID that way? 

I ask this because I have a glass-blowing kiln that has a PID that the plug from the kiln plugs into it and the PID just turns the pot on and off as needed. This type would be good if you have multiple pots and you would just need one PID no matter how many pots you had. 

My experiments indicated a thermocouple ion the mold maintaining constant pout temp will add more consistency than precise melt temp.

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Plug in,hook up thermocouple to the pot.