Curious finding

[Blackwater]

Last night I had a curious thing happen. A buddy had problems with his Lyman 457125 mould. It's new. He said he couldn't get a good bullet from it, and sent it to me asking me to give it a go and see if I could make it work any better. I cast a little over 150 bullets, using 30% WW's with pure lead and @ 2% tin added, and two temps with 20:1 lead/tin. All bullets with the partial WW metal had finning on the nose. Most of those with the 20:1 had finning. Before casting, I noted I could see light at the nose end of the mould when I had it "closed."

Not really knowing why, I whimsically decided to try the mould, after it had cooled enough to handle it, on an old set of Lyman 1-cav mould handles - it's a 1 cav. mould, and I guess I just wondered what would happen.

Surprise! The mould shows no light now when closed!

The handles I'd used for casting were a newish set (@ 3-4 yr. old) for 2 or 4 cav. moulds. I'd been told, and probably read too, that these could be used for SC moulds. But then .... there's my results.

Question: Have any of you had this happen, and if so, how do you explain it? Is there some difference that escapes me (not to hard to do) that I haven't noticed? Whahhoppened???? I'm stumped.

Haven't had time to measure anything yet, but with all the experience around here, I thought this was the place to ask. Somebody may be able to save me time and confusion .... hopefully.

[waksupi]

Blackwater, I've had this happen when changing handles. You may need to grind a bit off of the inside of the handles, where they go in the blocks. Most likely, just from the screw hole, to the end of the prongs. Sometimes there is just enough interference to prevent full closure.

[NVcurmudgeon]

Blackwater, I haven't dealt with your exact problem, but I have had the opposite one. I have several old single Lyman moulds and several old Lyman single handles. They all work just fine. Lately I have added a couple of new Lyman double cavity moulds. These work with the old single cavity handles with a bit of filing. It's not very difficult to eyeball where metal needs to be removed. Mostly, the handle needs to be thinned from about the hole where the mould screw goes through, back to where the handle begins to thicken. some need the forwardmost part of the thickening of the handle thinned, as well. The modified handles then work with both single and double cavity moulds. Working with old and new Lyman equipment is a lot like installing mixed year parts on early Volkswagens. Just as the little car that never changed, really changed every year, Lyman/Ideal has been in business since before smokeless powder and has changed everything!