Step 1. The Pulsar Thermion thermal scope is designed for easy, “one-shot” zeroing or. Sighting in your rifle makes your point of impact (POI) match your point. of aim (AP) so your rifle is accurate. Read more. sighting-in. How to Sight In Thermion. Like the Trail, the Thermion is notable for many reasons but most importantly Pulsar offers an industry leading feature set - 640x480 sensor resolution with shuttered NUC, on-board recording, picture in picture, one shot zero, rechargeable batteries, and much much more. The Pulsar Thermion XP50 is an upgraded and physically redesigned successor to the Pulsar Trail line of thermal rifle scopes. Amazon.com : Pulsar Thermion XP50 1.9-15x42 Thermal Riflescope : ... 13 variable electronic reticles and one shot zeroing with freeze function ... Like my Trail XP50, the Thermion XP50 will not hold a Zero. Sight it in only to find later that it move 4"-12". Mount the Thermion on your rifle, and set your rifle on a …