Brian48 you must be kidding..? You pulled that fouling from 200 rounds? That looks like what I pulled from my Taurus 94 22LR (used) which I assumed was horribly abused. I pulled literally pinky-nail sized flakes of lead from it. Maybe the prev owner just shot too much Remington through it. After my experiences and this thread, Remington is on my long-term S* list.
Shoot smart. Shoot S-Mart.