REWRITE!!!!!!!!!!!!!!!
Many people are under the mistaken belief that .22 rimfire handguns are far more accurate than their big bore brethren. These shooters this conclusion because they shoot more accurately with a rimfire. This is a natural conclusion, but an incorrect one. The larger handguns aren't less accurate, but the shooter often is because he psyches himself out.
Running an indoor range has certainly exposed me to the gamut of excuses that are used in an attempt to justify horrible technique. I don't know how many people come out of the range bay, walk up to me and say, "Your rental (Glock, S&W, Colt, Beretta, Sig, whatever) is not very accurate!" I then ask them if they have any ammo left. If they do, I go out, put out a fresh target at 25' and then put one shot right through the middle of the bullseye. That quiets them down... and then I spend a few minutes explaining how to properly hold the handgun, how to align the sights, and how to press the trigger. In five minutes the same shooter who was incensed at the inaccuracy of centerfire handguns has suddenly smacked the center of the bullseye. Now, his mouth suddenly hangs open in disbelief until he does it again, and again. It's great to see people like this really smile and enjoy the positive feedback that accurate shooting provides. And, it's really not all that hard to do contrary to popular belief.
One essential truism of shooting is that stress will magnify any flaws in your technique. While it is true that the only essential requirement for obtaining a precise hit is to have the sights perfectly aligned at the moment the gun fires, this oversimplification fails to clarify why good technique make accurate shooting easier. A good, solid grip on the handgun minimizes movement due both to recoil and the secondary effects of pressing the trigger. The proper method of pressing the trigger minimizes the chances of disturbing the handgun immediately before and during the moment of firing. Just as you can't construct a solid building on a shaky foundation, you can't turn yourself into a precision shooting machine if your foundations of grip and trigger press are flawed.
The proper grip eludes most shooters. While there are numerous excellent books on how to shoot a handgun which cover the proper grip in excruciating detail, I can vouch from my observations of hundreds of shooters a week that we as a nation have given up on reading and are indeed a nation of TV watchers. It's getting so I can identify a person's favorite action movie star by the way they hold their handgun. Those fans of violent action flicks and gritty inner city police dramas are entranced by the 'horizontal hold' where the handgun is canted 90º inward. Old cowboy movie aficionados like to shoot one-handed with their upper arm against their side, pointing more than aiming. Women especially seem to like the 'cup and saucer' hold, resting their gun hand on the palm of the off hand like Christie Love or Charlie's Angels. What have I learned from TV? That Hollywood in general has as much, or rather, as little expertise on the subject of firearms as they do on politics or the environment.
To compound the problems of a crummy grip, most shooters seem to think that the trigger is merely a big fulcrum that applies pressure to the base of the bullet. The harder they jerk the trigger, the faster that bullet will come 'shooting on out of there.' Or maybe they think they need to assist the handgun's recoil, as the Hollywood types do, for style points. Inexperienced people can't seem to understand that less can be better when it comes to pulling the trigger. Bad technique on the trigger is disguised when trigger pulls are short and light, but the rise in popularity of trigger-cocking pistols has certainly accentuated the problem. For instance, when I first bought a Glock, I swore at it for its inaccuracy. I couldn't hit a barn from inside with it (actually, I couldn't shoot a 6" group at 15' with it). What was the problem? It was me, of course. 'My Glock' now shoots consistent one-holers at 25' -- and so does yours or anyone elses' quality handgun.
How do you know if your technique is faulty? Lack of accuracy at close range during slow fire is a big giveaway. It is the rare gun indeed that won't shoot one-hole groups at 15' when fired offhand by a good shooter. The most common indication is when you constantly shoot low and perhaps to the left. Some shooters have adjusted their sights accordingly, and their symptoms will be the occasional shot high and to the right when they mistakenly forget to flinch and jerk. Of course, the best thing to do is to understand how to hold the handgun and how to press the trigger, and let the results speak for themselves.
The proper two-hand hold for a pistol is as follows: grasp the handgun with the gun hand so that the longitudinal axis of the bore exactly bisects the angle between thumb and forefinger. The gun should be grasped high enough so that the web of the hand is wedged up against the flaring backstrap (or grip safety, depending upon the gun) of the pistol, and the middle finger of the gun hand should be pressing against the bottom of the trigger guard (of course, the trigger finger is outside of the trigger guard until ready to shoot). The thumb of the gun hand is on the opposite side of the gun from the trigger finger, and is extended up at a slight angle from the vertical, as if you are giving the 'thumbs up' sign, resting against the slide (and perhaps on top of the frame-mounted thumb safety, depending upon the particular pistol). The gun hand holds the pistol firmly but not tightly, with the same amount of force used when holding a hammer or tennis racket, and squeezes the pistol grip from front to back. Now, take your off hand, extend its thumb up in the same manner as with the gun hand, and bring off hand to the gun so its thumb lies against the grip directly in front of that of the gun hand, also held vertically and against the slide. Both thumbs are now on the same side of the grip. Don't worry, the slide will not be retarded by your thumbs or injure them. Now, keeping the entire length of the thumb pressed against the area of the grip not covered by the gun hand, wrap the off hand around the gun so that the index finger lies underneath the trigger guard with the first joint directly under the trigger guard and the fingers touching. The off hand holds the gun hand and pistol firmly but not tightly, and squeezes the gun hand from left to right. Now that you have a proper grip on the pistol, recognize that it is virtually surrounded by your hands. This idea of 'placing as much hand on the gun as possible' lets you control the gun far easier and with far less effort.
To grasp a revolver properly, follow the instructions as above except that you will bring the thumb of the gun hand down over the middle finger, locking your grip on the gun. By the way, this is the same way you'd hold any handgun if you were shooting one-handed. Then, place your off hand so that its thumb is placed just behind the joint on the thumb and wrap your hand around as above. This hold will definitelylock your grip on a revolver, but it doesn't work nearly as well on pistols as the modification described in the preceding paragraph because of the differences in grip shape between the two designs.
Let's look at the proper technique for pressing the trigger. On double action guns, you want to maintain a steady and constant pressure without disturbing the sights, so that the gun goes off while you have the sights aligned. You can learn this by slowly pressing the trigger and forcing yourself to keep the sights aligned. A good trick is to have your shooting buddy load (or not load) your revolver or pistol and then you fire it. Since you don't know whether the gun will go 'click' or 'bang' any flinches or jerks will be woefully apparent. Single-action guns are far easier to master since they generally fire with less effort, meaning less disturbance will be transferred to the handgun. However, single-actions do not have a lock on accuracy and speed. You the shooter control that.
Now that you know how to squeeze the trigger and grip the handgun, what's next? How about practice? It is the rare shooter who will go out and spend a box of ammo trying to make each shot a bullseye at 15' and thus really learn how to accurately shoot a handgun. Think about it. If you can't put one shot thru the bullseye while taking your time, how are you ever going to put a bunch of shots on target quickly? The best drill you can possibly do when you go to the range is to load your revolver's cylinder, or place five rounds in your magazine, and then take your time and go for bullseyes at 15' with each and every shot.
Remember... hold the gun properly, align the sights, focus on the front sight, and press the trigger. If you're not sure you're doing this right, or you're not hitting the target, ask an experienced shooter. Better yet, find a qualified instructor and then take a lesson! You'll certainly have fun, and who knows? You just might learn something.