Winchester 38-56 restoration help

Do you ever look at a rusty tool and think "what a shame" ? I do it all too often and buy things I don't need, just to clean them up and find an excuse to use them. This Winchester mold is just such an item, $10.00 on Etsy and so rusty I have been cleaning on it for two days just to see the Winchester logo and the numbers. I have high hopes and low expectations that this will cast good rounds. The two halves are slightly out of alignment and unless I squeeze it really hard you can see daylight through the top. I assume, rightly I think, that many of you have restored an old mold before, any suggestions would be much appreciated.

https://www.etsy.com/transaction/1331804654

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AlexAkai

I bought some MetalRestore at Home Depot. Dissolves that nasty rust leaving a pleasant grey color on the metal. Just the thing you are looking for here.

Thanks, I will have to give it a try

I have not messed with one that bad, but nearly so. I used Evaporust to clear up the rust. It may close all the way after the rust is gone. I usually lap mold halves against each other, maybe a bit of fine sandpaper pulled back and forth between the blocks could accomplish the same or on a piece a glass if you check regularly that they are staying parallel. Looks like you will need to make a sprue plate. Once you have that, you can cast a bullet and lap the cavity. It will remove most of the pits if they are not to deep and make it round again, but will be a bit larger diameter depending on how aggressive you lap it.

I have restored some pretty rough moulds. There are some things to remember. think hard about metal removal. Stones sandpaper files even steel wool all remove material.Cast occasionally with it to see progress. If the cavity is bad sometimes a couple thousandths from each face gives enough to lap it clean, Here remove a small amount and lap as lapping is a slow process and is easier in small amounts then checking. If you remove the whole .003 at once the it has to be removed from the cavities even if .001 would have cleaned it up. The top of the mould can be sanded clean if the stop pin can be removed. Or set it up in a lathe and center the pin face away from pin in light passes. The outside none working surfaces are easier and can be done. Any dings may be able to be worked out with a small rounded punch working around the edge of it moving the raised metal back into place. Working slowly and carefully that mould can be saved

Good advice here. I’m a sucker for old wrecks, too, if they are cheap.

The rust has to come off first. Evaporust will take off all but the deepest and worst rusting. I would try that first, and see if it solves the alignment problem. If you live at a low elevation, boiling the mould in water and scrubbing it off with steel wool as it boils will convert a lot of the rust to black oxide, loosen all but that in the deepest pits, and turn the surface rust into “rust bluing,” at least one layer’s worth.

I haven’t tried boiling a rusty part in Evaporust, but that might get more of it out. I do notice the longer I leave rusty parts in Evaporust, as long as it isn’t spent, the less rust is on them.

Check your alignment pin and its corresponding hole for dings and burrs. Some judicious work with a Swiss file on any bump on the pin and a little scraping on any raised metal in the hole should get the pin down to the bottom and may eliminate the daylight between the blocks. I use either the end of a drill of the exact size, in a pin vise, or the side of a slightly smaller drill, if none of them fit, for a scraper. Don’t make the pin any smaller, or the hole any bigger.

Burrs, nicks and raised metal on the faces have been covered in other posts. If everything looks flat and true, and there is still a gap between the blocks, some judicious squeezing of the blocks in a vise with copper jaws MIGHT bring them together again. I have done this with success, but there is, of course, the potential for disaster. Get only the backsides of the blocks in the vise; I usually have them in the center of the vise jaws, as deep as I can set them, with the handles (if integral) sticking up vertically.

You will need to make a sprue plate and screw. I’ll measure the threads on one of my moulds and post it later when I get to my thread gauge.

Then you cast a few boolits, drill the base of the best one, run a tap into the hole until it bottoms out, coat the boolit with Clover 320, chuck it in your adjustable drill or power screwdriver, and start the lapping process. I hold the mould in handles in one hand, the drill in the other, and gently squeeze as the lap is slowly turning. Stop often, clean the faces, and go by feel until the blocks squeeze together. The better your tap is centered, the less “lolloping” the mould will do as you hold it.

Clean the mould, cast a few more boolits and look for any improvements. If the cavity still isn’t satisfactory, take the best sample and repeat.

Winchester moulds were made to cast to the exact nominal groove diameter of Winchester rifles, so you have a few thousandths wiggle room for modern guns and lubrisizing dies. They were made of real steel, but people seemed to beat on their blocks more than I normally see on one-piece malleable-iron Ideals, although they were abused plenty, too.

About the only things I’ve seen that make the mould only good as blocks for a new cavity are deep gouges in the cavity itself by using the mould for pliers, or overenthusiastic scrubbing of the cavities with a wire brush or wheel, which enlarges the parting line on the block halves. Short of that, you can bring some truly hideous stuff back to utility.

You will probably wind up with a slightly oval cavity, with a few blemishes that you couldn’t entirely get out. So you won’t be able to use it in a CBA benchrest match. For all other purposes, it should do fine.

Thank you!

Here is where i am at:
1) used an ideal mold sprue cutter to draw a template for the sprue cutter
2) let the mold sit in Evaporust for 12 hours
3) cast a few rounds to see where I was at
4) dream up what to do with the cat rounds as I do not have a 38-56, so far Sabot'is in 12 gauge come to mind

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The head of the sprueplate screw on the Winchester mould I checked was 0.354” diameter, about 0.125” thick. The shoulder bearing on the screw that the plate swings on is 0.250” diameter, 0.130” thick. The threaded portion is 0.182” x 36 tpi.

Unless you want the authentic look, you might make the replacement plate with the knockoff tab on the right side rather than on top. I don’t have large hands, so I’ve found Winchester moulds kind of clumsy to use, with the widely spaced handles. Having to turn my hand so that tab on top can be popped open adds to the discomfort as compared to the Ideal moulds.

Give the Evaporust some more time. Almost all the red rust should turn to black slime with enough exposure.

Just noticed the telltale off-center gouge in the alignment pin hole and the corresponding ding on the pin itself. Somebody slammed those blocks together good! If you have a set of gauge pins, you may be able to peen some of that metal back by gently tapping smaller sized pins to the bottom of the hole and gradually increasing the size until you are using a gauge pin nearly the size of the alignment pin. A delicate operation, since you don’t want to enlarge the hole on the other side. If you don’t have the gauge pins, scraping is the only other choice, but with the gouge that deep, the hole will be enlarged some, and unless the alignment pin goes to the bottom of the hole, you might have some alignment problems.

The cavity actually looks good. The boolits might be a little speckly, but they should be perfectly useful. Good excuse to buy a Winchester 1886!

+1 Evaporust