Composite tube assemblies comprising a composite tube comprising a distal end having a first conical section and a second conical section, wherein a distal end of the first conical section is in contact with a proximal end of the second conical section having the same outer diameter as the distal end of the first conical section, wherein a proximal end of the first conical section and a distal end of the second conical section have a smaller outer diameter than the distal end of the first conical section, a locking ring disposed around the first conical section, an end fitting disposed around the second conical section, wherein the end fitting is coupled to the locking ring, and a retaining ring circumferentially disposed around the locking ring are disclosed.