Fixed a Lyman mold today

[Fritz D]

Years ago I bought a used Lyman 287448 mold at a gun show . . . it looked good but it turned out to be a lemon (probably why it was for sale). The mold halves did not line up properly, so it cast a very out-of-round bullet. There was a very noticeable step where the 2 halves of the bullet came together. Over the past few evenings I've been playing around trying to figure out if I could improve things. I checked the alignment pins/holes but they were fine. I tried driving the pins a bit farther out but that did not help anything. With the mold closed, the blocks (and the cavity) were visibly out of alignment. Long story short . . . I removed the pins, carefully lined up the mold halves, clamped them in a machinist's vice and re-drilled the 5/32" factory holes up to #20 (.161"). I made new pins out of a couple of broken taps I had (that just happened to be the right size). Before this surgery, the bullets were .0035" bigger at the seam. Now they measure .289"-.290" (Linotype alloy) all the way around. Not perfect, but I'm really pleased with the results. I'm sure I'm not the first person to ever do this, but I thought some might find it interesting.

95292

95294

95293

[DLCTEX]

Great fix. Thanks for posting.

[Catshooter]

Nice work, nice contribution to the site, and welcome to it.


Cat

[williamwaco]

Years ago I bought a used Lyman 287448 mold at a gun show . . . it looked good but it turned out to be a lemon (probably why it was for sale). The mold halves did not line up properly, so it cast a very out-of-round bullet. There was a very noticeable step where the 2 halves of the bullet came together. Over the past few evenings I've been playing around trying to figure out if I could improve things. I checked the alignment pins/holes but they were fine. I tried driving the pins a bit farther out but that did not help anything. With the mold closed, the blocks (and the cavity) were visibly out of alignment. Long story short . . . I removed the pins, carefully lined up the mold halves, clamped them in a machinist's vice and re-drilled the 5/32" factory holes up to #20 (.161"). I made new pins out of a couple of broken taps I had (that just happened to be the right size). Before this surgery, the bullets were .0035" bigger at the seam. Now they measure .289"-.290" (Linotype alloy) all the way around. Not perfect, but I'm really pleased with the results. I'm sure I'm not the first person to ever do this, but I thought some might find it interesting.



I would respectfully disagree. I would consider that perfect.
It is a rare mold in my experience that is "rounder" than that.

[JASON4X4]

Good job

[Ben]

You get an A + on that job.

GREAT work !

Ben

[Bzcraig]

I wish I had the skills and knowledge to do that.

[Fritz D]

Thanks for all the compliments. Maybe now I will get to use up that box of Hornady gas checks I bought ages ago!

[Teddy (punchie)]

Let know us how shes shoots for you.

What size tapes? #20 how many .000 is that?

Nice post !! Thanks !!

[Dale53]

Teddie;
He gave the size of a #20 drill in the first post as .161"...

http://www.gearhob.com/eng/design/drill_eng.htm

(Google is your friend[smilie=1:)

Dale53

[guicksylver]

Good Work ! Guess I was lucky, driving the pins out further fixed mine.

Then again !, they shot really really well ( Like sub moa @ 100 yds) when they were out of round.
Just trying the "fixed" boolits this weekend.

Fingers are crossed.

[Fritz D]

What size tapes? #20 how many .000 is that?

#20 drill makes a .161" hole. The taps I used to make the new pins were 6-32 and 8-32 (they both happened to have the same size shank). They were very roughly ground and varied over their length from .1615" up to .164". I chucked the pins in my lathe and using abrasive cloth, carefully worked them down. I made them as close to .162" as possible. They are not as snug as the factory pins, but I cast approx. 200 boolits yesterday and so far the pins have not moved.

[gray wolf]

Nice work, thank you, never to old to learn Eh.

[TXGunNut]

Good job! Thanks for sharing.

[phaessler]

Good Job! Nice to see some quality work saving an old mold

[Fritz D]

Again, thanks for the compliments.

[Walter Laich]

nice to hear when a plan comes together

[Echo]

A Big Way To Go! Thanks for the post.