All you net lawyers, give it a rest.
I have about 200 pulled US .308 tracer bullets. I shoot them in my .30/30 Marlin (single load), in all kinds of .308's and .30/06's. I used standard loadings for the bullet weight and they light just fine. No damage to any firearm.
They are capable of starting fires under ideal conditions so be mindful of the impact area.
When seated to factory OAL they feed and cycle perfectly through my Remington Woodsmaster 742 carbine in .308.
Shot one at an informal 500 yard match through my Model 70 .308 F class Palma rifle and didn't tell my spotter. He was watching through a 20X spotting scope. "What in the hell was that?" came the question from his incredulous face. I laughed 'til I thought I would pee myself. They are very much visible even during the brightest part of the day.