Been reading here for about a year...very knowledgeable folks, and I have learned more that I can describe. I thought I had a few concepts understood, but reading on the Nosler site has me a little confused. Any wisdom from the clan would be appreciated. The ballistics data for the 270 and 280 (not the AI), both shooting a 140gr AB. It lists the MV for the 270 at 2900 and the 280 at 3000. Why would the 280 be a fair amount faster, given that I think the 270 has a higher max chamber pressure in the SAAMI spec. I guess I had been assuming that they wouldn't be loaded to a different percentage of spec. Where is my understanding off (I assume Nosler doesn't have an error on their site)? Side note - my understanding is that the 280 spec pressure is lower due to being developed as a semi-auto and in bolt form the 280 should be able to handle pressures closer to the 270.