I bet it will work with 130's as well. I say that because i used RL25 a few years back running similar tests with 130's in the 270. From the 22" barrel of a M70 Classic I was getting 3200 fps with no issues I could see. I used the Barnes Manual listed max of 65 gr and the "blue" Barnes bullet.
My understanding is that RL26 is the newer rendition of RL25 without the temp sensitivity.
A 150 gr 7mm bullet at over 3050 fps. Isn't that a 280 AI?