From the Hodgdon Reloading site, duplicating the Win AA 26 gm. load is 5500 psi. I have used these in cold weather and have had a few bloopers, so I increased the powder charge to 13.1 grs of Win. AALite powder. this increased to 6900 psi and 1025 fps.
This is factory WinAA Lites-26 grams shot( 15/16 oz.) with 12.1 grs. Win. WAALite powder, Win 209 primer, Win WAA12L wad, velocity 970 and 5500 psi replicates Winchester Factory load.
My 302 1 oz. Mec bar averages .923 or very close to 15/16 oz (.9875). Mec # 19 bushing averags 12.1 grs of WinAALite powder.
I think you will like them for a factory shell. The cases are good for reloading, but not as good as the old AA.
Using Remington, either Remington Premiers, Nitros, or Gunclubs,
#19 bushing 1 oz shot WAALite 12.3 Rem. 209P Rem. TGT12
970 fps 5,800 psi.
Again this is from the Hodgdon site.
Winchester or any of the powder manufacturers will never tell you it is safe to shoot Damascus barreled guns, an insurance thing.