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riflecountry
02-22-2015, 12:25 PM
I was shooting for 20/1, had a pretty clean mix, but added some plumbers lead and a corresponding amount of tin. Boolits are sometimes dirty looking, kind of frosted in one spot(consistent location on the boolit). Fluxed this stuff 10 times at least to try to cure the problem, to no avail.131674The cooled pot afterwards has these huge voids and weird spots in it. is this some kind of odd metal in the mix that causes this, or does it look normal?

JSnover
02-22-2015, 12:40 PM
Maybe a cold spot or blemish/contaminant on your mold. Aside from the frost, how are they dropping (size, weight, surface finish)?

country gent
02-22-2015, 12:44 PM
It dosnt look to far off for cooled lead. Telling if ratio is correct or impurities by eye is hard to do. What are you fluxing with? Sawdust/wood chips. beeswax, or something else. The pot shows a few flecs of dross on the surface is why Im asking. WAs the plumbers lead new or old and corroded some? The frosted appearence may be temp related or a rough spot in the mould. What temp are you casting at? To hot will make it hard to maintain the alloy and cause frosting. With 20-1 I shoot for 700*-750* on the pot and a cadence that keeps mould hot. Preheat the moulds and bring alloy up to temp, lightly lube sprue pivot and start casting at a moderate pace pouring a large sprue and letting it cool fully before cutting.

riflecountry
02-22-2015, 01:11 PM
They drop from the mold nicely, consistent weight, and surface finish is great except for one side, where all the blemishes seem to occur. Some of the bullets, right after I flux and scrape off the dross, don't have the blemish at all, they are perfect, which is what led me to believe it might be the mix. I am fluxing with a small pine(?) wooden stick, and have also tried bullet lube.(white lightning). It could be the temp is too high, I run at 770 or so. Following the rest of it very closely. Thanks!

riflecountry
02-22-2015, 01:29 PM
Here is a pic of good one vs bad.131686

country gent
02-22-2015, 01:49 PM
Try cleaning the mould blocks and vent lines really good. Scrub blocks with dish soap and tooth brush the lightly pull a scribe or awl point thru the vent lines in the blocks and re clean with dish soap hot water and tooth brush.

powderburnerr
02-22-2015, 02:13 PM
are you ladle pouring with the ladle spout married to the spout?? and is the ladle full. ?

riflecountry
02-22-2015, 03:53 PM
I marry the ladle and mold, slowly rotate 90 degrees to level, about 3 seconds to get to level. Hold the ladle in position for about 3 seconds, then pour the remainder of the ladle, (which started full) into a sprue on top. Usually take about 6 to 8 seconds to harden, then I count to 5 before cutting the sprue and opening the mold. Just tried running a little cooler, 720 degrees, seemed to help. But I get random results. One bullet is nearly perfect, the next consecutive bullet has the weird stuff pictured above, and worse! Not making much sense to me.

riflecountry
02-22-2015, 03:57 PM
This is a brand new mold, is there a break-in period before they start turning out consistent results? Maybe some time required to burn out all the oils and stuff in the pores of the mold? I seem to recall having similar issues with the Paul Jones mold at first, which works beautifully now. But this mold and the PJ were both sent with sample bullets cast from the molds which are perfect.

kokomokid
02-22-2015, 04:13 PM
Let the pot cool and dump the alloy chunk and brush the ash off the bottom of it and out of the pot.

Chill Wills
02-22-2015, 06:00 PM
I think I would bet the fix country gent outlined has a good chance of fixing your problem.

Clean the mold real well with soap and water. BTW-is this a Brooks mold?
I bet you have a good mold and alloy. You just need to get it clean. No break in with these molds - they will cast.
My bet is -Some how some oil or grease like stuff got in there.

Just for good measure - Flux your pot one more time but with some sawdust- just about a 1/4 measuring cup full of sawdust (20lb pot) let it burn down (5min) and stir well and remove junk.

I really think the mold is the problem tho....
I have had this problem myself countless times over the years. Even after using mold for thousands of bullets over scores of casting sessions and then bam! - it stops casting well.

The fix is to stop casting.
Disassemble, ...which is not hard, do it.
Clean-Clean-Clean.
Dry it with a paper towel.
Hit it with some carb cleaner if you have some.
Let that dry.
Reassemble. KEEP the top plate loose! Adjust it so it will swing free -but just free. Adjust to that point between loose and wont swing. It works.

Now;
Attach to handles and put the mold on the edge of the pot with your ladle and cover (the Pot, Ladle and Mold) with a small piece of tinfoil.

Start the pot if it was off - wait 1/2 to 45 minutes. Skim the top and cast bullets.
You know the Paul Jones way to cast so you are all set. It will work.

riflecountry
02-22-2015, 06:46 PM
It is a Brooks. 440 gr. 40 cal. It came with a sample bullet, and one in the cavity, which I didn't remove until just before casting. It was well packaged, and the sample must've been cast shortly before I started casting with it myself, so I can't see how any oil or grease would have gotten in there. I wish I would have started with my old alloy, then I would know, but it was getting low so I added the additional lead. It was an old piece of lead pipe, and yes it was pretty dirty, but I haven't had problems with it in the past by fluxing and cleaning really well. After the initial problems , I scrubbed the mold with hot soapy water and a toothbrush, still the same. this mold casts nice, round boolits, by the way, very pleased with it so far, with the good boolits anyway! I am starting to think it is the alloy more and more. I will pull out the block and scrub the pan real well, as suggested above, and try to get everything super clean.

Chill Wills
02-22-2015, 07:22 PM
I agree with you about the mold being ready to go as received from Steve Brooks. I have no answer for that.
I hear you about your old alloy too.

