My first bullets are ok, but not great.

[njc110381]

Hey guys. I just went out and cast my first batch of .457-405 bullets. I messed up a few, and none are perfect. I'm thinking I should talk you through what I did and see if there's an obvious answer that I'm missing? The problem is that one side of the bullet is pitted. It looks usable, but it's not ideal.

First off I fluxed my lead and mixed it with 10% pewter, then fluxed a few more times until the mix looked clean. Whilst the Lee pot warmed up I cleaned out my mold with panel wipe and cotton buds, then sooted it up with a few matches and lubed it lightly on all the parts that need it. I pre heated it in the lead for around 30 seconds, which made it a bit hot I think because the bullets didn't solidify for around a minute. I let it cool a little much and made a few that didn't fill out well (hey, I'm new - I was expecting to mess the first ones up!). After a while I got it running good. Nice shiny bullets mostly, but one side of both bullets is pitting every time.

Any idea what's causing this? I'm wondering if I got a bit of wax in there when I lubed the pins - would that do it? I don't think I did, but that doesn't mean it didn't happen. I can't get a decent picture on my phone and the camera is packed up because I'm about to move house unfortunately. Pitting is the best description I can think of. It's deeper and more coarse than frosting, but the fill out is good and they're perfect on one side! I'm confused!:roll:

[Yodogsandman]

Cut yourself some slack, it's tough to get those big ol' bullets to fill out and drop out pretty! The key is to fill the mold as fast as possible, maybe with a ladle.

You don't say exactly how you fluxed but, you didn't mention reducing either. Flux 2-3 times with a dry organic like sawdust, skim and reduce once with wax (or oil) and skim again. Stir and scrape the pot sides while fluxing and reducing. You can touch the smoke off with a lit match to reduce the poisonous gasses. This will clean your alloy and reduce any oxidized tin back into your alloy.

10 % tin (or pewter) is overkill! One or two percent is enough to get the sharp edges and corners to fill out using your lead.

Those pits on one side are inclusions. Your alloy and mold are too hot. Try getting the alloy heated so that when you pour a cast, it takes 3 seconds to flash harden on the sprue plate and then wait till 6-7 seconds to open it without any lead smearing.

[gray wolf]

I think you can also skip the wooden Match, not needed.

Stop wasting the tin, 2 % is all you need. What was your alloy ?

What did you lube the mold with and how careful were you not to get it in the cavities ?

How are you judging your lead pot temp. ?

[John Boy]

which made it a bit hot I think because the bullets didn't solidify for around a minute.
The pot melt is WAY TO HOT! You had best buy a thermometer!
http://www.teltru.com/p-272-big-green-egg-primo-komodo-grill-dome-or-other-kamado-style-replacement-thermometer-lt225r-5-inch-stem-2001000-degrees-f.aspx
Then after fluxing - cleaning the mold - heating the mold ... the temperature you want to maintain the pot is after a 5 second pour ... the sprue puddle frosts in 5 seconds!

[pjames32]

Clean the mold again with dish soap, hot water and a toothbrush. Dry with acetone or brake cleaner. Be cautious when you lube the pins.
Plus 1 to the above advise on mold and alloy temp and too much tin.
A big 45 boolit is a tough one to start with. Keep casting!
PJ

[njc110381]

Thanks guys. I'll clean the mold again and have another go.

When I finally got them working to a usable level they were setting in around five seconds. It was just the first one that took that long to set because I left the mold in the lead for too long. I let it stand for a while to cool, then after that was dabbing the sprue plate on a damp cloth every forth cast, which seemed to give the best result.

Temperature wise I'm using a Lee pot with the adjustable thermostat. I started it off on full, probably for too long. I then set it to 3 which caused it to set on the pot sides a little and the nozzle blocked (apparently they don't work so well with 240 volts) so I tried 7 which frosted them, so finished up on 5 - I think 4 may be better next time.

Alloy is roofing lead with 10% pewter. It's soft but I hope it will be ok for light loads. I'm planning to use 10-12gr of Unique?

I'm glad these big bullets aren't regarded as easy. That means I'm doing ok to get them as good as they are!

I nearly forgot to answer the flux question. I've used pea sized balls of candle wax and have scraped the sides of the pot a number of times. Maybe 5? Not used saw dust though. Is the wax not good enough, or a different stage of the process?

Thanks again for your help. It's very much appreciated.

[44man]

It is a hot spot on one side. When all is right even very large boolits are no problem. Just need better temp control.

[runfiverun]

one area off like that is severe frosting, caused by the alloy hitting the same spot in the mold time after time causing it to heat up more than the rest of the mold.
your just going through a learning curve of how things need to be.
6-7 on the pot after a 20 minute warm-up should be closish, the important thing is mold temp you regulate that through pours per minute.

[Echo]

My guess would add a possible venting problem. I've seen that happen, and was cured by 'breaking' the upper edges of the mold blocks with a stone, or very fine file. How does the sprue plate fit? Tight, or loosy-goosey? Should be fairly loose, but not loosey-goosey.

[pretzelxx]

I cast a week before I got anything remotely use able. I didn't use a thermometer tho. Now that I do, with a hot plate for molds... It helps!

[njc110381]

The sprue plate fit seems nice. It's smooth to open and snug, but it's not tight.

Regarding the hot spot on the mold, how do I cure that? dump the bullets out a bit more slowly to give it a chance to disperse? I'm pouring straight down into the mold so would be surprised if it's hitting one side more than the other?

One thing's for sure, these big bullets are using a lot of lead! I might buy myself a .30-30 at some point...

[Yodogsandman]

Once you dump the boolit, just wait (with mold open) for about 10-15 seconds before refilling the cavity. Less time if you blow on it or use a fan.

