Alaskan is 45 ounces.
RugerŽ Super Redhawk AlaskanŽ Double-Action Revolver Model 5303
The S&W 3" N-frame is 39 1/2.
Model 629 Deluxe | Smith & Wesson
The Redhawk cylinder is 3/32" larger in diameter, but the guns are pretty comparable in size.
Both are odd looking to me. I like the look of the barrel being longer than the ejector. 4" would get my vote.