Couldn't find a brass catcher than worked for an AR10 rifle or wasn't overpriced so I designed my own.
https://i.imgur.com/EoEm0Tp.jpeg
https://i.imgur.com/xYQ9uva.jpeg

It uses 3D printed clips that snap onto the pic rail. The clips hold an 1/8" steel rod which supports the mesh bag. Right now it is mild steel but I'd like to order a section of spring steel in the future.

The mesh bag was a cheap fishing net I found at the local hardware store. Added a paracord to cinch the bag closed and it is fairly simple but it seems to work. I'll be taking it to the range this week to confirm function and find any bugs. The 3D printed clips should be up on thingiverse soon.

https://www.thingiverse.com/thing:5478053

The Caldwell one with the velcro strap has always worked fine for me on my ar10.  The pic rail version works better for my ar15s.