I just received a Lyman 257464DC mould that has a problem. When you hold the mould halves together and look down the cavities toward a bright light, the cavity furthest from the sprue plate screw, shows a little "daylight", the other cavity not so much. I installed 2 different sets of Lyman handles, an RCBS set and a Lee set, to see if a little pressure would eliminate the problem, but alas, it does not. I noticed that the right block, the one without the sprue plate screw, does not move easily on any of the handles, but is rather rigid. The other block swings freely as do most of my moulds.My thought WAS that the hole drilled thru that right block may not be in the correct location, preventing complete closure. BUT how does one explain that the two halves do not mate properly without the handles?
I tried twisting the halves to see if there was any pin slop and there is absolutely none! The mould surfaces also appear to be clean and free from any foreign matter.
Any suggestions on what's going on here and how to correct this problem?
The owner of this mould has given me permission to put a dimple on the nose of one cavity in order to distinguish which cavity a given boolit droppoed from. I'll take some measurements of the various diameters as cast and see what happens.