Will be loading 270 grain barnes lrx in hornady cases..I previously loaded RE 15.. I want to try this as its supposedly between RE15 and big game.. thanks...
I tested 15.5 in my 20BRAI that I've used 15 in. 15.5 was just a slight touch slower than 15.
I think if you backed off from your RL15 load and worked up you will be fine, all else fails call Alliant.