Classic Lyman spru cutter screw movement "cured", so far.

[prs]

Months ago I asked for advice on keeping that pivot screw locked into place. I did not then realize it even had the Allen screw to pinch-lock it in the desired tension postion. One response I received advised using a piece of 7 1/2 shot under that Allen screw. The other was to adjust the pivot screw just right, mark the side of the screw head were the Allen sould mate, and then flatten that side of the bottom of the screw shank with a flat file. Well, I had two offending molds, so I flattended the screw shank on my 452374 and used a 7 1/2 magnum shot under the Allen of my 452460. Mostly been using the 374 and forgot all about the "problem", mold works gread over several sessions. Yesterday, I used the 460 and it failed again after going through about 40# of alloy. The lead shot had melted. So now, both molds have had that pivit screw's lower shank flattened so that the Allen has a secure mating with it.

prs

[BACKTOSHOOTING]

You could just cut a piece of solid cooper wire and use the same way as the shot, Works great for me

[leadman]

The problem I found with all of the Lyman moulds (old & new) I have checked is that the hole for the allen screw is not threaded out to full diameter. This causes the allen screw to bind in the threads just as it is tightening against the pivot screw. Lyman must only use a taper tap to thread this hole.
I use a bottoming tap to clean the threads out to full diameter and that is the end of the problems.

It is easy to check for this. Just remove the sprue plate and pivot screw and try turning in the locking allen screw, then look in the hole for the pivot bolt and see how far the allen screw extends into it.