[njc110381]

Ah, that could be it. I've been shutting it again as quickly as possible because I didn't want to over cool it! I'll try slowing down a little. Thanks

[Markbo]

I cast a week before I got anything remotely use able. I didn't use a thermometer tho. Now that I do, with a hot plate for molds... It helps!

Exactly what i was going to say. And while the steps are all pretty straightforward, there is a learning curve. Keeping everything just right throughout a session comes only with practice. The good news is if you dont like one drop or one pile throw 'em back in the pot and keep going. :D

[robg]

sometimes its helps to let the lead swirl into the mold instead of straight in the hole ,one of my molds needs this technique or i get the same problems.if the sprue takes more than a min to harden pot to hot just turn it down a little till it works right. my lee pot seems to work best at 600 on dial

[Yodogsandman]

Be aware that each mold is an individual and will need different ways to get the best bullets. Some will like a faster or slower cadence, some will want a faster or slower fill, some will need a big sprue puddle where other won't....just be flexible and try different stuff when you're faced with a challenge.

A thermometer is nice to have, I guess. I still don't own one for casting, though. I've cast tens of thousands without one. Having a way to measure and control the heat will enhance your casting and reduce the learning curve. They do help.

In the past year, I've added a PID unit to my pot, a hot plate and mold oven with a bi-metal thermometer, a hanging oven thermometer in my convection toaster oven for heat treating and a reptile heater control to my lubrisizer.

[njc110381]

The good news is if you dont like one drop or one pile throw 'em back in the pot and keep going. :D

Oh I did plenty of that. probably 30% of what I made went back in!

I figured straight in was the best way to pour it, but will try other angles now I know I should. It will work out in the end. My biggest worry is that my lead won't be hard enough to shoot well. Then I'll have to melt everything I've made (about 120) and start again. I don't want to run it fast but it seems that pure lead is only ever used in muzzle loaders?

[country gent]

Several things to do here to help you get to those pretty clean sharp bullets. First off buy a spiral note book and keep notes of what youve tried and the results. This will allow you to look up a given mould and see what alloy temps and technique worked and start out right. A thermometer is a big help in repeating results and tracking issues. The numbers on a lee pot are subjective and ambient temp affects them alot. A thermometer in the pot allows temp to be duplicated. I wouldnt smoke the mould as its another variable thats hard to control, to heavy a coating and you get smaller bullets to light and bigger. Also as a session goes longer it thins from use. Lube alighnment pins hinge points lightly with a high temp lube 2 cycle oil works well applied sparinrly with a q-tip. A small touch on the tip and wait a few moments for it to disperse thru the cotton. It dosnt take alot. Vent the top of the blocks may help but be very carefull as to much may cause fins. There are several casting techniques to try pressure pour, drop or free flow, swirl flow. Pressure pouring you place the nozzle of the pot or ladle tightly into the sprue hole and pour holding for a few seconds after full. Try mould straight and at a slight angle here. Free flow is holding mould about 1/2" or so below nozzle and pour in mould full forming a bigger sprue. Swirl flow ( my term or description here) is pouring down side of sprue plate causing lead to swirl in mould and forming a larger sprue. Wait for sprue to frost then another 5-7 seconds ( remember blopcks are insulating bullet and its at the full temp also) cut sprue and drop bullet out. Close up blocks, sitting on a small piece of angle iron or steel rail helps pre alighn blocks slowing wear on pins. Close sprue plate up carefully. I then give the blocks 2-3 light taps on handle at the moulds junction to insure they are fully closed and seated. These are very light taps. I use a 8 ounce plastic cap hammer for a mould mallet also. The big thing is do everything the same way each cast and document what youve done each time.

[Motor]

Big boolits are tough to make pretty especially with a Lee aluminum mould. The 440gr .501 is a perfect example. I think this mould would have been much better if it was a single cavity. I added material to the exterior giving it more bulk and it helps but keeping it at a good casting temperature is still not easy and frosting on the sides of the boolits that are closest to each other (center of the mould) is still very common.

The boolits are accurate though and that's what really matters in the end.

OP: Just keep at it. But pay attention so that when you find that sweet spot you'll know why and be able to repeat it. After fighting the 500's then switching to something like 30cal rifle boolits you realize its not all you.:)

Motor

[DeputyDog25]

Clean the mold again with dish soap, hot water and a toothbrush. Dry with acetone or brake cleaner. Be cautious when you lube the pins.
Plus 1 to the above advise on mold and alloy temp and too much tin.
A big 45 boolit is a tough one to start with. Keep casting!
PJ
Hey Paul, you forgot to mention that he needs a PID from a certain individual to help him out with temperature...[smilie=1:

[njc110381]

Yet more info to try. Thanks guys - I'll have it sorted in no time with all the help you're giving me!

[dondiego]

Oh I did plenty of that. probably 30% of what I made went back in!

I figured straight in was the best way to pour it, but will try other angles now I know I should. It will work out in the end. My biggest worry is that my lead won't be hard enough to shoot well. Then I'll have to melt everything I've made (about 120) and start again. I don't want to run it fast but it seems that pure lead is only ever used in muzzle loaders?

Your alloy will be fine with 10-12 grans of unique. Doesn't need to be too hard.

[njc110381]

That's great to hear. I'll load some up and range test them. If they do lead the barrel is it ok to keep lobbing them down range anyway or will they need to be pulled? I'm thinking I'll make 50 to start with.

[dondiego]

If they lead the barrel, they are most likely too small in diameter. If they do lead, you can keep shooting but your accuracy will suffer. I have had real good luck with all sorts of alloys in 45-70 if the boolit is large enough.

[grouch]

I wouldn't worry about the bullets being too soft. I use 18 or 20:1 lead and tin and get very good accuracy from my 45-70. Others use alloys down to 30:1.
Grouch