They are made IIRC for bullets travelling in the 1800-1900fps range. They base that 150 charge on 3 pellets which is not 150gr loose powder. 100gr BH209 will get most 250 and 300gr bullets up to the speed where the reticles will work. You really just have to try it to see how close the reticle is off at 150-200-250yds.