"Within a couple of years it (NyClad) became notorious (in the anti-gun media) as "cop killer" bullets because the nylon coating was believed to be capable of penetrating commonly used Kevlar body armor."


I believe the same. The (initially) green Teflon-coated Kennertium core bullet KTW metal piercing ammunition (the Teflon actually did nothing to enhance penetration, it was just there for visual identification) was always labeled as "Cop Killer" by the news media. Despite the fact that no cops were ever known to have been shot with it, let alone killed. And it was sold only to LE agencies for LE use. Later the bullet was made of uncoated solid brass. As it turned out, most LE agencies came to believe that metal-piercing ammunition wasn't really needed nor desirable (due to overpenetration), and KTW as a company died from lack of sales (probably assisted by its unfair "Cop Killer Bullet" reputation). I did some tests of KTW bullets and ammunition (the early design) on various types of steel plates back at that time. It was indeed very effective in performing as advertised. I even loaded some of the bullets in .35 Remington to fire in a rifle (all I had were .357 bullets). Now that combination was Really effective, I remember it punched straight through a 3/4" mild steel plate.