Adjust the flow rate on my bottom pour pot

[oneMOA]

I am a rank newbe and after purchasing a fine Browning BPCR rifle (My first rifle in 45-70 cal) and deciding to try my hand at reloading, here's my question. Today as I fire up my RCBS Pro Melt for the first time and begin to melt some lead I have on hand, I starte4d out by making ingots in a Lyman 1# mould. Naturally since I have purchased a Lyman 535 Gr Postell mould, I decided to try some boolits, just to see how they turned out. I seem to be having an issue with the flow adjustment on the pot. What should I be looking for with the flow adjustment. Obviously to much and the overflow spills out over the mould, but my boolits in this trial run were not filled out.....wrinkles and such. I may have more than one issue here but in trying to eliminate one thing at a time, how important is the flow rate from the pot towards making good boolits?

[MT Chambers]

To control rate of flow on the RCBS, lift handle up less then the full amount, it will take some getting use to, sounds like your melt and esp. your mold is too cold. Preheat mold on hotplate of even on your melter, or prepare to cast many wrinkled bullets before your mold comes up to the right temp. and starts to drop nice bullets.

[Le Loup Solitaire]

Molds need to be pre-heated or else you have to cast for a while to get them up to working temperature. Its somewhat of a nuisance to watch a long string of wrinkled bullets to do that. With the alloy and the mold at the correct temp it is not difficult to adjust the flow with a Pro-Melt. Normally you do not want a heavy flow/stream that will swamp the sprue hole as this will interfere with the flow of escaping air from the mold cavity...a stream diameter somewhat less will suffice. Not letting the air escape will produce wrinkles or poorly filled out bullets. With a large bullet of 500+ grains a special situation has to be observed....if the stream/pour is too small then the nose section of the bullet can start to set-up before the base of the bullet is filled out....so you have to adjust the pour to avoid this. It takes some fine work to get this right...+ some patience. Overflow just makes a mess, but some is necessary once the mold cavity is filled because you need a generous puddle on top of the sprue plate to allow for shrinkage and the pulling of extra alloy into the cavity. If you don't do this, then you will risk...and get voids in the bullet under the base (usually off center)(causing weight on one side or lack of it on the other) and this will play havoc with accuracy one the bullet leaves the barrel. To insure that temperature is not causing poor fill out I would suggest running a little hotter to start with (you can always cut back on the heat later..if you start to frost) Try 750 degrees to start. If the mold starts to overheat and the sprue starts taking too long to set up, then slow things down or use a small fan across the blocks to help cool. To answer your concluding question/summary about how important is the flow rate...it is very important and there are a few factors that I have outlined that have to be synchronized to get good bullets. It will take some practice, patience and cussing, but you will succeed. Big bullets and very small ones are not the best or easiest to learn with, but it can be done and things will turn out ok. If you can put 1-2% tin into the alloy then the bullets will cast easier and sharper. Keep your pot and alloy clean and fluxed. Good luck. LLS

[upnorthwis]

I have the same Lyman mold. The only flow rate I use is Wide Open. I just count the seconds until it's time to shut'er down.

[220swiftfn]

To control rate of flow on the RCBS, lift handle up less then the full amount, it will take some getting use to, sounds like your melt and esp. your mold is too cold. Preheat mold on hotplate of even on your melter, or prepare to cast many wrinkled bullets before your mold comes up to the right temp. and starts to drop nice bullets.

Um, huh??? There's a nut and bolt on the handle guide that can be adjusted to limit the flow on the Pro-Melt. Agree with the mold temp, with an addition of the mold needing a good scrubbing (possible oil in the cavity).


Dan

[monadnock#5]

You're not rendering wheel weights in your BP pot are you? Fluxing and cleaning is done in a different pot. Only precleaned lead, all ready to go, goes into your BP for making boolits. If you have been rendering in your BP, the orifice at the bottom of the pot is gunked up and it, as well as the whole pot will need to be cleaned before you can pour boolits.

I hope this helps you from casting diseased, nasty looking boolits like I did for a while.

[oneMOA]

Thanks for the replies. After sleeping on it, I believe the problem is my Lyman thermomenter. I was running the lead at about 700 to 750 deg. according to the thermomenter and the mold at about 180 deg. as checked by an infrared thermomenter and kept heated on a hot plate. Yesterday I tried adjusting the flow rate of the furnace spout without much chance, if any in the wrinkles. Today, I'll try increasing the lead temp till I get frosted boolits.

The lead I have on hand is in the form of fishing sinkers up to three lbs each. These were cast by me about 30 years ago from cable lead which would have been pure lead. I cast a number of different size sinkers during that time, from small jig heads to these heavy weights. I remember using some plumbers solder mixed with the cable lead for the small jig heads to make them cast better. I don't remember using any solder in the big weights so I'm calling them pure lead and they are clean.

[h8dirt]

For pure lead. 700 is too cool for the melt and 180 is too cool for the mold. It's been a while since I worked with pure lead, but if I remember right, 800 is closer to right. And, you'll want your mold to be closer to 400. That's been my experience.

[OuchHot!]

I have found myself backing the rate (lever stop) screw out a little as I draw the pot down. The head pressure drops and can be compensated for. But really, get the temperature of mold and alloy set first.

[oneMOA]

So far I've had nothing but trouble and here's where I am at this point. This morning I fired up my RCBS furnace with about 15 lbs of lead in it left from yesterday and cranked the thermostat up to about 800. Fired up the hotplate and I thinking I should be good to go. Once the pot reached temp and the mould was up to about 250 deg I start casting. A few boolits came out good, most were not filled out and the nose had something going on like a roughness, frosty spot with specks occasionally. Fooled around with the flow adjustment a bit and continued to heat the mould. Then I noticed a couple of boolits with larger specks about two or three times the size of a grain of sand, again on the nose of the boolit.

Now, again the lead I'm using is from large fishing sinkers which I cast myself from cable lead and I may have thrown in a stick of bar solder occasionally. My smelting pot was a Plumbers pot which would hold at least 50 lbs or more and still not be full. This was fired with a propane burner. I used a large ladle and fluxed with some commercial flux in stik form, don't know what it was. Moulds were filled from the pot by dipping. These sinkers while over 30 years old, were mostly dark grey and spots of silver remaining, but no loose corrosion or oxidation. I thought this would be clean enough to run in my RCBS furnace.

Since I am getting a foreign substance at the bottom of my furnace pot which I cannot explain, I decided to drain the pot which I have done. I think the best course of action now is to re-smelt all the lead I have on hand and cast in one lb ingots. I have a propane turkey fryer and a Dutch Oven for a pot and try to clean it up.

[OuchHot!]

The only cable lead that I had experience with was pure lead. It does sound like your alloy has a problem. If a couple percent of tin cannot fix it, I would be inclined to resmelt or try to get a quantity of known alloy to get a point of reference.

[country gent]

Clean the mould good and also clean the vent lines with a scribe or exacto knife blade point to insure mold is clean and venting properly. 250 on the mold still sounds on the cool side also. Try sitting the spout right into the sprue plate and filling it with a 3-4 count allowing the head pressure time to work. Lower mould as you drop pots handle. Sometimes tilting the mold a little helps it to fill better also. Experiment a little trying diffrent tings.

[prs]

The history you give for the metal would be pure lead and it WILL NOT frost. A rich lead/tin allow may make you smile. The most recent edition of Lyman's Cast handbook receives some criticism due to Iron Mike providing too much emphasis on your type of shooting, but you should glean a lot there.

prs