Over in this thread there’s some question about whether it’s realistic that FPS games often allow you to shoot while running with little or no accuracy penalty. I don’t know much about it, but it seems that your accuracy would be a hell of a lot worse if you were running around, weapon bouncing, trying not to run into things. Are there any hard numbers on this sort of thing?
I imagine it depends on the gun – a pistol is hard enough to aim at a distance just standing still, whereas a shotgun wouldn’t matter much due to the spread, as long as the target is reasonably close.
But hey, there are some realistic/semi realistic PC games. None can be as bad as Counter-Strike 1.6, where running can cause your gun’s bullets to exit perpendicular to the barrel and hit the ceiling/floor!
Try Operation Flashpoint for a game that I imagine represents gunfire better than most.
You have to aim for deflection, running screws up your aim, running gets you out of breath, I might fire it up again if I get time. There’s a term for gunfire like that which escapes me at the moment, most older games use the shoot and instantly hit your target routine.
The spread of a shotgun is around one inch per yard, so you can figure at 18 feet to have a pattern around 6 inches in diameter, and at 50 feet less than a foot and a half. This ain’t the movies, folks. A shotgun does not create a wall of death.
The spread of a round of shot fired from a shotgun is a lot less than most people expect; for a cylinder choke it’s roughly 1" per yard of distance to target, so at an effective range of 25 yards you’re only getting ~2 feet of spread, or about 1.5° of overall arc. Do you think you can point-shoot a target at 25 yards within 1.5°? Or even at 25 feet? It’s an urban legand that shotguns are easier to use because “you don’t have to aim them”, though the virtue of being a longarm and a very powerful one at that makes them useful for home defense.
As far as shooting while running with a pistol, despite what you see Bruce Willis doing in the movies, it’s essentially impossible to keep a steady sight picture, and even with a shoulder weapon you can’t hold it still enough (nor can you run at full speed while contorted in rifleman position) to maintain a sight picture at all. Elite law enforcement and military units sometimes teach fire while during slow, steady movement (a walking pace) but even this is difficult. The recoil from firing an automatic weapon–even a poodle shooter like an M4–is also going to literally put you off your stride, which is why you see soldiers and special tactics guys hug down near cover, brace feet and if possible the leading arm, and snug the gun up against a shoulder before firing.
You might let off covering fire while moving, I suppose, but this is unaimed and it’s pure chance to hit anything, and not likely to be effective against experienced pros who will realize that you pose minimal risk to them. This is why professionals move in cover formations, where one man or team provides cover fire for the movement of another.
In short, don’t rely on Hollywood or Electronic Arts to give you an accurate portrayal of firearm handling and marksmanship.
Stranger
If you want realism in your shooting, try America’s Army 2.0 . The running and shooting was a bit of a challenge, but that was because I was bored and sniping the players in my BNCOC class not paying attention. 
SSG Schwartz
Not a PC or video game, but I shoot International Defensive Pistol Association (IDPA) competition and we regularly shoot on the move. Not running full out, but at a trot or fast walk. Sometimes advancing or retreating, sometimes moving sideways. Targets are usually 10 yards or closer. Sometimes they are inside three yards distance.
It’s not as difficult as I’d thought it would be to get a decent score. The “zero down” area of the target is a circle about 10" in diameter.
There are several other pistol shooting games such as IPSC that also require shooting on the move.
You’re shooting at stationary targets, at known locations in (generally) full sunlight and with no one shooting back. IPSC-type courses are fun, and you can certainly develop some useful skills on them, but they’re nothing like real combat.
Stranger
Some are movers, but not too many as they are a pain to set up.
I do agree that it’s not like real combat though. And I hope you’re not saying that a video game is.
What, you don’t get powerups and stimpacks in real combat? 
Nah, video games are nothing like combat. Except for Tetris. That’s exactly like being under fire.
Stranger
I designed the targeting mechanic for Rainbow Six, one of the first realistic tactical shooters. One of the big innonvations with Rainbow Six was degrading your shot accuracy based on your movement speed.
In the real world you can certainly move steadily and fire accurately. I’ve watched special forces soldiers hit targets with pinpoint accuracy while moving at a fast walk.
The place where most videogames fall down is letting the player fire accurately while running or jumping. If you’re moving too fast to maintain a stable firing platform your aim goes all to hell.
I was tought to shoot while running; however, only when charging, only semi-auto… and not to expect to hit anyting.
Used to practice it out in the strip pits when I was young and foolish. When you have water or dust to see where your bullets are striking, you can do a pretty good job with an semi-auto .22.
I never snapped on why ‘tetris’ made me sweat so much until I read this thread. It is exactly so… LOL
So, Tetris almost makes it to the list of most realistic action films?
If I ever design an FPS, I’m totally ripping off your work. Uh, I mean using it as inspiration. That was one of the first shooters I actually liked.
Thanks. It’s already been ripped off all over the place though … .
In the first R6 we didn’t even allow the player to jump. We interviewed some hostage rescue expert about the tactics they used during an assault. They were adamant about maintaining a stable firing stance at all times, even if it meant detouring around obstacles you could easily vault over.
We also didn’t include knives for a similar reason. We asked our experts about the standard movie technique of silently slitting a guard’s throat. Their response was that it was actually quieter to shoot the target in the head with a silenced pistol. Throat-slitting resulted in a lot of gurgling and thrashing around. I’m not sure if this answer came from training or field experience … .
I’ve never cut anyone’s throat, but I’ve seen a few animals dispatched by this technique (hunting/amateur butchery) and it is surprisingly noisy, and not at all instantaneous. The professional texts seem to recommend putting the knife through the unprotected base of the skull or above the C6 vertebrae (trying to sever arteries of the heart or kidney from the rear is tricky at best, and while a lung or liver puncture is very likely to be fatal it won’t be quick or quiet) but if I were for some bizarre reason in the position of needing to dispatch a sentry–say, if I’m called upon to disarm the guns of Navarone–and I have the choice between contact distance with a knife and close standoff with a silenced pistol, I’ll take the pistol.
One of the reason that professionals are trained not to jump or vault is not only because of needing to maintain a solid shooting stance (although that is true as well) but due to the hazard of jumping around in a cluttered environment. If you twist an angle or break your hip in a simple fall, which is suprisingly easy to do, then you’ve not only put yourself but your entire team at risk, both because now there’s an open hole in your ranks and because they presumably feel obligated to rescue you. That parkour/freerunning stuff looks awesome in the films, but in reality, without preparation and choeography you’re likely to get seriously hurt.
Stranger
Playing paintball can give you an idea of actual combat conditions. I would say that if you’re shooting while running, it’s generally just supressive fire, or if you aim more carefully you’re going to run into a tree. You can either concentrate on where you’re shooting or where you’re moving, not both.
I can fire a paintball gun accurately while walking quickly. It requires a speedball-type field with reliably flat ground and I like to be moving towards the target (more or less). However, walking at a steady clip and firing usually means you have no cover.
Running and firing is, as you say, cover fire at best, but I have hit people doing it.
If you don’t want to try paintball, get a laser pointer. Just try running around while aiming it at one spot on the wall.