REAL Mold Issues

[rodwha]

I received my .50 cal 320 grn Lee REAL mold yesterday and tried casting. But I couldn't get a nice fill, and often had it plug up the orifice. So I took a drill bit and opened them up slightly and not get one nicely filled conical, but the other often has minor fill issues with a small portion of the base not quite filling properly. I doubt those will be accurate enough beyond maybe 50 yds so I toss them back in.

I also noticed that the better ones weighed 213-215 grns with pure lead (old lead pipe).

It was hard to get a good reading, but it appears as though the top driving band measured .510". Is that right?

I'm considering cleaning it back up, smoking it, and reoiling it to try again. Maybe I didn't do a good job?

[koehlerrk]

First question, was the mold hot? Second question, what temp was your lead?

[Maven]

"It was hard to get a good reading, but it appears as though the top driving band measured .510". Is that right?
I'm considering cleaning it back up, smoking it, and reoiling it to try again. Maybe I didn't do a good job?" ...rodwha

The one I had also cast .510" using "pure" Pb. Unfortunately, it was too small for the bore of my Knight Bighorn and grouped poorly. I've since sold it. As for the problem you're experiencing, I would do several things, among them cleaning the cavities again and smoking them. I'd also recommend making a slurry of Bon Ami and ATF, thoroughly coating a few reject REAL's and polishing each cavity with them: You'll surely need to clean after that. However, assuming melt temperature isn't the cause of your difficulties, I'd guess you have a minor venting issue. (I've had that problem with several new Lee Precision molds myself lately.) A [very] small bevel on the edge of each block should do the trick.

[curator]

When casting "pure lead" for muzzle loading rifles, I run my melter at about 750-800 degrees and add about 1/4% tin (from 50/50 solder). Using Lee moulds I have become a big fan of Bullshop's "sprue-plate lube" and pre-heating the blocks before casting. After getting the melt up to temperature I dip the front corner into the lead for exactly 2 minutes then begin casting. Usually the third or fourth bullets come out perfect and I begin saving them. Lee puts some amazing lubricant/preservative in their moulds at the factory. I scrub my new ones with Automobile brake cleaner and a stiff tooth brush to get it out--yours may need a good scrubbing as well. Personally, I have found the Lee R.E.A.L. bullet(s) to work great in just about any muzzle loading gun that has sufficient twist to stabilize them. A thick felt or card wad under them often significantly improves their accuracy.

[rodwha]

I don't have a lead thermometer, but my Lee pot is set at it's highest temp, and that's been plenty hot in the winter so it shouldn't be the temp.

I also set my mold on top of the pot to warm, but also cast several and remelt them to help ensure the mold is hot enough. It works with my much larger 5 cavity Accurate mold. So it shouldn't be mold temp either.

I'm thinking that my mold may not have been cleaned well enough as I rushed it wanting to get started.

My Lyman's Deerstalker (blued model with deeper RB grooves of ~.520") shot a 320 grn REAL very poorly (cast by another). It was tumbling at 50 yds as it keyholed and was way left and low. I placed a wad under the next two and they were near touching and just under bull at 50 yds. So I know these show promise as I hadn't tried adjusting my 70 grn 3F charge and got better results than with PRB's.

[mooman76]

Mine measures .517 at the top band. Since you are having trouble with fill out, it sounds like you still are not getting good fill out. I suspect you are not getting hot enough. Run the temp up all the way and try again. Pure lead takes more heat. Once you get good fill out, you can turn the heat down some until get a good rhythm going. Also pre heat the mould really good before you start.

[mooman76]

Preheat the mould by actually sticking it in the lead melt to include the tip of the sprue plate so it gets hot two. I usually do it for a count of 24 to get it hot enough.

[koehlerrk]

Okay, sounds like you're running plenty hot....

My suggestions:

Clean that mold again. Lee uses some very tenacious tubes when they cut them.
Flux your pot just before casting
Pre heat the mold by dipping it into the melt for 20-30 seconds
Cast 50 or so and see if it's improving

Last resort - add 1/2 to 1% tin to help fill out. I had to do that to make my Lee 360gr modern minie cast right. Good luck!

