Unusually tight Lyman mold

[Jim]

I received a Lyman 457406B from a friend and ran a few off yesterday. The blocks are incredibly tight. The first few that came out were finned, so I started looking for the problem.

The blocks won't close completely, even with moderate to heavy pressure on the handles. I had to tap the handles with my hickory stick while squeezing the handles to get the blocks to close completely.

Once I got that worked out, I found that I had to apply heavy pressure to get the blocks to open. Once the blocks opened, the boolits fell right out. The boolits looked fine once the blocks are closed completely.

I don't have a lot of experience with Lyman molds. The few that I have function fine and make good boolits. What do I need to look for and do to make these blocks open and close smoothly?

Thanks, fellas.

[oneokie]

Alignment pins need adjusting. Measure the protrusion and start driving them into the block they are in.

[Wayne Smith]

Alignment pins need adjusting. Measure the protrusion and start driving them into the block they are in.

Or specks of lead in the aligment pin hole in the opposite block.

[runfiverun]

sometimes just a push on the corner of the mold will help them open easier.
but i'm gonna go with the alignment pins being a bit too far out.

[Iron Mike Golf]

Also, check for bruising/burrs on the edge of the bushing the alignment pin fits into.

[geargnasher]

Also, check for bruising/burrs on the edge of the bushing the alignment pin fits into.

+1, except they're not bushed on those, just drilled holes. It probably looks like a moon crater around the holes, and someone may have already pressed out the pins to seat more deeply in order to elminate sloppy fit from the wear, and now they're out so far they bind. If you're careful, you can peen the raised metal back where it belongs, de-burr and uniform the edge of the hole with a countersink, and reset the alignment pins to the correct depth.

What handles are you using, Jim?

Gear

[Jim]

I got it straightened out. I cleaned the pin holes to 'brand new' and then chamfered the edges. Snaps right together, now.