Well the 270- is a bit older as it was introduced in 1925 and the 280 was introduced in 1957. Being a fan of every caliber based on the 30-06 I will be the first to say that there is dern little if any difference in performance on game between the 270, 280 and 30-06. Not even a drastic difference to include the 25-06 and 6.5-06.

With the development of the Barnes TXS bullets, the difference becomes even less significant. Hit any NA big game animal well with a 150 grain TXS frooom the 270, the 160 TXS from the 280 and the 180 grain TXS from the 30-06 and you will have one very dead critter. Throw in the 338-06 and 35 Whelen too. All owe their existance to the 30-06 case. A very good family to come from.