I am working on my first rifle build. I have the parts together for a 243 Win on a model 12 action. I have another 243 that doesn't see a whole lot of action, but I plan to make this one my "go to" rifle and hope to shoot it a lot with different weight bullets. I've been reloading for 25 years, but never considered that maybe a cooler powder might reduce the temperature of the barrel. I read something on the internet that said that some folks are using very slow powders that burn cooler. Its on the internet, so it has to be true. Have any of you experimented with loads that might extend the life of your barrel?