2nd what Alpo stated, a 8 x 12 tarp works pretty darn well. Having someone that can spot the ejection path for you is helpful too; I once played a sick joke on my kids. I had 100rnds of 45 that I was going to shoot; I told them if they both found 50, that I'd give them $5 each. I managed to strip off a few unfired rounds out into my hand when loading a new magazine......They both came up short
I took'em both out to Sonic for icecream afterwards and still gave them the $5.
The range that I shoot at has a concrete pad. I usually have to sweep all the rocks and .22's outa the way, but most fired cases are readily spotted. I can usually get 98-100% if nobody else is around. I used to be able to get 110%+ of what I fired, but lately the range has been picked clean. I haven't scrounged any 45acp, 45LC or 44's in a long while.
What are you gonna do, talk the alien to death? -- (on Sigourney Weaver's worry about Guns in Aliens)
"Safety is something that happens between your ears, not something you hold in your hands."
"I carry a small gun to compensate for my huge Blue press."