At a recent event, one of the competitors had a brass deflector which directed the ejected cases downward.  Does anyone know a source for this product.  Also is it DCM legal?

Sinclair International sells one that is CMP legal. It costs about $20 and some I have talked to are lukewarm on it. As for brass ejecting from the AR, there are several ways to get it to eject less vigorously and keep it close. Adding RTV sealant to the built in shell deflector and trimming the ejector spring are easy to do and will accomplish the same thing. Sometimes the brass will eject but hit the deflector and jam up the rifle, at least that is what a couple of guys told me theirs did.

[url]sinclairintl.com[/url]

Different subject, but whatever happened to ejection forward of the gun? The A2's seemed to always bounce brass off the deflector and forward of the rifle  (at about a 30 degree angle) now the cases from most of the A3 uppers I've shot are ejected rearward at a 40 degree angle. (doesn't that defeat the purpose of the brass deflector?)

Those cases ejecting to the rear are much more likely to hit lefties and people walking on the line.

I use a deflector shooting across the course.
What I have noticed is that it works well on rapid fire, but in slow fire the shell casing often hits the deflector and bounces back in the chamber. You have to flop the rifle over 90 degrees and dump out the empty.
Having the brass in one pile is worth it.
I've shot a lot of matches and never has anyone raised a rules objection.

There is a specific shell deflector (clip on) that is CMP and NRA service rifle legal. The one Sinclair sells is one.