Were the old model Vaquero 44 built on the Blackhawk Frame, if so they should hold up to full power 44 magnum loads shouldn't they, I know where one is at made in 1994, just wondering how it would handle 44 magnums and if it would be a handful to shoot.
Well, strictly speaking all Vaqueros are New Models, they have 2 pins rather than 3 screws. But yes, it should be safe with any standard factory loaded 44 Mag round. The shape of the handle allows the gun to roll in the hand lessening felt recoil but it is up to each individual whether or not they can handle the recoil. It will be fairly stout with full bore loads.
In 2005 Ruger did change to a smaller frame to bring the size more in line to the original Colt SSA design.
I have two .45 colt vaquero's. One is the 'original' large frame model and the other is the New Vaquero on the smaller frame. I also have two Super Blackhawk's, one in .44 magnum and one of the new five shot Bisley's in .454 casull. The larger vaquero that was offered in .44 magnum was built on the same size frame as the Super Blackhawk and is plenty strong to handle just about anything you would want to shoot through it. Ruger single action revolvers are my favorite guns.