I see Vic, hadn't looked that closely. How thick is your steel angle and are you planning to prepare the edge in any way? The side load will translate into a vertical and horizontal force due to the shape of the vbearing. If they are rated for 1700N axially then I would have thought that was fine - I suspect the bearings would force the rails towards each other (or the studs apart) and pop-off the rails long before the bearing gave up!