Where to Use 'Em?
Shooting rifle tracers at 100 yards is not as satisfying as I had envisioned. The bullet moves so fast, it's just a flash of light that's gone in a second. Unless, of course, it ricochets off your backstop (the one you thought "absorbed" the bullets) and flys up and into the next ZIP code.
Pistol rounds have lower velocity and much wider base with more burning material exposed, so they're fun at 50 yards or more. But I think 300 yards of distance is the minimum range to really enjoy seeing the rifle bullets fly.
Now, where can you shoot long ranges with a good backstop where there is little or no fire hazard? Not many places. I shot most of my tracers in a rock quarry and a sand pit, with huge piles of crushed stone and sand as backstops. And a lot more rounds bounced off them than I'd expected.