Bullet weight?

D

David Bachelder

New member
I bought a Lyman 4 cavity .358" bullet mold. The mold is supposed to cast 150 grain bullets. I just cast 17 and all are over the 150 grains. The average is 162.66 gr.

The lead was supposedly plumbers lead.

I wanted to cast a few just to get the hang of it (new toy syndrome :rolleyes:).

I didn't expect them to turn out as nice as they did (wish I had our digital camera, but it's resting comfortably in my wifes purse and she is out of town).

No frosting and a few culls (6) , but no big deal.

Lets suppose it was plumbers lead, if I were to add the recommended amount of tin, would the weight go down?

Seems like it would since tin is lighter than lead.

The bullets can be scratched with my thumbnail, I assume this means they are soft (confirm plumbers lead ?).

I have no intention of shooting them.

The tin I purchased is not here yet, so I'll toss these back into the pot.

My concern was that they had possibly sent me the wrong mold.
 
David

The molds are cut to use Lyman #2 alloy ,liter than pure lead.

As long as there consistent & correct size & good base ,shoot em !

Tin does`nt harden lead ,well it does to a point ,more than 2% won`t harden it any further ,ya need some lino type.

I usually run my general handgun bullets around 10.5-11 bhn , rifle needs harder though.

& what`s the 6 digit number on the mold 358???
 
That is heavy for a 358477 ,but don`t sweat it my 2 holer drops 155 grs. with my alloy. Like I said, if the deminsions are good shoot em !!
 
Yup, GP pretty much covered it, but I'll reinforce. Weight is calculated on a specific alloy for the mold. Unless you buy certified metals and cook up your alloy perfectly, it's going to run up or down. The key is NOT to hit the mold's estimated weight--you want to drop a CONSISTENT weight for the alloy you develop and use. My 160gr mold for my AK and Mosin actually finishes at 173gr with a GC. My alloy runs frighteningly well in both rifles, so monkeying with it to get the weight where it was advertised would be pointless.

Work your alloy to what functions best in your firearm and load accordingly--then just keep it consistent.
 
Shoot em.
If they are, indeed, pure lead, you will likely want to keep the velocities down to around 800-900fps, but they should work fine.

To add more... If you cast those bullets out of pure linotype, they would probably weigh about 150gr or possibly even less.
Alloy makes a difference... as does casting temp.
 
If you want to add some tin you can use some 50/50 soder. If you want a bit of antimony in it use some plumber's silver 95/5 solder. 95%tin, and 5% antimony. I usualy add about a quarter pound to 20 pounds of wheel weights when casting for my .41 mag. I can run them pretty darn hot without a leading problem.
 
I ordered some tin and some superhard 30:70 Antimony/Lead from Roto Metals. Mixed up some Lyman #2.
90% Lead
5% tin
5% Antimony

Now my average bullet weight is at 150.62, huge difference. Now the mold is throwing bullets in the right neighborhood.

Not bad for a Rookie.
 
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If you want better boolits, I have learned to keep the casting temp stable. Do not go adding sprues back into the pot willy nilly. This will drop your pot temp and when that happens your boolit weights will be less uniform.

Maintaining uniform pot temp while casting is essential. Also keep in mind that as the pot empties, your temp will increase. Keeping this in mind and developing a routine which accommodates for it will propel your homemade boolits from cheaper than jacketed, to better than jacketed.

How to tell if you're doing it right? Weigh the boolits. The more uniform they are, the better you're doing.
 
Amen to what Ed is saying there on the pot temp.

Here is one batch I poured up for my 454 of the Lee 300gr RF GC, as you can see, they started off heavy, on the bottom, then I got everything up to temp properly in the middle, and as I got towards the end of the alloy it was getting hotter and so was the mold, but I wanted to finish up. As such I threw the top three rows a bit lighter, plus some which simply didn't make the cut and went back in the pot.
P7110234.jpg


Another thing about when your mold gets hot is the cavity also gets smaller, which in turn will toss lighter bullets as is evident in the pic. The opposite is also true as well. With the 6 cavity mold I poured these with, I installed one of the following temp probes,
Digital Mold Thermometer

To be honest when I first got it I thought, "man this is pretty darned cheesy", but I figured I would at least wring it out, and found that it is actually very well suited to the purpose. I keep the mold temp in the 310 to 340 degree range, and the alloy around 650 - 675, and I can just about hit the 306-308 grain range with them all. Also as you have already learned your alloy can and does also make a difference in the weight your mold will throw as well.

Keep up the good work, sounds like you got it going your way.
 
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