What alloy drops bigger from mould than COWW?

[Les Staley]

COWW drops at .430 from my Lee mould. Doesn't shoot worth a durn in a Rossi 92 44 Mag. Gonna hafta go bigger. Bore slugs at .432 so looking for a bullet 433 or 434. Any suggestions? Would like to gas check. Thanks, Les

 

[yodogsandman]

linotype or hardball will cast bigger.

There's a chart half way down in this article...
http://www.lasc.us/CastBulletNotes.htm

 

[Rick]

You don't mention what alloy your using but the higher the antimony (Pb) percentage the larger the as cast diameter. We are talking .001" to maybe .002". Reason being is that the Sb alloy will shrink a bit less when cooled.

EDIT: Oops, yes you did say what alloy in the title. Be aware that high SB alloys are brittle so it can matter what your intended target is. Paper targets won't matter but steel targets it will and hunting it might.

 

[Brad]

I would buy a new mould. Does NOE have their version made for .432 in stock? That would solve the problem and let you use the alloy you have.

 

[Missionary]

Greetings
There are options to "help" your mold cast larger.
You can lap it out... easy with aluminum molds.
You can add a "spacer" between the mold face opening.
You could "dimple" the mold faces.
Many of us have done all these with happy results.
MIke in Peru

 

[Les Staley]

Thanks for the ideas. I've been reading up on lapping out the mould. Will try that first, as the Lee two cavity mould is pretty cheap. I'll have to be carefull that I don't oversize the gas check shank, already have some ideas on procedure. I think I'll pour the lap with the mould positioned in the jaws of my cross vice in the drill press with a cut-off screw in the chuck extending into the cavity. Will try it on one cavity, as the .430s will probably shoot okay in my 50th anniversary Flat top Blackhawk. Getting the mould to temp is gonna be a challenge, the vice being a huge heat sink. I'll take some pictures for the record when I try it.

 

[Brad]

When lapping a few voids aren't an issue.
I would beagle it. A little high temp Al tape on one side will gain .002 in girth right quick. Easy to reverse too.
Need some tape? PM me an address and I will send some. I use copper foil designed for stained glass work.

 

[GaryN]

I would beagle it also to start with. That will give you an idea of how it will work.

 

[fiver]

just grind the gas check shank off a previously cast boolit and use it as a lap.
smoke the mold.
lap till the smoke is gone. [probably 15-20 turns]
clean the mold and cast a few boolits.
measure them.
use them as your next lap.
taking the smoke off [I take the bluing off a steel mold] gives you about .001.

 

[Les Staley]

Brad, thanks for the generous offer of the copper foil. I have a roll of aluminum tape that you peel the backing off and it sticks. Should work. Will try Beagleing this mould. Will load a few without sizing and see what happens. Gary N, sounds like I may be on the right track. I made a couple of Lapps with some roofing screws with a hex head, and will drive them with a cordless drill. Took some pictures. Gun show tomorrow, so will post pics Monday. Thanks all for your help. Les

 

[Farmerjim]

Powder coat can give you a couple of thousands.

 

[62chevy]

Powder coat can give you a couple of thousands.

It sure does.

 

[James W. Miner]

Twist rate on the gun, might be barking up the wrong tree.

 

[Les Staley]

Twist rate on the gun, might be barking up the wrong tree.

James thanks for the idea. Background: Gun new about 2004. Wouldn't shoot .429 JSPs worth a darn. Called LSI for possible warranty. Sent it in, they put on a new barrel..shot it, no better than before. To heck with it! A year or two later kept thinking about it and was getting mad..called LSI again. They had a new outfit doing their warranty work, said "send it in". So back it went! Next barrel was a lot better, actually shot some two inch groups at 100 yds with JHPs. Took the gun to Hawaii on vacation, hunted Niihau Island with it, killed three Polynisian boars and two Morino Rams. (I in the meantime sent to Shilen for a .429 bore 1/20 twist barrel blank.) still a challenge to get lead to shoot in it! Will eventually contour and thread and chamber the Shilen, but I think it is POSSIBLE to shoot lead accurately in the third factory barrel, maybe have to cast a lighter(shorter) boolet for it. Seems like I'm barking up a whole FOREST!!!

 

[James W. Miner]

One thing to watch is mold heat, once your mold is filling out well, maintain a pace so it does not get hotter.
As you approach frosted boolits, they will be smaller. Slow down at that point.
Mold expansion is little understood because it is not a hole in a piece of metal, it is half a hole on an edge, metal expands to the edge but will enlarge at the parting line. Just makes a more out of round boolit.
Water drop or heat treat them and let sit a few days before measuring, WW metal will harden and expand.
Smaller calibers expand less but large can gain some, my .476" boolits actually reach .478".
A .429" should reach .430" and if you need more, Beagle or lap.
If you cast to full frost you are not doing yourself any favors. If you cast TL Lee boolits, you can see what hot spots do to drive bands.
I make my own molds and the cherries, Once I get the mold to temperature I drop the cherry back in to turn by hand with a wrench and you would not believe the metal I cut out. It makes my boolits larger and more round.

 

[Les Staley]

One thing to watch is mold heat, once your mold is filling out well, maintain a pace so it does not get hotter.
As you approach frosted boolits, they will be smaller. Slow down at that point.
Mold expansion is little understood because it is not a hole in a piece of metal, it is half a hole on an edge, metal expands to the edge but will enlarge at the parting line. Just makes a more out of round boolit.
Water drop or heat treat them and let sit a few days before measuring, WW metal will harden and expand.
Smaller calibers expand less but large can gain some, my .476" boolits actually reach .478".
A .429" should reach .430" and if you need more, Beagle or lap.
If you cast to full frost you are not doing yourself any favors. If you cast TL Lee boolits, you can see what hot spots do to drive bands.
I make my own molds and the cherries, Once I get the mold to temperature I drop the cherry back in to turn by hand with a wrench and you would not believe the metal I cut out. It makes my boolits larger and more round.

Very interesting. I'll try some more watching the heat. I was probably at or above frosting stage. Also been reading up on powder coating. If I powder coat after sizing, it should add some diameter and evenly too. Will keep on this. Les

 

[62chevy]

Very interesting. I'll try some more watching the heat. I was probably at or above frosting stage. Also been reading up on powder coating. If I powder coat after sizing, it should add some diameter and evenly too. Will keep on this. Les

I size after powder coating that way you don't have to lube, size then degrease before PC.

 

[James W. Miner]

PC is sure a cure but I have not needed it yet. I made molds to fit and a good lube works.
Do what is needed, have no fear.

 

[Les Staley]

Let's see...hunting.....shooting...reloading....bullet casting....rifle building...powder coating.....no more room for any more spin-off hobbies, but I can see that mould making....cherry making would be a natural extension..and FUN too!!

 

[James W. Miner]

It was quite an adventure. First I had to make a vise that closed to center and fit to my mill table. I bought two cast iron risers from a foundry. Big mushroom things. It took a few weeks on a stool in the yard with an angle grinder to make rectangles I could mill. Cheap cut off wheels on my body sander to remove excess.
Hardest cast iron I ever seen. It was very hard to cut the cavity to hold blocks.