It is pretty stable. I used it in below freezing and upwards of 110 degrees with no visible difference. I used some US 869 and it is really temp sensitive. Loads shot in temps up to 80 degrees were good, but above that it really gets bad. That is why I went to Norma 217. I lose about 75 ft/second on velocity but the difference in accuracy is amazing. The max in my two 6.5-300s is 85.7grs of 869 at 3350, and Norma 217 at 74.1grains is 3277 both with 130gr Swift Sirocco II. The groups with 869 are 0,8 inches, with 217 0.3inches.