A minor note about a mis-positioned &.
The model isn't F&N 509, it's FN 509. And it's not Fabrique
and Nationale collaborating, again -- Fabrique Nationale has been a single firm for many years and part of the Herstal Group. It's Fabrique Nationale - Herstal (also called FNH).
Hertal is a municipality in Belgium, and that region's government OWNS the Herstal Group. The Herstal Group, which owns FN, also owns Winchester and Browning and has a corporate relationship with Miroku in Japan. Hiroku builds shotguns for Browning, and builds licensed copy of Winchester rifles. (I've never been able to find out just how the company is run or makes decisions, but it seems to be an interesting mix of government and business.)
J.M. Browning did a lot of work for FN right up until his death (in Liege Belgium) in 1926. JMB started the design work for the FN Hi-Power, but it wasn't really finished until almost 10 years after his death. The BHP's original design was a striker-fired single stack gun, but the overall design was greatly changed over the decade after JMB's death.
Because of the time lapse, FN was able to incorporate some expired Colt patents that Browning had developed for that company. Some of the final design used was Browning's work, but not stuff originally intended for the BHP design. People give him credit for the BHP, but it's arguably more the work of D. Sauve, who worked with JMB at FN in Belgium, and later became FN's chief designer. Because JMB was so highly regarded in Europe FN continued to use JMB's name and designs.
FN-Herstal is an impressive company and offers impressive products. They build some of the most widely-used and highly regarded automatic weapons in NATO; a lot of them are used by the U.S. military, too!