project - core mold, need some advice

[JBMauser]

I will admit that I am cheap and do not have anything larger than a DC, There I've said it. Now I bought some 1/2in. thick al bar stock and have a vague description of how to build a core mold but I need some more data or pics etc so I can dope out how to build a proper 6 gang sprue plate and how to rig bottom plugs to some kind of screw mechanism to varry the length. The Goal is to cast lead cores to swedge into 45 cal pills that I may paper patch for my 45/70 rolling block. If it works out I will try to make .30 cal pp pills with another mold. Also could use some ideas on handles... Anyone been here before? Thanks in advance. jb

[Bent Ramrod]

JBMauser,

Sorry, I don't have one of those pixel cameras. However, I have a 4-cavity Corbin core mold for casting .22 slugs. All dimensions are approximate below.

The main part of the assembly is a 4" long piece of 1" x 1" mild steel stock with four 1/2" holes drilled in it, equidistant in a line in the center. At each end it is drilled and threaded for a 1/4" bolt. The steel stock is bolted to a 7-1/2" strip of 1/8" thick, 1" wide steel, held off from the strip by a pair of 1-1/2" long, 5/8" diameter cylindrical spacers. The steel strip has four 5/16" holes drilled in it, equidistant, such that they are in line with the centers of the holes in the steel stock when the parts are bolted together. The unused other end of this strip is clamped or bolted to a bench top.

In each of the four 1/2" holes is a 1/2" piece of round stock, reamed in the center to somewhat less than .22". These cylinders with holes are the core molds in which the lead is cast. These are held in the holes in the steel stock with set screws such that the tops of the cylindrical pieces are even with the top of the steel stock. Sliding up and down in each of these holes is a steel rod turned to a close fit and threaded perhaps 10-24 (don't have gauge handy). Two nuts are fixed to each threaded rod so that they stop the drop of the rods against the strap at the bottom at any depth desired, and can be jammed together so as not to lose the setting. The excess length of threaded rod sticking down through the holes in the strip is used to push the castings up and out of the holes.

Finally, a similar strip to that on the bottom is bolted at one end to the top of the 1" x1" x 4" steel stock. Four holes are drilled in line with the mold holes and a hog-wallow milled between them for pouring the lead and collecting the sprue. A roundhead screw attached to the side of this strip stops the travel of this sprue cutter as it pivots on the bolt. The excess length of this cutter is in the opposite direction of the strap at the bottom and provides (needed) leverage for cutoff.

Little as I'd use it, I gotta get one of those pixel cameras someday. A picture is indeed worth 1000 words:) .

Your six-cavity for .45 caliber would be a scaled-up and beefed-up version of this setup (I surmise). I have no trouble pulling or tapping the sprue cutter to cut four .22 cores, but six cores at about .40" each might take some beating to cut. Also, those little core holes are not all that straightforward. Something happened to one of them such that the core would stick in it. Couldn't see any damage, but polished away with crocus till the inside shone. It is still kind of balky, especially when fully heated. So do a good job of reaming on those holes in the aluminum (if this is the way you are going to do it) and avoid galling or scraping of the push rods and sprue cutter at all costs.

Hope this helps. There may be a picture on Corbin's web site; he's incredibly helpful.

Bent

[454PB]

I have one of the Corbin core moulds as described above, and I have a couple of digital cameras. If you would like, I can take a picture and post it for you.

In my opinion, they are not user friendly. I fought mine for several hundred cores, and finally gave up on it and started buying lead wire instead. I compared accuracy between my home made .22 jacketed bullets using cut cores and cast cores, and it was no contest.

I bought 50 pounds of .22 caliber lead wire, so I'm fixed for a long time. I can see where .45 caliber wire might get a bit pricey.

[Buckshot]

http://www.fototime.com/05939E361C30577/standard.jpg
http://www.fototime.com/33E1CE1D5D95675/standard.jpg
http://www.fototime.com/9CDD1C8B75E1C5A/standard.jpg
http://www.fototime.com/69EE11C0C86C987/standard.jpg
http://www.fototime.com/2B2A7A2010AD1E9/standard.jpg

.................Buckshot

[JBMauser]

Buckshot, thanks ..... this is exactly what I need. It looks as though the end of the sprue plate rises over the top of the top of the handles. does it require a lot of force to knock the plate free and cut the sprues? how deep into the blocks do the handle shafts run, are they really that close to the edge of the stock: I really like your hinge. Thanks tons, my brain is in gear.... JB

[Buckshot]

Buckshot, thanks ..... this is exactly what I need. It looks as though the end of the sprue plate rises over the top of the top of the handles. does it require a lot of force to knock the plate free and cut the sprues?

..............No, but I've only used 1-20 as the hardest alloy. Usually it's pure or almost pure lead (maybe a teensy bit of tin).

how deep into the blocks do the handle shafts run, are they really that close to the edge of the stock:

.............I don't know, and I'll bet they're stepped down.

I really like your hinge.

............I didn't make it. The core mould is from RCE (Richard Corbin Enterprises). They cost $80 at the time I bought them, which was several years ago. The only things I did was to add those 2 spring steel 'L' brackets. If you notice there are no alignment pins. The base and sprueplate are supposed to keep the blocks aligned. They do so pretty much, but those brackets make sure they do, very well!

Thanks tons, my brain is in gear.... JB

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