Ok so what i have learned from doing as much research as possible, the biggest difference that i have found between the use of large rifle primers and large magnum rifle primers is that under cold temperatures, the large primers might not ignite the powder as well. so i guess my question is does anyone know what temp the primers start having the weather effect them? i was given a ton of large rifle primers and would prefer to be able to use them now to reload since i cant find any magnum primers anywhere.