Swaging metal powder cores...

[Ammosmith]

When swaging metal powder cores...how do you keep it from crumbling when the bullet is going through the point forming operation? Is there a binder used?

[CPTCUFFS]

I'm just guessing but maybe sintering the bullet in a furnace will keep it from crumbling.

[Jim_Fleming]

Somewhere on here, there's a recent posting/thread about using powdered lead dust as a core, I participated in it. I distinctly asked how the bullet maker kept the lead dust from falling out? Simple, he wrote, he just tamped it into the jacket with a .190" steel rod.

AFAIK, about other materials, I'm pretty sure that sintering is the way it's done, just not nearly as much pressure to keep the core frangible.

If a soft binder such as swage lube or paraffin wax were used, you know already, that'd just make a squished out mess...

[sagacious]

Ammosmith,
Your question is to too general to answer with any specificity. Different metal powders need to be handled differently.

Can you narrow down your question?

[MIBULLETS]

Ammosmith, I have used some of Corbins powdered copper and it does have a binder. Lithium Stearate. I still have some crumbling in the point forming operation, but not too bad. I have used a very small piece of lead over the top and swaged it over the copper and it works well, but another step. I suppose you could use about anything that would compress over the powder. You could also use some type of plastic tip to plug the hole.

Dan

[sagacious]

To clarify very slightly, the stearate is not so much a "binder" as it is a lubricant. It allows the copper to compress more smoothly and completely during swaging.

An example of a binder would be the addition of tin powder to tungsten powder bullet cores. Under pressure the tin particles flow around the hard tungsten particles and bind to them, and bind them together tightly. The tungsten is too hard to bind to itself. Not all metal powders need binders or lubricants-- it depends on your application.

[Ammosmith]

I wonder if MSO2 would work as a binder?

[sagacious]

MoS2 would work as a lubricant, but not a "binder."

[acoop101]

what about using paraffin wax? mix it 50/50 to start with you could probably even get away with a whole lot less wax.

[sagacious]

If you used powdered/micronized wax, you'd only want about 1% by volume, well mixed-- but that would prevent sintering/annealing/heating of the swaged bullet, if desired.