Cast Iron Ideal molds

[castmiester]

do they cast over sized ? like the newer molds ?

[RickinTN]

It's been my experience it's hard to get one to cast large enough usually. This of course can vary.
Take care,
Rick

[john.k]

Its not that difficult to chuck up these old iron moulds in a lathe and make them larger ...carefully..................the first one i did was a single cavity 44 ....427 dia,and the faintest touch made it cast 435 .............after that ,I had complete success with removing gas check s and enlarging bases a few thou......a very delicate touch is needed ...just making dust is going to be 003 larger.

[Hick]

I have the old ideal 358156 and also the 321427. Both cast just slightly oversize. Just enough that I can run them through a sizer to make sure they are uniform, but little press pressure.

[castmiester]

Its not that difficult to chuck up these old iron moulds in a lathe and make them larger ...carefully..................the first one i did was a single cavity 44 ....427 dia,and the faintest touch made it cast 435 .............after that ,I had complete success with removing gas check s and enlarging bases a few thou......a very delicate touch is needed ...just making dust is going to be 003 larger.

And on a tail stock what ? How do you work the cavity to over size it? I ran a sheet metal screw in a cast to polish the cavity with lapping compound.

[john.k]

Simply bore it out with a tiny boring bar ............I intend to try some Lee molds ,have to drill the pin to separate the handles ,going to increase a 45 to 475 for the Martini.........might be the single cavity HB 457/400.............Lee could very easily do the same thing ,but the Martini market isnt big enough.

[castmiester]

Simply bore it out with a tiny boring bar ............I intend to try some Lee molds ,have to drill the pin to separate the handles ,going to increase a 45 to 475 for the Martini.........might be the single cavity HB 457/400.............Lee could very easily do the same thing ,but the Martini market isnt big enough.

DUH !! the driving bands only need the enlarging !

[longbow]

In my experience new Lyman moulds cast undersize or at best to size.

Not sure about Ideal moulds but my old Lyman moulds cast larger than my new Lyman moulds. I have a 40 year old 31141 that casts at 0.310"0.311" with ACWW which is fine for a 0.308"/0.309" groove diameter but when I bought a new Lyman 314299 a few years ago it cast at 0.312"/0.313" with ACWW. Yes, it may cast 0.001" or so larger with Lyman #2 alloy but in my view it casts undersize. Even with Lyman #2 alloy it would be marginal at best to cast 0.314". Oddly my Lyman round ball moulds for 12 ga. (0.662", 0.678", 0.715", 0.735") all cast oversize by at least 0.002" with ACWW.

I'd say that machining out driving bands would be a delicate operation and difficult to repeat on each driving band unless you have a good lathe with no backlash and a pretty good skill set since you are working blind in the cavity. Lapping out a couple thou is easy.

Longbow

[deltaenterprizes]

Lapping is not hard but time consuming by hand. A drill can speed up the process but it may be tricky to get consistency in a multiple cavity mold.

[JonB_in_Glencoe]

Mostly, modern Lyman molds that I've owned, cast the advertised size. I've had a couple that were undersized, but when asking others here, they had same issue with those specific mold designs being undersized as well. I've had about 6 or 7 Ideal molds, most of those cast as advertised or .001 larger.
that's my 2¢

[castmiester]

Mostly, modern Lyman molds that I've owned, cast the advertised size. I've had a couple that were undersized, but when asking others here, they had same issue with those specific mold designs being undersized as well. I've had about 6 or 7 Ideal molds, most of those cast as advertised or .001 larger.
that's my 2¢

Hard to find the Ideal molds on ebay or gunbroker..... I looked on here too.

[Larry Gibson]

Many of the old, old Ideal moulds were cut #1 alloy [lead, antimony, tin and copper] or for a binary lead-tin alloy. Both of those alloys give greater shrinkage in the mould when solidifying than do ternary alloys, especially those alloys with a balance of antimony to tin. Hence, with ternary alloys they usually cast larger diameter "as cast" bullets. For example, my older Ideal 311466 and 311465 drop bullets cast of #2 alloy at .313" diameter.

[JonB_in_Glencoe]

Hard to find the Ideal molds on ebay or gunbroker..... I looked on here too.

You can't just go look for them, they need to find you...and they will when you least expect it.

I just sold a sweet Ideal 311334 on S&S last month...and for cheap too.