Hello out there in Reloading land...

[TheOldGreybeard]

Greetings from sunny (for a few minutes) Oregon. TheOldGreybeard here. Started reloading in the mid 60's, and around that same time a fine shooter/gunsmith from Nebraska taught me how to cast bullets for my .357. I thought I knew something about it after 45 years or so, but now I"m not so sure....
I mostly cast for action shooting (IDPA and Steel) matches here in Eugene, but have tinkered a bit with rifle bullets over the years. I have been having trouble with the molds filling smoothly in the last couple years, and think it might be zink contamination. One of the young shooters in our club pointed me toward this forum, so I think I'll see if I can make the melted wheelweights work better after cleaning up the alloy some, perhaps with Sulfur...
I also have a LARGE number of gas checks from an estate which I will post for sale when the proper time has elapsed. These are mostly in various rifle caliber sizes.
I have been a member of The Varmints Den forum for several years and also sell on Gunbroker when I have something appropriate to that method...

[versifier]

Welcome to Gunloads.

If you have alloy that is actually contaminated with zinc, then there is no practical way to render it usable that I have ever heard of. (They will make good fishing weights, if they are still legal to use there, and if you have a swaging press, they will work for that, but that's about it.) I only had one contaminated batch and that was enough. Fortunately it was a small batch, only 30lbs. Now I presort the WW's, tossing everything that even looks suspicious. I watch them like a hawk in the smelting pot for when the clips start to float and then skim everything floating as quickly as possible - zinc is less dense than lead and always floats in case I miss any in sorting.

However, before you despair, put a small amount of the suspected alloy in your casting pot and add some (2-3%) tin to it (bar solder, pewter, etc.). See if that cures the problem, you have nothing to lose by trying it. Sometimes you will have fillout problems if there is not enough tin in the mix, round corners, etc. I will usually add some to a full pot of WW ingots just to be sure. I even add 1% to pure lead for casting m/l bullets. It really helps fillout in my .54cal MaxiBall mould. If the tin doesn't work, the alloy is history for casting bullets.

If you have GC's for sale for reasonable prices, by all means post them next door at Reloaders Guide where we have a section specifically for finding a new home for that sort of thing. You will have to register there as you did here. I can always use .22, 6.5mm, .30, 8mm, & .35.

[kodiak1]

oldgreybeard
Welcome to the forum.

Ken.

[TheOldGreybeard]

Versifier, I am more confused than ever! (well, that may be a slight exageration...) The process of using sulfur to clean out excess zink is discusssed in Lead and lead alloys...
Is it your experience that this does not work?

[versifier]

It may take some of the zinc out, but not enough to make the alloy castable. I believe all the sulfur will do is flux your melt below 800*F. Never mind the stench it creates. I am no metalurgist, just had basic chemistry, but I do not believe that it is practicable in the low temperature range that we use for smelting. As I understand it, if you get hot enough to do it efficiently, you go above the vaporization point of lead and have that toxicity issue to deal with. Such temperatures are pretty much unobtainable with the turkey fryer/propane or Coleman stove setups most of us use to smelt with anyway, even if it works well in an industrial setting.

I may be wrong about this, but if so am more than willing to learn better if I have been misinformed. It sure would be a godsend to many of us if we could do it. Logic tells me however that if it were that simple, it would be a well known and often used technique, given the increasing amount of zinc WW's that we have to deal with. Search next door at Cast Boolits if you like, there have been dozens of threads about zinc and zinc contamination.

[carpetman]

I have serious doubts you have zinc contamination. Why? Melting point of zinc is 787.15F and lead is 621.43F. You would have zinc wheel weights floating on top of your melt and not melting unless you worked at it. Maybe there are those that can tear up a train track with a rubber mallet.