Moulded bullets came out undersized.

[Diz9000]

Hi all.

Well my tale goes like this. A fellow shooter has been teaching me the art of casting our own balls & bullets. He's been casting for many years so I was happy when he told me he would show me the ropes .

Anyway, to add to our choice of cast bullets I ordered the Lee prescision .54 REAL mould. I left the mould with him when I went out to pick up some lead from the local scrap metal merchant. I got a nice bag of roofing lead off cuts that had just been bought in by a roofer.

So I return to the casting shed ( his old garage ) and he has made himself a couple 100 whilst I was away, this all but emptied his helming pot. We then fed in my lead and he continued to mould around 300 for me.

Now we went to the range this afternoon to try out the new REAL bullets, he has a .54 Thompson Center Arms Renegage and I have the .54 TCA Hawken. My first 3 shots took out the 10 at 35yds, now his first 3 shots missed the target completely, he says the bullets just drop down into the barrel where are mine need to be hammered in with a bullet starter.

I tried one if his bullets in my gun and yes it dropped straight in, and my bullet in his gun needed hammering in.

Now the only difference I can see between the bullets he has and mine , is a different lead was used.

Looking at the actual bullets, mine are nice a crisp with sharp edges , where as his are obviously slightly smaller and the edges are more rounded and not as crisp/sharp looking.

Is the issue with his lead ? Or could something else be causing his shrinkage ?

Cheers

Dean.

 

[cynthialee]

lead purity

 

[mooman76]

Sounds like the mould wasn't running hot enough for good fill out. This is fairly common with the Lee REAL moulds. They like to run hot. Another thing he could do is add a slight amount of tin to his melt. Just a slight amount of tin will help with fill out without adding any significant hardness to the lead.

 

[Dwight Rutherford]

I don't see any mention of a patch being used. If not, why? If yes, was the same patch used for both guns?

 

[Grenadier1758]

No patch is needed for REAL (Rifling Engraved At Loading) conical bullets. The bullet has driving bands that are of larger diameter than the land to land measure.

The question I have is were the bores measured for diameter and were the REAL bullets measured for diameter?

Different alloys of lead will have more shrinkage in the mold than pure lead. I am leaning toward a difference in the composition of the lead (?) in the first batch.

 

[mooman76]

I also should mention and over powder wad helps REALs shoot better. You do still need to work out the casting problem though.

 

[Dwight Rutherford]

Senior moment on my part! Missed the REAL bullets.

 

[Diz9000]

Sounds like the mould wasn't running hot enough for good fill out. This is fairly common with the Lee REAL moulds. They like to run hot. Another thing he could do is add a slight amount of tin to his melt. Just a slight amount of tin will help with fill out without adding any significant hardness to the lead.

That's good to know, I'll pass on the information to my casting buddy :thumbsup:
I was leaning towards a different mix of lead, but it could be combination of the two issues.

Now his REALs were the first 100 out of the mould, so the mould would if been cooler and his lead was reclaimed roofing lead , where as mine was off cuts off unused roofing lead.

We will have to keep an eye on the casting process .

For now , he is going to stick with a Maxi-balls, but I prefer the REALs and patched ball myself :grin:

Thanks again for all the sage advice guys.

 

[mooman76]

Different lead alloys will make some difference but in the case of the REALs, not much. Pure or near lead will come out about .002 smaller than alloy give at take a little. The REALs are designed to come out .017 over bore size so a different alloy should still not slide down the bore plus the REL is designed with pure lead in mind. Also you did state yours came out crisp with good edges which is the way it should come out, not rounded like his. Pure or near lead pours better at higher temperature than alloyed lead.

 

[Don Steele]

The critical variable that you and your friend weren't controlling is temperature. As already pointed out, from the description you provide it sounds like your "crisp" bullets were cast from a hot mold with hot metal, his more rounded ones were the result of either metal that wasn't hot enough, or a mold that was likewise not fully up to temperature.

 

[ZUG]

The critical variable that you and your friend weren't controlling is temperature. As already pointed out, from the description you provide it sounds like your "crisp" bullets were cast from a hot mold with hot metal, his more rounded ones were the result of either metal that wasn't hot enough, or a mold that was likewise not fully up to temperature.

To the OP - This is most likely your answer. Up the temp of your lead - cast 25 bullets and throw them into a can for remelt - don't throw them back into the pot right now this will cool down the pot. Cast another 25 and see how they look if OK keep casting.

