A method of making a crimp connection comprises sliding a crimp ring over a female end of a pipe or tube, the crimp ring having an oval shape; inserting a male end of a fitting into the female end of the pipe or tube; sliding the crimp ring toward the fitting such that the crimp ring at least partly overlaps the inserted male end of the fitting; and applying a compressive force to an exterior surface of the crimp ring. Prior to applying the compressive force, the crimp ring has a first inner diameter and a second inner diameter transverse to the first inner diameter. The first inner diameter is greater than the second inner diameter. The first inner diameter is greater than an outer diameter of the pipe or tube. The second inner diameter is less than the outer diameter of the pipe or tube.