Casting a bullet mold

[necchi]

Anybody know how much aluminum will shrink?
Try to make my own mold.
3d printed this last night

There are many occlusions in the print you have shown us.
Why are you asking about aluminum?

 

[eggwelder]

In my experience, aluminum will shrink about 1/16 of an inch over a 6 inch length. I think your idea will work if you pay close attention to what you are doing, which you obviously are. you`ll need to oversize the patterns a touch, and need a cutter to finalize the shape of the cavity after you mate the two halves. There are ways to center the cutter to the mold that were used prior to CNC, milling machines, etc. Doable if you are handy.
personally, i would have made the patterns from wood with a basic centered cavity that i would drill out prior to reaching final internal dimensions, then use the cherry to finalize the cavity in your desired shape.
much nit picky work, but if you enjoy it- go for it.
I made a soapstone mold for my .32 cal. It worked well, but a bag of buckshot worked better, and for best results, i have a .313 lyman mold now that is a perfect fit for the 32 when COWW lead is used.

 

[Treestalker]

How about the brass two piece mold made to order to whatever dimension of ball you like. Set up to work with Lee loaded handles. Saves a lot of problems with casting. You could make a mold from aluminum on a drill press I suspect.

Couldn't a brass/aluminum mould be recut from a smaller diameter RB mould? How about Dixie's blank 'scissor' type mould of mild steel? I used to have one but sold it, I wish I had kept it to be buried with, so I could avoid bullet shortages in the hereafter, LOL!

 

[Treestalker]

Wow Zonie I feel like Gilligan listening to the Professor after reading that explanation! lol

You guys are awesome, what a wealth of knowledge here

That's why engineers are so valued. Can you imagine having to do all calculations on a slide rule instead of a computer? I worked in a soils laboratory in the late '70s in which the results were achieved on an 11 decimal place calculator.

 

[jcs266]

That's why engineers are so valued. Can you imagine having to do all calculations on a slide rule instead of a computer? I worked in a soils laboratory in the late '70s in which the results were achieved on an 11 decimal place calculator.

I have my grandfather's old slide rule and have tinkered with it a bit. It blows my mind first of all who it was who designed the Slide Rule (what an amazing mind to come up with that!!) and secondly what it can do... WOW!

 

[The Crisco Kid]

Another option is a $15 made in China 12.5mm (.490) ball nose mill bit and 2pcs of aluminum.

That's a good start but unless you have quite a bit of machining experience and the right machines you'd better have some extra aluminum to practice with. I didn't have either the experience or really good machines but I still managed to make a mold that cast a fairly good bullet. The two problems I encountered were getting the cavities exactly halfway into each block so that the bullet wouldn't hang up and allowing for the thread lash in the equipment which gets things out of alignment. I'd also not expect a $15 Chinese endmill to be truly round or to run without any wobble. In that case you will be doomed from the start.

 

[Davey Boy]

Don't be so quick to down the China endmill

Remember American Companies transferred knowledge and manufacturing out of the U.S.

The tooling, materials, and quality I see from China puts the crap we do like some kid living in a tent made it

And up until recently, the prices for Chinese goods was extremely affordable

 

[The Crisco Kid]

Yep, the Chinese do make some very good products and sometimes they send them here. However, the wobble in some of my new Chinese drill bits that I bought at Harbor Freight do "The Twist" better than Chubby Checker himself.

For those of you to young to know:

 

[Davey Boy]

I am looking for soapstone good quality, 2 pieces. About the size of a bar of soap.

I think it will be good material for casting lead

I have used plaster of Paris to make 1 1/2" cannon balls from poured lead. Get about 3 or 4 before they are not good enough.

I am thinking a piece of flat metal with a hole in the center. Mount it in a forked holder and peen the axle at each side so it turns straight.

Hold it like a tire on a grind wheel and let it skip along until it gets a round shape.

Once round keep making it smaller and check the diameter against the barrel bore

When it is the size of the ball size you want, grind a cutting edge so it isn't flat like the side of a washer

When done, peen the axle so it can't rotate

Now you have a cutter that can bore into the soapstone

 

[ohio ramrod]

Another option is a $15 made in China 12.5mm (.490) ball nose mill bit and 2pcs of aluminum.

Before I retired as a tool and die maker/tool grinder I made some .440 and .490 ball end mills which I used to make molds from aluminum blocks plus I made some mini molds on my lathe. A lot of time but worth the effort for the satisfaction of making my own molds.