1. How do you know the difference between wheelweights with zinc and those without?
Zinc wheel weights when dropped on a concrete floor have a definite ring to them where as lead will just have a clunk sound. Most wheel weights with the clip attached outside the body are zinc, looks like they are riveted on and a lot of zinc weights will have Zn stamped on them, but not always. A pair of wire cutters will cut into lead easily but zinc is hard as a rock.
2. How can you get rid of the zinc? I've read something about the lead melting sooner than the zinc but the temp difference not being much. Does that mean you need a thermometer to keep it in the right spot?
Lead melts at 327 degrees and zinc at 419 degrees. I use a large cast iron pot and a turkey fryer to smelt my weights, As soon as the lead starts to puddle I adjust the heat to maintain that condition. As long as the melted lead temperature is held below 700 degrees all the zinc weights will float to the top along with the clips and I just skim them off. Surprisingly I found a few stick on wheel weights that floated up also.
3.What is best to flux the mix in the pot?
Only fluxing I do when smelting is to stir with a wooden stick. The ash of the wood stick will act as a flux. I stir a lot to keep the mix from separating until I'm read to pour into ingots.
4. If I waterquench straight wheelweights can I expect any expansion at 1600-1700fps without annealing the bullet nose? Do I even need to waterquench at that velocity anyway? I have a Ranch Dog mould that drops three plainbase and three for a gas check.
Water dropped bullets will have a hardness of 19-20 BHN and I doubt you'll get any expansion at those speeds. I have RD's 35 caliber and 45 caliber molds and I cast them as air cooled which gives me a 12-13 BHN with a little tin added to the mix. Of course mine are gas checked as he didn't offer the plain base setup until after I had bought mine. I run the 35 caliber at 1900 fps plus in the 357 max (rifle) and the 45 caliber just above 1700 fps (rifle) and have not seen any expansion unless bone is hit. So to answer your question directly, at 1600-1700 fps water dropping is not necessary. If you are going to push them to the max like RD does then you may want to water drop them as RD's load tables are using water quenched bullets because he runs everything at max.
The real trick to shooting lead cast bullets for accuracy and no bore leading, as I'm sure you already know, is bullet to bore size. Make sure you're .002 or more over bore diameter. My 35 caliber bullets are sized at .3585 because that is the largest size sizer Lee offers. Ditto for the 45 caliber which is .454. I need to order some of RD's sizer's especially cut for his bullets because they are a little larger. With your mold and the plain base option you have I would try shooting as dropped from the mold first and I suspect you'll discover sizing those bullets is not necessary. I have a Lee plain base 158 grain mold that drops at .360 and I shoot these at that size and they work great. I've run these up to almost 1600 fps with no leading of the barrel at all. Didn't mean to get long winded here but hope this helps........