Do you have a different alloy to try if the Sawdust cleaned alloy you have now is still a suspect?

When you say "pull out the block" - do you mean mold block or empty the casting pot?

13Echo
02-22-2015, 07:47 PM
Clean, dry, preheat on a hotplate and smoke the mold cavity. On molds I have that give wrinkled bullets like that smoking usually fixes the problem

Chill Wills
02-22-2015, 08:05 PM
Yeah 13Echo. I agree. I would, after cleaning, add a coat of Rapine micro graphite, BUT really, it should not be needed. That Brooks mold should be fine if it is clean. Even rubbing alcohol on a q-tip would do it most times.
Brooks molds are first rate!

I bet riflecountry gets it going, just needs to keep at it.

riflecountry
02-22-2015, 08:05 PM
I meant empty the casting pot, sorry.131750131751Here are the 2 consecutive bullets I referred to above. 720 deg, using the pour method above, tried to do everything exactly the same. This doesnt look like a typical wrinkle, I have seen that before. Getting tired of fighting this, so this coming week I will try the sawdust flux, as well as emtying the casting pot and cleaning, scrub the mold again, and if that doesnt work, smoke the mold, and maybe start over with a known clean alloy. Thanks for all the help, guys!

powderburnerr
02-22-2015, 09:37 PM
that looks like oxidation on the side of the bullet , either from a shallow ladle or a contaminated spout , you can minimize it by keeping the ladle on the bottom of the pot , and running some alloy out as you draw it to the top,and you say it disappears for a couple when you clean it up with your stick for a couple..
If the ladle sets on top of the pot it will get covered with oxidation and will do that to the bullet.

riflecountry
02-23-2015, 08:25 AM
that looks like oxidation on the side of the bullet , either from a shallow ladle or a contaminated spout , you can minimize it by keeping the ladle on the bottom of the pot , and running some alloy out as you draw it to the top,and you say it disappears for a couple when you clean it up with your stick for a couple..
If the ladle sets on top of the pot it will get covered with oxidation and will do that to the bullet.

This sounds like it could be the problem. I will do some experimenting!

13Echo
02-23-2015, 08:41 AM
Oops. Looking closer at the pictures I agree that is a problem with dross in the metal, not wrinkles. Metal needs cleaning or casting technique needs work. I always get a ladle full and pour out the first bit before hooking it up to the mould. That gets rid of any dross that might be in the spout.

Jerry Liles

kokomokid
02-23-2015, 11:07 AM
Have you tried turning the mould to a different clock setting to fill ( so first alloy in is at different location ) and see if the area in question follows. I have got some really crappy stuff in heavy lead pipe, maybe zinc or whatever.

Knarley
02-23-2015, 06:53 PM
Not to hijack this thread, is post # 8 a description of the Paul Jones method?
Knarley

Wayne Smith
02-23-2015, 07:10 PM
Not to hijack this thread, is post # 8 a description of the Paul Jones method?
Knarley

No, that is a description of pressure pouring with a ladle. Been going on for a long time, Lyman matched the angle of their sprue holes with the angle of the outside of their ladle.

Chill Wills
02-26-2015, 11:20 AM
Riflecountry, Have you shot any of the bullets that you show as surface blemished? If you can rub your finger on the bullets and just barely detect the oxidation, weight them, assuming they are with in weight, they likely will shoot well.

Now, I am NOT saying you should give up on making perfect bullets. Just saying that many casting runs I have may show some of this too but the bullets shoot well. Very well in fact! Often it is just cosmetic imperfection. Experience will let you know which and what to worry about and what is OK.

I thought of this thread because yesterday I cast my bullets for the four day Creedmoor match that will be held in Arizona in two weeks. There isn't a more demanding test of these bullets. Most of the run of 16-1 Lead- Tin bullets I made did not look as good as yours. However, I will compete with them. They are fine and first rate and will shoot well. Reading and shooting in the conditions during the match will decide my fate - the bullets will perform fine.

I cast a batch of 50-50 WW-Pb +1% Tin added also. Those bullets look better than the run of 16-1. I expect both alloys to shoot just fine.

Let me know how your bullets turn out on your next casting session.

Michael Rix

riflecountry
02-26-2015, 10:58 PM
Michael,
I have shot a few, around 20 or so, looking for a load for my 40-82, 14.5. twist green mountain. They shot extremely well in one of the loads! I was a little worried, however that these spots might be some strange material and have some hardness to them that could scratch the bore. From your posts and others, I think I won't worry about it. Just yesterday, I tried casting some more, after cleaning the ladle, pot, mold, and trying to skim as much dross out of the batch as possible. My results may have been somewhat better, but still getting the random bullets with those oxidized spots. I am gonna try a batch of fresh alloy tomorrow and see what happens.
I have shot silhouette with you in Whitewater a few times, just shot there a couple weekends ago. I was asking about whether you shot there any more, and wanted to get in touch to see if I can get some more of your lube. Thanks for the help!
Greg Fisher

Chill Wills
02-27-2015, 08:32 PM
Hey Greg, Give me a PM on the lube and if I have what you need on hand I will try to get it out before I go to the Arizona match.

I miss living over on the western slope. I never thought I would be where I am now but life takes some twists and turns. We only have a few more years here and then we'll be free to get back there again! Do you see Bernie often? I should give him a call. That was a fun bunch to shoot with; I miss it!
You take care...

riflecountry
02-28-2015, 09:00 AM
Yep, life can sure take some unexpected turns. Bernie was there a couple weeks ago. And yes, they are a great group of guys to shoot with! PM sent.