Sight issues POA / POI

Discussion in 'Sights, Optics and Lasers/Lights' started by swaff, Jan 16, 2017.

  1. swaff

    swaff

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    I am having some inconsistencies in my Glock 17 sights. My shot groups are pretty tight at 10 yards, but POI is slightly left of POA. I'm pulling the trigger straight back and during all my deyfire practice, I am able to break the trigger without disrupting the front sight. I am left eye dominant but right handed- shooting with both eyes open and bringing the sights in front of my left eye to shoot.

    I pushed the rear sight to the right a little, and this seemed to do the trick for live rounds, but I have one inconsistency: when I load in my Laserlyte practice bullet into the chamber, the laser POI is right, just as expected by the placement of the rear sight being to the right also. I'm not having any trouble with shooting low or high.

    Any ideas what's going on with the live rounds? I'm not understanding why live rounds are shooting left, but the laser is shooting right. Any help is appreciated.

    Swaff
     
  2. harold63

    harold63 I'm not retired

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    The laser is to get you on paper. You don't worry about what it does, after that. Get everything matched up by shooting your pistol off of a rest, using the sights. If your rested shots hit the X, but your off hand shots hit left (or right, high, low), you'll know you need some work with keeping the gun on target, shooting off hand. Also, don't worry about your rear sight being a little left or right to get your rested shots on the X. I have 3 G41's and 3 G34's and not a single one has the rear sight perfectly in the middle.
     
    Last edited: Jan 16, 2017
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  3. GP4L

    GP4L

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    Something you can do to help; is load a random snap cap/dummy somewhere in one of your magazines. When you trick yourself attempting to fire on that snap cap at the range, evaluate yourself regarding how much/little the muzzle moves when the trigger breaks. Since you're staring at the front sight anyways, you should have no trouble seeing it potentially move. If you yank the gun thinking you are firing a live round, the answer to your question is: it's you. If your trigger pull still looks good, it's just your Laser. They can be hit or miss. I have a muzzle laser sight with various attachments for different calibers. It works very well on my Glocks, not so much on my rifles for some reason (left/right significantly off). Like said above, good enough to get on paper.
     
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  4. sciolist

    sciolist On the Border

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    'What's going on with the live rounds' is that they hit where the gun his pointed when it discharges. If that's not where you saw the sight picture, you weren't looking at the sights when the gun went off. So stop messing around with lasers and learn to call shots.

    When you can call shots, you can sight in a gun. Until you can call shots, you're just chasing your tail.
     
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  5. jhertzler

    jhertzler

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    It seems to me that whenever someone has a different POI relative to POA then it's always the shooter doing something wrong. Sometimes this is the case. But, any gun is liable to shoot to a place slightly different than where you're aiming. It's one of the hazards of having fixed sights and why adjustable sights are sometimes preferred. Drifting the rear sight is a good fix. Sometimes you can do some good by trying different ammo that might shoot more to aim, or to handload ammo, trying different powders, charges, and bullets.
     
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  6. sciolist

    sciolist On the Border

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    POA is arbitrary. POI is where the gun was pointed when it went off - it's that simple. In order to reconcile the 2, a shooter has to have the visual and manual capability to see where the sights are when the gun discharges. If you can't do that, you're just wasting time.

    Yes, there is adjustment in the sights, including the ability to change sights. When a discussion begins with statements about "pretty tight" groups at 10 yards, it's clear where the problem lies. If you can't put 5 rounds in one hole at 10 yards, figure out how to do that first. Then worry about moving the hole.
     
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  7. Rocky7

    Rocky7 Proud NRA Life Patron Member, Life GSSF member

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    Sorry OP, its you not the sights.
     
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  8. Glock Commander

    Glock Commander

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    Operator error. Leave the sights alone and eventually you will be printing spot on. The attachment will give you an ideal what you are doing.
     

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    Last edited: Jan 16, 2017
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  9. 10mmJamie

    10mmJamie

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    Well, I have an interesting 'uniqueness' with my fav Glock- Mod40MOS; To get the impacts centered I had to keep the rear sight full-travel to the left as it was when I received it new.
    I have even tried the ported 9" Wolfe BBL...same results.

    My-30, -36- -27 all shot to aim and their rear sights are dead-center.

    Any ideas?
     
  10. Cpt.America

    Cpt.America

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    I love threads like these. "It's you! The gun is perfect!". USUALLY this is true, but isn't necessarily. For example, I have 7 hand guns, 4 of which are glocks. All of my hand guns have the same POI and POA, except for one. One of my glocks, my gen4 G34, shoots left about 2-3 inches at 10 yards. My G19s and my G17s? POI and POA are identical, and are dead center.

    No, I am not moving the muzzle. I shoot about 2k pistol rounds per month, and dry fire almost daily. Yes, I can repeat it from a bench rest with slow, deliberate, concentrated trigger pulls. I had to drift my G34 rear sight all the way to the right as far as it would go (the factory rear adjustable sight) in order to mate my POI and POA. What is causing it? no idea.
     
