ORIGINAL: Retaks
I dont know how true this is but i was told that you are only saposed to load a tracer round every 3 or 4 rounds. It was because the buring flame will heat the barrle up alot more quickly then a regular bullet and they foul the barel up alot more. I dont know how true this is and if you only shooting a shot every once and a whyle i dont see a problem.
Thats typically for fully automatic weapons.