 

[Diz9000]

I will pass on the advice thank you, whether he follows it remains to be seen lol. But I know I will when I cast my next bullets.
I will also sort through the ones he made for me, to make sure they are all nice and crisp looking :grin: Having fired one of the less defined bullets from my gun and missing a 12inch target at 35yds, just goes to show how crucial getting these cast right.

Now if only he can be convinced on the benefits of lubing his cast bullets...... but that's another story lol

 

[Maven]

"Now the only difference I can see between the bullets he has and mine is a different 'lead' was used."

That is a plausible explanation. Also, the bore dimensions of the 2 different bbl's. have to be considered as well even though they're both marked T/C (different production runs and/or manufacturers). Try casting with the same "lead" he used and/or try some of the REAL's your friend cast with his alloy in your rifle to see if things improve.

Btw, I had a similar problem with a too-small casting REAL and got a better fit, and better accuracy, by paper patching it.

 

[Diz9000]

I tried some of his less defined bullets in my rifle and they dropped straight in , not even attempting to engage the rifling and hence when shot missed the 12 inch target at 35 yds.

He stays convinced that his rifle just doesn't like REAL bullets , even when the evidence of shooting a few of my more defined bullets nicely took out the 10 ( from his rifle ).

Taking what everyone has said , I'm thinking it's a combination of different lead / lead alloy and the heat of the mould. I have found other mentions of REAL bullets preferring a 'hotter' mould and have also been told , that another caster tends to discard his first couple dozen REALs to the pot for remelting later on.

 

[Rifleman1776]

a different lead was used.

Answered yer own question.
Also, even though same manufacturer, barrels can vary in bore size, rifling depth, etc.

 

[mooman76]

I preheat my moulds so I have few if any to discard. If he refuses to be convinced with his own eyes then he will miss out on allot and maybe that's why his casting experience is limited. Every mould casts different and adjustments need to be made accordingly. Some mould drop good bullets easy and some are picky and need more heat or other adjustments to drop good bullets.

 

[Billnpatti]

From your description of the shape of his bullets, there could be two things afoot. The most likely is that he is not allowing his mold to get up to temperature. This can, and usually does, cause bullets not to fill out in the mold. This results in undersized and misshapen bullets that usually have rounded corners where they should be square. This is easily resolved by allowing a corner of the mold to heat up in the molten lead for a few minutes before starting to cast bullets. Also, in order to keep the mold at the correct temperature, the rate of casting must be kept up so that the mold isn't allowed to cool between bullets.

Another possible problem can be found in the lead purity. Pure lead will cast the size of bullet or ball that is printed on the side of the mold. All molds are made for casting pure lead. If the lead is not pure, but rather an alloy of some kind, the thermal expansion coefficient will be different from that of pure lead resulting in balls or bullets that differ in size from the size printed on the mold.

As I see it, the solution is to make sure that he is casting pure lead and that he is allowing the mold to heat up sufficiently.

 

[mooman76]

I think it was more of the lead wasn't hot enough. If he cast 300 bullets and the mould wasn't hot enough, either he was moving slower than molasses or the lead wasn't hot enough to begin with. As mentioned though, he has to keep his speed up to get the mould hot enough and keep it there, especially with Lee aluminum molds. They heat up quick but on the down side, they cool off quick too. It is important not to fool with the bullets too much while casting. While you are fooling around with the bullets trying to see if they come out all right or not the mould is cooling. I take a quick glance while casting but because I have the years of experience and speed to go with it I can do it fast enough to not slow myself down.

I also add lead to the pot as I go with small ingots. Allot of people have large ingots which will cool the pot down enough to slow or stop your operation.

 

[Billnpatti]

Oh, one other thing I forgot to mention is to be sure to "smoke" your mold cavity(s) before you start casting. This will do two things, it will help the cast ball or bullet to drop free from the mold and it will help the mold to fill out. Smoking just means to coat the inside of your mold with a light coating of soot. You can use a wooden match(s), a candle, a kerosene lamp or a butane lighter. I prefer the long butane lighters that are intended for lighting candles.

Also, be sure to apply a tiny bit of pure bees wax to the sprue plate pivot pin when the mold is hot. This will lubricate the hinge pin and help keep the sprue plate from galling. There may be other products out there that will work but I, personally, do not know of any. All other lubricants, of which I am aware, will not withstand the heat and will form gummy products on your mold and sprue plate. Bees wax works great and is cheap. If anyone out there knows of another product that will work as well or better than bees wax, please share your knowledge with us.

 

[mooman76]

2 cycle oil. It is made to withstand heat. I use it all the time and apply sparingly with a Q-tip.