Thats how I use to train when I was in school we would play airsoft we had this stretch of land that ran about 5 miles (public) and we would work on things from tracking to map reading and tactics. There was a few old buildings there and we got permission to use them and we even played a couple of games with the local SRT it was all good fun until you get put down by a LEO that out weights you by 100 pounds. But it was all good fun and good training, the only problem I always had with a airsoft gun was I had a classic army full legnth m16 style rifle set up like a SPR.
I would sit there see someone and try to take the shot and it come no where near hitting them. I kept forgetting I was shooting an airsoft gun and that I didn't have the nice long range ability. But for running drills and all that can't get go wrong.
"come on you sons of b***hs! do you want to live forever?" Sergeant Daniel Daly, USMC, Belleau Wood France June 6th 1918
"You can be as mad as a mad dog at the way things went. You could swear, curse the fates, but when it comes to the end, you have to let go" Benjamin Button