I found the SAAMI has approved the 500 A-square. I was surprised not to be able to find 500Jef or 505Gibbs at SAAMI. I do see both of those at the CIP site, but; no A square. That could be my error at either site. And, I am still unable to access the drawings at the CIP site.

This link will show the 500A2 and you can [return to table contents] for other drawings:

http://www.saami.org/PubResources/CC_Drawings/Rifle/500%20A-Square.pdf