I've found that the standard lube-grooved designs are more accurate overall than the tumble-lube versions, using both powder coating and not using it. But if you already have the tumble lube versions, they powder-coat just fine too. I prefer RNFP for how they feed in semi-autos, but some guns feed truncated cones better. Mine don't. The Lee 158 .358" FN with the single lube groove and bevel base is an excellent bullet, and I load it in various guns from 9mm and 357 Mag to 357 Herrett and 35 Whelen. The Lee 175 40 cal single lube groove design shoots very well but sometimes hiccups in feeding. I don't like any of the Lee 44 cal 240 gr designs.
If you melt clip-on wheel weight while paying attention and monitoring, the lead alloy ones will dissolve completely before the zinc ones begin to melt. I sort them well beforehand, but inevitably, I miss one or two zinc weights, and they just scoop right out whole. The alloy takes on entirely different casting characteristics with just a tiny bit of zinc added. You'll know if you screwed it up, particularly with tumble-lube designs, as the groove won't fill out.
Yes, 70-72% lead alloy is monotype, with about 9-10% tin and 18-20% antimony. You won't need to add much to your wheel weight alloy to harden it significantly. I have experimented a lot with alloy composition and I recommend doing that.
