I never had a Walker but I had a dragoon. I've fired 50 grains out of it before so with the extra length of the Walker cylinder I have no doubt it ill hold 60 grains. I guess it boils down to what you consider a handful. I know 50 grains out of a 4 pound gun is tame. I don't see 60 grains out of a 4 1/2 pound gun as being much different. 100 grains out of a 2 pound pistol might be a handful.
Compared to a hot .44 magnum, it's nothing. The weight of a Walker absorbs most of the recoil.