A max charge of W296, H110, 2400 or H4227 is a max load, doesn't matter what kind of firearm it's fired out of.
I have a number of books that have different max loads for different firearms like these 44 magloads that are the same other than rifle, pistol, contender only loadings.
Couple things worth noting in them though.
The 265gn @1.610” load with H110, specifically.
Pistol max of 23.4 gives 1400
Rifle max of 22.2 gives 1700
TC max of 22.3 gives 1550
So the rifle and TC only loads are actually lower max loads than the pistol loads, maybe they were using a revolver with an exceptionally large cylinder gap, bleeding off pressure that otherwise showed signs in the other two?
Who knows, they also have different charges with 296 & H110 despite them being the same powder in different cans.
Then you have other data like the 2400 loads for the same bullet.
Pistol max of 18.7 gives 1300
Rifle max of 20.4 gives 1600
TC max of 20.4 gives 1450
Opposite results, that don’t support the above theory. Lots of factors go into testing environmental, consistency in components and unless using precise instruments results can be subjective too.
These are reasons I don’t blindly follow book loads and reference a number of sources before I pick a starting load.