Lead Bullet Weight Variance

[MI2600]

I sorted out some lead heel .38 Long Colt bullets from a vendor. They were supposed to be 150 gr. But weighing a few of them I found they weighed between 154 gr and 159 gr. Is this a normal occurence?

My only loading data for the .38 LC is for 150 gr. Are these usable using data for the 150 gr and maybe reducing the charge .1-.2 gr?

 

[oldpapps]

The more lead, the less of the lighter materials. More lead is softer and weighs more.

Unless you are pushing in the upper end of the pressure bracket, the softer/heaver bullets would be of little concern to me. But then... I always drop back a bit and adjust for any component changes.

It is up to you to determine if your loads will need to be adjusted for the minor (% wise) increase in weight and softness.

 

[MI2600]

The bullets are for my pre-1901 Colt DA 38s. Not the strongest gun ever made, so I load toward the low end.

 

[41 Mag]

The weight can vary quite a bit as you see, usually it is from the casting temp of the alloy and/or the mold temp.

This is one of the reasons why I always recommend new casters to pick up a thermometer. While you might not need one to pour up a big ol batch of bullets, if you want any consistency to them you need to keep everything running at a constant temp.

When you first start off usually the pot is full and the mold is cool. As you pour the mold heats up, and the pot level gets lower. As it drops it also heats the alloy up which in return will change the weight of the bullets as well as the size of them as the mold heats up as well.

Here area couple of links to other discussions on this,
Bullet WEight Variations

Analysis of cast boolit weight variences

Not to worry though, I doubt seriously that loading lighter loads for your handgun that you will notice much if any difference from one shot to the next.

 

[MI2600]

Thanks. I actually bought these from a vendor (a grouchy old guy) who was recommended.

These heel bullets can be a "treat" to load even without weight inconsistencies.