For a while after I got my Glock 17, I was shooting consistently about 2 inches to the left at 7 yards, with a decently small group. I had never had this problem with any other gun, including an XD, M&P, 1911, and SIG.
Q: Is it the sights?
A: Probably not. A right hander shooting left is a common issue with all handguns, but especially Glocks. And if you're noticeably off, like 2 inches at 7 yards, that's equivalent to about 8 or 9 inches at 25 yards. If the sights more or less look centered, there's no way you would be off that much. To check, shoot from a sandbag rest if possible. Also, shoot left handed and see if you now start shooting to the right.
Q: Should I drift my rear sight right to compensate, even though the sights aren't the problem?
A: I don't believe in drifting the sights over to the right to fix the issue. For one thing, if you ever had to shoot left handed, you'd shooting way off to the right due to both the sights being off and whatever the original problem is. Also, you're incentivising yourself to use whatever bad technique you're using. When you start doing the correct technique, you'll hit to the right, so you'll naturally try to avoid that.
Q: Should I use "Kentucky windage" by aiming to the right of the target?
A: This is not a good idea because under stress, you will be more likely to aim directly at your target. Also, you'd need to calculate how much to hold right at various distances. e.g. if you hold right 2 inches at 7 yards, you'd need to hold right about 4 inches at 15 yards.
Q: On the assumption that the trigger is the problem, should I monkey around with different connectors and trigger springs?
A: If that's your thing, it's fine, but I don't think it will fix it. I've tried a few various connectors and the NY trigger spring, and haven't found it to make any difference with regards to this problem. I don't think for most people that the length or weight of a Glock trigger pull is the real problem. The trigger is not terribly long or heavy. I think the reason that Glock users tend to have this problem more is the size and shape of the grip.
Q: Should I just shoot a ton of rounds and assume I'm going to get better?
A: This is probably a bad idea because you are doing something wrong now, so doing it more is just going to ingrain bad habits. I think it's important to actively try to find and fix the problem.
Q: What about the handgun correction chart that says the problem is "too little trigger finger"?
A: As I mentioned before, I don't think the handgun correction chart has that much benefit. There can definitely be more than one cause for this issue. This may certainly be one of the causes, and it's worth trying to put more of your trigger finger through the trigger guard.
Q: What are some other things to try?
A: Note: I would try isolating each one of these techniques to see if it makes any difference.
- Obviously getting a good instructor to try to diagnose you would be good if feasible.
- Use either closer to the tip of the finger, or closer to the knuckle to touch the trigger. Either way might help. One thing you can try to determine optimum trigger placement is to dry fire the gun, so the striker is down, then repeatedly press the trigger. You'll notice that the sights move in different directions depending on what part of the trigger finger you use.
- Use a harder or softer grip, with either or both hands. Your other fingers sympathetically 'milking' the grip along with your you trigger finger is used can move the gun left.
- Stiffen your shooting wrist, as though you were trying to prevent someone from bending it sideways. This is NOT the same as just gripping harder.
- Try to avoid touching the frame of the gun with your trigger finger. The trigger finger should only be touching the trigger.
- Make sure you always take up the slack in the trigger before beginning your press. If you start with a heavy press while there's still slack in the trigger, it will smash through the slack with momentum and disturb the alignment of the gun.
- Don't let your finger come off the trigger during or after firing. Taking your finger off too fast after firing can disturb alignment of the gun.
- Don't hold the trigger all the way to the rear during or after firing. As soon as the trigger breaks, reset it forward while maintaining contact on it. Letting the trigger finger slam all the way to the rear with momentum can disturb the alignment of the gun.
- If the problem might be flinching, then ball and dummy drills, or just mixing in dry fire with live fire can help. For example, every time you throw a shot to the left, unload the gun and do 5 good dry fires.
- Think about pressing the trigger straight to the rear, and adjust your grip so that can be done to the extent possible. Your trigger finger can't actually move straight back since it describes a curve as it moves, but ideally the tangent to the curve would be straight back at the moment the trigger breaks.
- Try pressing back through the center of the trigger, i.e. through the trigger safety, instead of just contacting the whole trigger in general. Since the trigger face is rounded, it's possible to pull sideways through the trigger, which is obviously undesirable.
- I eventually fixed the problem by putting the Grip Force Adapter on it.
I don't know how to explain it, but my guess is that by increasing the trigger reach, it forced my hand into the right position to pull the trigger straight back. I'm not saying that this solution would be right for everyone, but with my hands, it solved the problem. In general if you didn't want to spend money to try this, you could try altering the size and shape of the grip, maybe with temporary methods like tape to see if it helps.
Some additional references:
- Discusses trigger "milking"
OpSpec training on using a looser grip to avoid this problem
ssdsurf on shooting a Glock well.
ssdsurf on advanced trigger placement.