Lyman 458132

[Dragoon 45]

Last week I cast about 150 Lyman 458132 Postells. When I went back to weigh them, I got a little surprise. Using 25-1 alloy they cast out at 523 grains +/-. If memory serves me correctly they should be about 535 grains. Last time I used this mold, I used 20-1 alloy and most of the bullets weighed around 540 grains.

I used certified alloy. All bullets were ladle cast. The majority weighed at 523 grains and anything that was more than a grain off went back to the cull bin. I put a caliper on them and got .459 as cast. The bullets were examined for obvious faults as not completely filled out or wrinkles, etc.

Just trying to figure out if I did something wrong. I expected them to weigh more. Have not shot any of them yet.

Thanks.

[Southern Son]

Do you have a hardness tester? If you have one of the old ones, you could see how it measures up against one of the new ones with a hardness tester. It may be certified alloy, but everyone makes mistakes. I have that same mould and 20/1 normally weighed in with 530-535grains, depending on the batch of alloy.

[44 WCF]

I just sold that same mould and never cast with it but had purchased bullets that weighed right at 543 gr with the casters 25:1 alloy. My guess was the foundry mis stamped alloy, something that with today's price of tin, they would regret.

[Dragoon 45]

I don't have access to a hardness tester right now. I loaned mine to a friend who is out of states till the end of the week.


Do you have a hardness tester? If you have one of the old ones, you could see how it measures up against one of the new ones with a hardness tester. It may be certified alloy, but everyone makes mistakes. I have that same mould and 20/1 normally weighed in with 530-535grains, depending on the batch of alloy.