Piney Mountain 22LR tracers have some considerable differences when compared to most tracers. Piney Mountain tracers are hollowed out in the back and the tracer element is inside the bullet. 

When fired at night, these 22LR tracers are visible from the rear but only visible from the front once the tracer reaches a 45 degree angle. Since these 22LR tracers are hollowed in the back, the tracer element never makes contact with the barrel; they are clean and not corrosive. 

The green 22LR tracers are slightly brighter than the red and both are brighter than 5.56 tracers.