It would seem that there are different "poly" coated bullets.
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Yeah there sure are!! Two main types, the Hi-Tek type and powder coated. The Hy-Tek is a two part coating that usually involves to coats of the "paint" to cover the bare lead boolit. Then it is sized to it's final dimension. (I do not use this product, so I's unsure just how it's applied).
Powder coating is what I use, as a home applied coating. My starting method was tumble coating using harbor freight red, which is a powdered epoxy paint. It is applied by shaking the bare lead boolits with air soft BB's in a plastic bowl. Then baking for 20 mins at 400 degrees. I graduated to the harbor freight electrostatic air sprayer, this gave a better coverage, prettier boolits. Then I started use powder from "powder buy the pound". It's powder poly paint, it's a much higher quality than the HF stuff. I want to get some PC from a guy on the cast boolits forum,"smoke" is his handle.
In my experience the PC method is far superior to plain lead boolits, lubed and sized with some sort of grease. Some say it's more labor intense than plain lead and lubed boolits. I say it's about the same time expended. Only shorter time expended is a tumble lube type Lee boolit that is NOT sized. PC boolits have to be sized before use just like lubed lead. The oven curing is the only extra step, and it only takes a couple of hours for 500 boolits.
Performance is the main point. I can run as many PC boolits as I want to through several pistols, the barrels are slick and clean, only require a wet patch with your favorite solvent to get the powder fouling out. NO LEADING! Accuracy is excellent as well, as good as or better than plain lead, plated, or jacketed bullets.