HangFireW8
03-24-2016, 11:58 PM
When you play with alloys while casting. I was trying to find out what worked with my new RCBS 30-180-FN mold, tossing in a few extra nuggets of monotype, and then cutting it back with pure(ish) lead and WW, and trying temperatures from 550F to 710F. I suspected some of the mixes were pretty high in tin, and I want to reuse the mix at some point, thus the weighing, to see just how far things had gotten.
http://castboolits.gunloads.com/attachment.php?attachmentid=164422&d=1458876531
The main problem was, poor fill-out on one side of the boolit, both cavities, same problem. Thus, playing with more tin. The cavities were ultra-clean, but I cleaned and checked them again.
Next I drained the pot and mixed up a batch of WW+2% Pewter (by weight) and that's the 193.5gr column on the right. These were all the "good" boolits from about, oh, 600. The other 500-some all had a shrunken side. I'm nothing if not persistent. It seemed like it filled out better at higher temps, but I couldn't do much there, the boolits stuck something awful at higher temps, too. That makes maintaining mold temp really hard, when it takes 2-3 minutes to bang out both cavities. Pressure casting (I have a Lee 10lb drip-o-matic) worked, and stuck boolits something awful, too.
After 3 sessions of this I was about to send it back to RCBS when I read the instructions, it said they use Linotype and had directions for ladle casting. I do ladle casting, on special occasions, but then again, sticking bullets, and I'm not going to mix up a batch of linotype for just one mold. I'm a WW+2% kind of guy.
So I go over all my other steel mold notes, and notice another mold with the same issues, fill-out and sticking at high temps (by high I mean 700F). I take both (the other is a 323470), Clover 240, medical swabs and my drill/driver, and got to polishing cavities.
Viola'! Both molds start dropping easily at 700F. For the first time in, ever, since I bought it in 2009, the 323470 was a pleasure to use, and I got a lot of useful boolits out of one session. The 30-180-FN produced a bunch of good stuff as well. All the 30's from this last batch (that I've weighed) all weigh real close to 193.5. That's the WW+2% Pewter, one of my standard mixes. Curiously the polishing changed the weight not a bit.
The moral of this story- buy custom maker molds, of course, but the other is, even if a steel mold is burr-free, well ventilated and absolutely clean, if it sticks boolits at higher temps, polish it.
http://castboolits.gunloads.com/attachment.php?attachmentid=164422&d=1458876531
The main problem was, poor fill-out on one side of the boolit, both cavities, same problem. Thus, playing with more tin. The cavities were ultra-clean, but I cleaned and checked them again.
Next I drained the pot and mixed up a batch of WW+2% Pewter (by weight) and that's the 193.5gr column on the right. These were all the "good" boolits from about, oh, 600. The other 500-some all had a shrunken side. I'm nothing if not persistent. It seemed like it filled out better at higher temps, but I couldn't do much there, the boolits stuck something awful at higher temps, too. That makes maintaining mold temp really hard, when it takes 2-3 minutes to bang out both cavities. Pressure casting (I have a Lee 10lb drip-o-matic) worked, and stuck boolits something awful, too.
After 3 sessions of this I was about to send it back to RCBS when I read the instructions, it said they use Linotype and had directions for ladle casting. I do ladle casting, on special occasions, but then again, sticking bullets, and I'm not going to mix up a batch of linotype for just one mold. I'm a WW+2% kind of guy.
So I go over all my other steel mold notes, and notice another mold with the same issues, fill-out and sticking at high temps (by high I mean 700F). I take both (the other is a 323470), Clover 240, medical swabs and my drill/driver, and got to polishing cavities.
Viola'! Both molds start dropping easily at 700F. For the first time in, ever, since I bought it in 2009, the 323470 was a pleasure to use, and I got a lot of useful boolits out of one session. The 30-180-FN produced a bunch of good stuff as well. All the 30's from this last batch (that I've weighed) all weigh real close to 193.5. That's the WW+2% Pewter, one of my standard mixes. Curiously the polishing changed the weight not a bit.
The moral of this story- buy custom maker molds, of course, but the other is, even if a steel mold is burr-free, well ventilated and absolutely clean, if it sticks boolits at higher temps, polish it.