I've used 4 of the Ramshot rifle powders for a couple of years now. I've no complaints about them. Don't have a chronograph, so can't make a good comment about temp sensitivety, but not noticed anything to suggest it is. Find Ramshot to be a clean burning powder and meters great since their TAC, Hunter, Big Game and Magnum powders are all spherical type powders. Have used one or more of these powders to reload 223, 257R, 25-06, 6.5x257R, 6.5x55, 270win, 7x57, 7mm-08, 300 Savage, 308win, 30-06. Never a problem using just standard primers with Ramshot. Don't reload any large case cartridges that would need a magnum type primer.