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  11. Mntneer

    Mntneer

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    Ignore most of the previous responses; except CptAmerica. Since your POA = POI with the laser bullet, the problem isn't the shooter or the sights. A couple possiblities come to mind: the Lazerlyte isn't aligned (defective), you aren't inserting it properly or damaged o-ring, or the crown of the barrel is messed up and slinging lead in the wrong place. The Lazerlyte is a great dryfire training tool!
     
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  12. harold63

    harold63 I'm not retired

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    Only in cases where the gun has poor mechanical accuracy, and in those cases, the gun will still print a decent sized group at self defense distances. The barrel and slide can only move around so much while the gun is being fired. It is still going to send the bullet to the place the barrel was pointed at. You just have to align your sights to that spot, and it should be done off a rest if you are less than skilled. That will determine if the shots are being 'flinched' when shooting, off hand. FWIW, a rested shot will match an off hand shot as long as the shooter is doing what he/she is supposed to do.
     
    Last edited: Jan 17, 2017
  13. harold63

    harold63 I'm not retired

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    Unfortunately, this isn't always the case. A barrel can and will lock up and shoot to a different spot than what perfectly centered sights say it should. Let's say you get your new WC barrel bushing for your 1911 and it's .003'' thicker on one side than the other. You can't see this with the naked eye, but if the sights are perfectly centered on the gun, it is not going to hit the X if you're aiming there (eta - this is extreme and would really be more noticeable at longer distances).
     
    Last edited: Jan 17, 2017
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  14. harold63

    harold63 I'm not retired

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    11 posts and 0 likes. That a 0 percent of anyone agreeing with you. The people that compete and have replied to this thread all say it's more shooter related. Cpt.America says the OP will eventually begin to shoot where the sights are aimed verses aligning the sights to where the barrel is pointing when the gun is fired. Ignore the people that know if you want to. It's not going to change the fact they are more than likely spot on.

    Semi's will not always hit the X when the sights are perfectly in the middle and they will not always hit the X when your laser gadget says it should. Use a laser with a weak recoil spring and you'll chase your group all day.
     
  15. Rocky7

    Rocky7 Proud NRA Life Patron Member, Life GSSF member

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    Oh, I agree on revolvers and other pistol designs that it's chances of having to adjust for right/left situations exist.

    Unless there is a manufacturering error or part that breaks the 50 Glocks I've used in the past shot POA/POI.

    I've used adjustable Bomars in the past to compete, but looking back that 2" adjustment at 35 yards is not needed.

    I've put as much as 27k rounds a year down range and dry fired daily for many years. Reloading also suggests that out to 45 yards the gun, ammo and sights will outshoot you.

    The deviation in reloading components such as bullets in their weight and profile can have a larger impact than most can expect.

    Suggest you try using more finger with your live ammo.
     
    Last edited: Jan 17, 2017
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  16. harold63

    harold63 I'm not retired

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    Mass production causes it. No barrel bushing causes it. A burr on the barrel hood can cause it. Guns coming off the line when a retool is needed. That's just for starters.
     
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  17. Mathemagician1

    Mathemagician1

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    One thing you can do to is rotate the laser 90 degrees at a time. If the dot rotates along with it, it is likely that the laser is not pointing straight and needs adjustment. However, if the dot stays put when you rotate the laser you can be confident that everything is lined up properly and you can focus 100% on your technique with no distractions.
     
  18. swaff

    swaff

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    Hey everyone, thanks for all the great replies! I am going to keep the rear sight drifted right for now since I am hitting POA=POI with live rounds and try to investigate the laser some more. I emailed Laserlyte and they said the o-rings could be worn and that would make the laser impact location off every time. Even on a rest with a slow and smooth pull, the shots print left WHEN the rear sight is dead center. When pushing the rear sight right a little, the pistol is zeroed from the rest.

    I do realize that I can still improve my trigger pull and other skills, so I will keep on working on that along with my dry fire too. I'll report back after some time and let everyone know what I found.

    Swaff
     
  19. ithaca_deerslayer

    ithaca_deerslayer

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    It is very useful to test your sights, point of aim, and group size while sitting at a bench and resting your wrists on a sandbag, taking well aimed slowly fired shots with a surprise trigger break.

    You doing that is easily twice as accurate as you standing up and shooting, because you eliminate a lot of the shooter variables :)
     
  20. pAZ Ron

    pAZ Ron

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    I had one G23 with factory sights that I had to drift the rear sight all the way to the right possible with out hanging over the edge of the slide to get my groups centered at 25 yds off a bag rest. Could not correct it with my trigger finger placement nor with ammo selection i.e. things that worked with other guns. But that one was an exception.

    Had an aftermarket night sight available off another gun, installed it dead on center, and groups were immediately centered with same ammo. So even though it looked alright, I concluded it was something wrong with the OEM sight.

    All my other Glock and other brand guns with OEM Glock sight, other brand factory sights, or an aftermarket sight .... the sights are centered and groups start centered or can be moved centered by adjusting to get the appropriate trigger finger placement.
     
    Last edited: Feb 23, 2017