Alloy Choices

[burch]

I have a Lyman 429421 mould. I cast some up yesterday for the first time using some 45-70 bullets that have been collecting dust. I have no idea what the alloy mix is but they we`re bought from a local casting co. The weight is pretty good at 240 to 242gr. The dia. is way overboard at .435 on average. My question is what alloy mix is best suited for getting the 245gr. weight and a .429 to .431 dia. bullet. I don`t have sizing equipment since i`m just starting out but have also read that if I use the right alloy mix I won`t have to size anyhow. I figured with a lot of you guys using the 429421 i`d get plenty of good answers here.

Burch

[fredj338]

SOunds like you need to add more straight lead, maybe 3-1, cast a bit hotter, just under 800deg. That should get you closer to spec.

[Leftoverdj]

Lyman moulds commonly run oversized. This is a whole lot better than running undersized. Change alloy can cut a thou or so off the diameter, but it's not going to cut .005 off. Using spray graphite mould release will cut maybe .002 off. It's Lee that tries to cut moulds close enough so no sizing is needed, and they sometimes cut them too small.

Sizing need not be expensive. You can get by with the Lee kit at around $15.

[cajun shooter]

Your 45-70 bullets should have been out of a soft alloy so your mold might be the problem. If you are casting for CAS you don't need a hard bullet. A BHN of 8 will work. When you are casting and trying to do things like drop bullets at the correct size,you need a few more tools. The extra tools that we all have are not there just because and they provide a service that makes casting easier. A hardness tester is one thing that you should have. It's almost as important as the melting pot. That's if you want to know what you have. There will be people who will say I've done without it for 30 years and you can if you want to be blind and never improve your skill. The one sold by Gussy is the #1 and spend the extra bucks for the deluxe model if you ever are going to load precision rifle rounds. Lyman base all the molds on a #2 alloy

[44man]

I have a Lyman 429421 mould. I cast some up yesterday for the first time using some 45-70 bullets that have been collecting dust. I have no idea what the alloy mix is but they we`re bought from a local casting co. The weight is pretty good at 240 to 242gr. The dia. is way overboard at .435 on average. My question is what alloy mix is best suited for getting the 245gr. weight and a .429 to .431 dia. bullet. I don`t have sizing equipment since i`m just starting out but have also read that if I use the right alloy mix I won`t have to size anyhow. I figured with a lot of you guys using the 429421 i`d get plenty of good answers here.

Burch
First, many guys would give up drinking for an oversize mold! :mrgreen: My experience with all molds is they are too small being cut with worn and resharpened cherries. I have never, ever bought a Lyman or RCBS mold that was oversize in 56 years of casting. 95% of the time they are under bore size, the rest are just bore size.
Buy a .430" Lee boolit size die and lap it to size your boolits .432".
Chances are the 45-70 boolits were store bought and made from some super hard alloy. Add some soft lead, they will cast smaller so you size less.
You never said what gun you have but there is never a need for a .429" boolit. If it is a Ruger it will thrive on .432". If a Marlin, it needs .433" to .434".
Someone with a Marlin will want that mold bad! :Fire:

[Lloyd Smale]

if your bullets are comming out that big and that light i would guess your alloy is linotype.