[Jason M]

Interesting because I was under the impression that ball screw support bearings where a whole different series enhanced to handle thrust loads. At least the bearings I've seen marketed as ball screw supports where designed with a different contact angle and hefty races.

Depends on what you mean by "different series" of course but I think I know what you mean (referring to 7XXX series?) and if so you're right on both counts. The term "angular contact" carries heavy connotations of the 7XXX series but it's used as a design term more than for one particular series (by me at least), in general meaning "not purely thrust or radial". Most common in the 7XXX series of angular contacts are 40 degree contact angles (72/73XX series) with 15 and 25 degrees in the super precision (more commonly light/ultra-light 7XXX(X)) but you'll find angular contacts in other series from 8 to 45 degrees that I'm familiar with, the range may in fact be wider.

We were not talking about self-aligning Bearings, but when you put the 5300 number in there, these come in that series

I wasn't aware of that, never run across it, what manufacturer uses 5XXX for self-aligning ball bearings? Every manufacturer I'm familiar with uses the 53XX and 52XX series numbering for double row angular contact ball bearings. I don't have a lot of experience with self-aligning ball bearings but I thought I recalled the SKF nomenclature being 1XXX and 2XXX

Apologies to the original poster for the tangent