Some loads I have seen from other sources on the internet rival what I get with my 6.5-280 AI; Here is some pressure tested data from Hogdon:
140 GR. SPR GS-SP
Starting Loads -Maximum Loads. Brass-Win. Primer-Fed 210 Barrel 24"
Manufacturer-Hodgdon, Powder- H1000, Bullet Diam.- .264", C.O.L.-3.200"
grs: 49.0 vel.-2,570 pressure-52,900 PSI
53.5C 2,761 62,600 PSI
Manufacturer-IMR, Powder IMR 7828 SSC --------------------, C.O.L.-3.200"
45.0 2,482 48,600 PSI
50.5 2,766 62,000 PSI IMR IMR 4955 -------------------------------------- 3.200"
43.4 2,498 53,800 PSI
47.7 2,703 63,400 PSI Winchester Supreme 780 ----------------------------------3.200"
48.6 2,669 54,600 PSI
51.7 2,801 61,300 PSI
Hodgdon H4831 ------------------------------------------3.200"
45.0 2,542 52,300 PSI
49.5 2,731 62,300 PSI
Hodgdon Hybrid 100V -----------------------------------3.200"
45.0 2,635 48,900 PSI
49.0 2,848 61,600 PSI
IMR IMR 4831 -------------------------------------3.200"
43.0 2,532 49,500 PSI
47.8 2,772 62,300 PSI
Hodgdon H4350 -----------------------------------------3.200"
42.0 2,558 52,400 PSI
45.5 2,737 62,700 PSI
IMR IMR 4451 -------------------------------------3.200"
41.2 2,432 51,400 PSI
46.0 2,652 62,800 PSI
IMR IMR 4350 ------------------------------------3.200"
42.0 2,521 51,000 PSI
46.8 2,742 62,300 PSI