[docone31]

Your mold is too cool.Float the mold on the melt. Let it sit. After a fashion, check by casting. I go by six seconds to freeze. No bigge there. If it freezes faster than six seconds, it is too cool. Slower, it is too hot. I also soak my molds in mineral spirits prior to using. I liet them sit over night. As you cast, the mold will heat up, unless you are going slowly. That is a large mold, so, casting rejects alone will heat the mold up. I do not really prefer the R.E.A.L.s. I go to RB mostly. Just my way. I also use wadding under the R.E.A.L.s, it helps down range. I also adhere to the load listed on the sheet. Too much, and the R.E.A.L. can go every where.If the issues persist, you can cast a sheetrock screw in the sprue and take the castings and smear valve lapping compound on them. These you put back in the mold and spin. Won't take much to work. I had to do that on my first molds, before I learned the heat trick. I messed with the molds, sprue plate before I got them hot enough. If using lapping compound, cast six of them, and switch around which cavity they came from so the mold does not get out of shape. Left goes to right, right goes to left. Same cavity in same cavity. Go lightly, and mix them up.Use soft lead only. They can be a bear to load after lapping.

[rodwha]

I'm rather fond of the RB myself, but had to purchase a few cast REALs to see, and was greatly impressed by how much more accurate they were than my .490" PRB, though I had just finished breaking it in with ~200 shots, and haven't tried any other patch lube than the grape seed oil I was allowed to use as the olive oil was expensive and SWMBO would have my backside were I to use it.

My rifle shot the first REAL way left and low, and it had keyholed. But I had wads, and the next 2 were nearly touching and just low of bull.

When I first decided on a caliber for my first BP rifle I went with .50 cal as it seemed to have the most components available, and seemed it was just right for the majority of what I might possibly hunt, the biggest being axis or maybe a very large hog. And were I given the chance to hunt something much bigger, such as an elk, I could easily switch to a conical.

But I also want to purchase another barrel for my Lyman rifle meant for conicals so that I can attach a Malcolm style scope for hunts across fields that might give me a range of 150 yds or so. And so I'm inclined to try the REALs.

[Omnivore]

More heat is not always the answer. If your lead is turning color in or on the mold, it's too hot. That'll cause it to oxidize and fail to fill out.

Also make sure your pot spout, if it's a bottom-pour, is clear so you get good, rapid flow. Taking too long to fill the mold will result in poor fill-out and additional oxidation as more lead is oxposed to the air, and the high heat will exaserbate the problem. A paper clip or small nail, shoved repeadedly up into the spout as you pour some lead, will clear it out nicely.

I rarely use it, but I keep some of Brownell's Marvelux around. I used it the other day for the first time on over a year (as opposed to just wax or pine pitch) and it did help in that case, where I was having difficulty. Stir it in really thoroughly-- Your scrap lead may have some inpurities in it.

As indicated by others; pure lead is more difficult to cast than lead/tin alloy. It works great for round ball, but the features of the REAL and other bullets demand excellent conditions all around. Adding a slight amount of tin will help fill-out but won't harden the mixture too much.

If I ran my Lee Production pot at full throttle I'd get the super nasties - yellow and purple irridescense on the bullets and on the surface of the melt, dross everywhere and really poor fill-out. Ask me how I know.

So you have a bunch of variables to contend with: temperature of the melt, temp of the mold, purity of your metal, cleanliness of your metal, rate of pour, and surface conditions of the mold cavity and sprue plate. I'll add the possibility of mold lube migrating its way into your cavities-- I had that happen once.

It can get frustrating, but once you start dropping good bullets, and you will, KEEP GOING.

[rsrocket1]

A thermometer would really help you to see if your pot is really getting hot enough. I can keep the pot at 750 with the setting down around 6-7 and even at that setting, the PID is cycling it on and off. Poor fillout at the base makes me think your mold or the lead is too cool. Wrinkly bullets can be caused by too low a temp or oil on the mold. It doesn't take much and it takes a dozen or more pours to get it out, sometimes it never gets out until you clean the mold with hot water, Dawn detergent and a toothbrush.

At 750, dead soft lead worked great for my 50 cal 250g REALS