I played paintball for the first time this past weekend. I played from about 9 AM, to 3 PM, and I learned several lessons about gun fighting in general. Please tell me if you agree or disagree. A) Close "Combat" is very physically demanding from an aerobic standpoint. Unless you're used to running, sprinting, squatting, and moving continuously for several minutes at a time, you will be at a disadvantage in a real gunfight or shootout. (I played mostly on small fields, like Speedball) B) Weight of your gear and gun are key. I was using a rental gun, which weighed more than most of the premium guns. Repeatedly shouldering this gun, and carrying it and running with it for 5 hours got tiring. Even a gun that was several pounds lighter would have been considerably easier to use. (The gun was not heavy, but shouldering and moving it hundreds of times became fatiguing.) C) Weapon accuracy is important. My rental gun was clearly not as accurate as many of the high end guns other players were using. My paint at 20-30 yards was hitting in a wide radius, whereas other players were able to focus in on me at the same distance. In a real shootout, only a small portion of the enemy may be exposed, so accuracy differences between guns become more important. You may expend many more valuable rounds with an inaccurate gun trying to hit a small, yet visible, target. D) For a real life "skirmish", you need to carry more ammunition than you think. I went through about 200 balls (rounds) the last 10-minute game I played. I wasn't wasteful, I was simply using aimed fire to keep the enemy pinned down, and to give my teammates cover. I went through roughly 200 rounds in about 10 minutes. In fact, I think the more ammo you can use, the better your chances would be for survival. A high volume of fire is useful for keeping the enemy at bay, and keeping you alive. D) Iron sights are difficult to use in stressful/fast-paced situations. When you're moving, and trying to shoot at other moving targets who are shooting back, there is precious little time to try to use iron sights on a gun. You need to be able to use some other alternative sighting method. If you pop up from above cover, you need to be able to acquire targets quickly. I think some easy-to-see optics would be advantageous, like an Aimpoint. Conclusions. All of this made me realize that in real life you'd probably want a very light weight, accurate gun, with some sort of optic sight designed for fast target-acquisition. You'd want to be able to move easily, quickly, and be able to carry a large amount of rounds. Thus, an AR15 with a fighting optic seems like an ideal combat setup. I imagined running around with one of my heavy AK47s with iron sights, mediocre accuracy, and 300 rounds of 7.62 ammo, vs. a lightweight M4 clone with an Aimpoint, with 300 rounds of 5.56 ammo. Given my experiences from paintball, the M4 seems like it would be considerably easier to use in a shoot out. I imagine the AK would seem like a heavy and less than accurate "rental" gun. Edit: Please let know if you believe these impressions are valid. I've never been in combat, and this is the first day of actual paintball games I've played.