The Contender was meant to handle these loads. Your biggest problem will be accuracy in this barrel. I don't have this problem, because I have a .45 Colt barrel. The jump that the bullet has to make to get to the lands and groves in your barrel lead to the accuracy problem. As far as the heavy loads, that should be no problem.
Just remember that these loads should be kept separate from any Colt clone rounds. they are not meant to be shot from these guns. Way too much power!!! Also remember that the info on this or any wire should be verified first through researched from established reloading books before being used. Sometimes the info you get may be inaccurate and could be dangerous.
Hope this helps.