View Full Version : Question on Old Lyman Mold
March 6, 2010, 09:19 PM
I have an old Lyman mold #358242 I think I bought in the early to mid 80s. It is listed as a 121 gr. and has a RN configueation. I just got back into casting after years of shelving my equipment. I cast some bullets from this mold today using wheel weights and they dropped at .3555 and weighed 129 gr. I'm guessing the undersized diameter is due to the material (wheel weights)? I'm thinking of using these in both 38 Spl and 9mm. Anyone see a problem with that use?
March 6, 2010, 10:14 PM
Undersized bullets will probably lead your barrel terribly. Generally, you want you bullet sized .001 to .002 over groove diameter for best results. You need to slug your barrel to find the groove diameter. The harder the alloy, the larger the bullet drops from the mold. Pure lead drops smaller bullets than WWs. I have had great luck shooting .001 over GD in 38 and 357 mag...and .002 over GD in 9mm. As far as the weight, diffeerent alloys will yeild different weights. It is no problem that it drops heavier than advertised...just make sure you use the right load data. You can probably find 130 grn load data...and if not, you can use 125 grain load data CAUTIOUSLY. Good luck!
How to slug a barrel: http://www.youtube.com/watch?v=CR_WiL8Dkgw
March 7, 2010, 08:19 AM
I use cast (ww + 2% Tin) 125 round nose bullets in my 686 .357 all the time with a light load for plinking. I have no problems using them. They drop from the mold at about .357 though.
March 7, 2010, 08:58 AM
Everything Coyote said is exactly right. The more tin the larger the as cast bullet will be. Your problem may be you are leaving the stick on WW in the mix. Those things are almost pure lead. I pick them out and use in the Muzzle loader. But if you want to leave them in. you will need to up the Tin. Straight clip on WW should drop a Bullet close to Lyman #2. Which would be about .358. Maybe a little smaller. But the .355 means you have a lot of pure lead in them.
March 7, 2010, 09:32 AM
Hornady-actually I always seperate the stick on weights from the clip type. Have for years. I shot some of these in three handguns yesterday (all 357) with light 38 spl loads and no leading problems were visable. I've loaded some light 9mm loads up so the next time I get to the range I'll give them a go. I'm just surprised they are dropping undersized as typically all my other molds drop oversized and then I size for .001 over. It really isn't a big deal as I have another 358 mold for 158 gr SWC I have been using that drops a bit oversized using the same material. Since I had the smaller mold I just thought I would use it for plinking bullets and save some bullet material.
March 7, 2010, 10:25 AM
On Lyman molds such as the 358242. The 358 is the diameter of the bullet as cast with Lyman #2. So if its dropping a .355 bullet. It must either be. A bad batch of lead. Or the mold is not Right. I would think the Lead mix. I know I am seeing more of the stick on weights. In the WW, I collect. But also. Talking to guys. Weights from different parts of the Country. Have higher or lower Tin content. Tin being very expensive. I can see where Manufacturers would be cutting back on the Tin in Clip on WW. I add Linotype to my bullets. Antimony content is high. So the bullets are harder than need be. But its also a good source for cheap Tin. WW are about 0.5% and Lyno is 3 % with the WW and Lyno I only need a small % of added tin to get to my goal of close to5%. Which is what Lyman #2 is.. As too leading . Even with under sized bullets and that is the main cause of leading. It usually will not start getting Bad until you get over 50 rounds. Some times not until a 100 or more.
March 7, 2010, 09:31 PM
Is the mold clean??? most old Lyman /Ideal cast over with any decent alloy !
Check to make sure it`s clean then as suggested add alittle tin(over 2-3% does`nt help it only wastes tin) & cast a few & check em befre ya cast a bucket full!!!
Even try a different alloy if possible!
I shot some commercial cast swc in my 357 (hey they were free) & checked 3565 , I pushed em hard to get em to bump up but noway too hard !!!
Leaded all my barrels from end to end!!!!
I kept em to add to my stick ons, the lube made good flux !!!:D:D
March 8, 2010, 02:04 PM
I have a 358242. Mine drops from the mould at .359" with straight WW's. They also made a 356242. Maybe they miss stamped it. You can always lap the mould. http://www.midwayusa.com/viewProduct/?productNumber=445760
vBulletin® v3.8.7, Copyright ©2000-2014, vBulletin Solutions, Inc.