My very first day ever airsofting in any organized fashion was in my friend's backyard, with most everybody running springers and little gas pistols except for me, with a mid-range AEG, and another guy with a brand-new UTG L96. At one point, I poked my head around a corner at just the wrong time and got hit in the face by a round from the sniper. The yard was small enough, and the gun new enough that the round broke the skin and stuck to the tip of my uncovered nose, which proceeded to bleed for a decent amount of time. I have a fairly noticeably scar to this day.
We also got a lot of tackweed/tumbleweed related scratches where we play, which are irritating but not particularly dangerous, and are completely avoidable if you wear the right gear.
Our team was pretty smart and usually fairly careful, makes for some bland stories... It's all the teenage kids we skirmed with that did stupid stuff, like get their teeth shot out, etc...