I've had pretty good success with this one from Caldwell. Just mount it up on a tripod and if you position it right it pretty much always either catches it or drops it right below the tripod. It also doubles really well to sit on the bench right beside your AR and keep the next guy down from getting covered in hot brass.

https://www.amazon.com/dp/B00EB5OU06?ref=ppx_pop_mob_ap_share