shotgun slug mold idea

[defib]

I've been lurking for a while and have started to participate a little. I haven't cast any boolits yet but am aquiring equipment and lead. The info on this site is priceless. So heres my question.

I'm thinking about getting some plate aluminum and making a mold blank. ( 2 halves ) Then drilling them 0.687 in diameter and 0.750 deep. The bit would put a 60 degree nose on the slug. I would make a sprue plate from steel drilled and countersunk.

This is for a smoothbore 12ga. I want the slug to be shot in a wad cup in a 2 3/4 shell. I'm looking at going ferrel hog hunting in june.

Any ideas would be welcomed, even ones that say this is a bad idea.

thanks!

[missionary5155]

Good morning defib and WELCOME !
It all sounds good... I have shot .685 Round Ball for years using shot cups. You want to have a Snug fit going down the barrel. I generally try for .005 overbore diameter. .007 or more does not add any accuracy and does show more pressure. But whatever you do... start out with a low power load and work up. Adding One grain at a tme does not seem excessive. But be consistant. If you are looking for about 1300 fps then powders around Unique work well. Faster switch to Bluedot or similar burning powders.
I think if you are going smothbore a Round Ball will serve you better. BUT hey go for the mold making. I just do not see a Boolit flying well past 20 yards without rifling. They need spin stabalization. Round ball will fly well out to 50 yards from a smothbore. Some combinations of RB will get farther but require more work. A WW ball will penetrate a hog from most angles and they are so easy to cast.
Head down to the shotgun section ... there is about 2 days reading in "Casting for Shotguns".
Dixie has a GOOD handle on 12 Bore boolits. Longbow has GREAT stuff on full bore RB. Others have SUPER ideas and results. Me I get to glean out ideas and give-em a try.
God Bless you !

[cuzinbruce]

If you are just starting, you might want to consider buying a mold for this. You can buy a Lee .690 Round Ball mold or two sizes of 12GA slug molds from MidwayUSA for less than $20 a piece. Simpler and quicker, maybe be even cheaper too.
Don't forget on making a mold, you have to figure out handles and pins or whatever to align the two blocks.
Good Luck with the project.

[MtGun44]

In theory it's a good approach, but the practical problem will be getting the
drill exactly in the parting line to within about 0.001-.002 inch accy.

Bill

[MakeMineA10mm]

Also, there is a little more to boolit design than making a hole in the mould. Have you considered how much that slug will weigh? Out of what alloy? Will you be able to find load data for it? I haven't run your numbers, but that could wind up weighing a couple ounces... (A LOT more than standard moulds.)

I agree with cuzinbruce. For what you're wanting, I'd get the Lee key-drive slug or the Lyman 12ga. "pellet" slug (it looks like an enlarged air-gun pellet). Both of these moulds are designed to work with shot cups.

[Cap'n Morgan]

In theory it's a good approach, but the practical problem will be getting the
drill exactly in the parting line to within about 0.001-.002 inch accy.

For a straight-side slug, a two-part mold shouldn't be necessary; a pure lead chunk of this size should shrink enough to drop from a solid mold.

[Blammer]

should.....

what I'd do it drill a hole through the bottom of the mould then put a "pin" in it that makes for a flat nose section. Then when it's cool, just "pound" the slug out with the pin. :)

of course it's just a wild idea.

[Willbird]

I have not made my first mold yet, but in making many other things it is typical that you might just as well hack out the first one, and thus learn how to make the next one.........better :-)

You COULD screw a washer cut from 1/2" or thicker celotex to the base end to help it fly straight :-)

Bill