Lyman 45 Mis-Alignment with new Dies?

I purchased a Lyman 45 at an auction about a year ago, and cleaned it all up and removed the 267 die that was mounted in it. I currently use an RCBS Lube-Sizer and most of my sizing dies are RCBS and later model Lyman dies. I discovered that the original die for the Lyman 45 press is precisely machined to fit in the press, as the clamping screw pressed the die to one side. The newer dies are machined several thousandths smaller in diameter, using an O-Ring to take up the space and center the die and designed to work with the current large nut hold down from the top, as RCBS has used since the beginning. Since the clamping screw will not allow me to use the newer O-ring dies without miss-aligning the die by several thousandths, do I need to buy the old dies to work in this Lyman 45? Or is there another solution?

If the newer die has the o-ring and a sloppy fit, I put it into the lubrisizer, put the top punch in its socket, pull the lever down until the top punch goes as far as possible into the die, and then tighten the set screw just enough to set it lightly into the groove in the die, but deeply enough to keep it in.

The die will “float” up and down (and slightly from back to front) in use, but the o-ring will keep it from leaking; at least any more than the 45 will leak normally out of its other joints and surfaces. I use the minimum pressure on the wrench and restrict the 45s to softer lubes, leaving the modern higher-pressure/heating needed concoctions to the Lachmiller, or to whatever newer lubrisizer holds the die in with the annular nut. (By the way, I use the same top punch indexing on the Lachmiller to get the annular nut started straight in its threads, which can be a problem otherwise with the new die protruding somewhat and lube all over the place from the changed out die.)

Sizing the minimal amount, no more than 0.003” helps as well. Under these circumstances, the casting tends to center itself in the die. Hope this helps.

I use a couple of RCBS lubesizers to lube bullets. I do not try to size or appy gas checks because I tried until I was blue in the face to get evenly sized bullets and it won't happen. I do all of my sizing in a Lee push through sizer and then apply lube in a die .001" to .002" larger in diameter. I get evenly sized bullets this way. I understand that NOE also offers a system in which to push through size but I have no experience with it.
Good Luck!
Rick

Quote:

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Originally Posted by DonMountain

SNIP>>>
The newer dies are machined several thousandths smaller in diameter,
...
the clamping screw will not allow me to use the newer O-ring dies without miss-aligning the die by several thousandths,

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I only use Lyman 45 lubesizer press's. I haven't ever noticed I had any new O-ring style dies where the OD on top was several thousandths smaller. Just now, I had to double check. I picked a couple dies randomly, one new and one old. The top of the new one was 0.720 and the top of the old one was 0.722
The O-ring in good condition, even when compressed into the press, should take up the 0.001" space around the die just fine, but you don't want to over tighten the set screw.

I wonder if your Lyman 45 sizer die port is over sized?
Is it round? ...or slightly oblong?
Maybe a previous owner has over-tightened a die and "stretched" the sizer die port on your press?

My 45 dies stick up a few .100 and measure .724 on top and .703 at the bottom. I measured a 450 die and it was .695 at the top and others different. My 45 dies have no 0ring and snug fit. Correct 45 dies are hard to find at a good price. My set screw contacts the groove what some people think is where an 0ring goes. My 450 dies measure different sizes so 0rings need to be correct for leaks. 45 dies need to be sized more precise to work.