I have a question for Glock experts/armorers

[ny32182]

I took my new G34 out to the static range yesterday to fire 120 rounds to confirm function and sights.

Well, the function part went fine, but I had to crank the adjustable rear all the way to the left to get the group centered at the distance I was shooting; approximately 12 yards I'd guestimate. I can probably look up the exact distance in the club manual if anyone cares.

Is this a problem? I've never moved a set of pistol sights from their factory position in my life before now.

 

[VA27]

It's common and it's not a problem. I'm not sure why, perhaps it's a product of the polymer frame and the recoil dynamics of the gun in your hand.

I got my first G17 in 1989 and I've had several since and I had to adjust all of them. Due to frame mass (or lack thereof) Glocks also seem to be sensitive grip pressure. If your grip is not consistent from shot to shot you'll have some vertical stringing of groups.

I've been an instructor and Glock Armorer since 1990 and in that time I've trained literally hundreds of folks on the Glock. The sight pusher is my friend.

 

[9mmepiphany]

Is this a problem? I've never moved a set of pistol sights from their factory position in my life before now.

i don't think i've ever seen a G34 on the line with the adjustable sights still on them...don't most folks replace them right off

 

[ny32182]

I do plan to replace them probably with a fiber optic front and adjustable black and/or dotted rear as I'm not much of a fan of the "dot in a box" since I have little experience with it, but I will probably start shooting it before that happens.

VA27, thanks... when you say you adjust them, by how much? It isn't going to take much for the base of a fixed rear to be hanging off the slide?

I didn't have any notable "stringing"... it was more that the left edge of the group was aligned with the front sight with the rear centered. I had to adjust the rear *almost* all the way over to get the group centered.

Might this vary with the ammo? I was using a load developed in my G19.

 

[Hk Dan]

If it has a screw on front sight, that sight can turn in the final act of tightening the screw. THAT can cause a pretty dramatic adjustment in the rear sight to be "on". If you have the plastic stake on sights, that ain't it.

Next--get your grip nailed, and move your finger on the trigger. Experienced shooters CAN shoot pretty decent groups even when jerking, slapping, or pushing the trigger, they're just not in the right place. In other words, you could be screwing up, but being very consistent in your execution (see? A silver lining...LOL)

I've never seen a GLOCK require a dramatic site adjustment. It's always been a shooter adjustment--always. Every time.

 

[pvthouse]

All glocks come from austria with adjustable sights to give them added import points and then when they get to smyrna, ga some get changed to fixed sights and others don't. Just thought I'd throw that out there.

 

[ny32182]

Well, I generated these groups with deliberate slow fire and a relatively perfect sight picture... never had this happen with any other pistols including two other Glocks. But I do plan to take out the rifle front rest next time to be 100% sure.

Assuming that is the mechanical POI, what then?

I don't see any screw in the front sight; I think it is the basic plastic front and factory adjustable plastic rear.

 

[GForceLizard]

Are you left handed? I had to move my G17 sights right, right handed shooter. I hear this is very common.

 

[fineredmist]

The G34 and 35 are sensitive to differences in the way you grip the gun and the position of your finger on the trigger. You need a firm hold, not a death grip. place the middle of your finger on the trigger and move it straight back. The longer sighting radius (barrel) will magnify any differences in your hold. You must fine the "sweet spot" of your grip and trigger position and use it consistently. Remember, the longer the barrel the greater the movement.

 

[bratch]

Have you let anyone else shoot it?

I've seen several people in classes complaining that their Glock sights are not correct only to have the instructor shoot it POA/POI.

 

[ny32182]

Yes I am left handed.

I will let a friend shoot it next practice in addition to bringing the rest.

Remember, the longer the barrel the greater the movement.

Well... the longer the barrel (sight radius) the more movement you will see in the front sight, but the bore axis is not actually moving any more or less as a direct result of the length. I think that might be what you are saying; just want to confirm.

This isn't my first pistol, or my first Glock folks... nevertheless I recognize and acknowledge that maybe I can't shoot straight. This will be re-verified and independently verified at my earliest convienience. However, IF it turns out to not be me, should I send this gun back and/or have it examined by an expert? We've got one "no, it is normal" vote from VA27 above so far.

 

[Zak Smith]

None of my Glocks have needed windage adjustment from nominal center of the rear dovetail.

 

[bratch]

The only Glocks I've seen need windage were people adjusting for something they were doing.

 

[ny32182]

Thanks for the input. I will post the results whatever they may be.

 

[bratch]

I'll be interested to see what it is hopefully it's as easy as adjusting the sights.

 

[ny32182]

It hits POA for me with the sights adjusted where they are right now.

 

[ny32182]

I shot the gun off a rest yesterday.

I did change one thing... I scaled the load back slightly because this is going to be a dedicated IDPA game gun, and the load I was using before was legal from my G19. So I scaled it back just a little and need to re-chrono, but I suspect it will be about the same velocity as the old load from the 19.

But anyhow... slightly reduced load from before, from the rest I was hitting about 1.5" left at 15 yards, so, I did move the rear back in toward center a little bit... not all the way, but now it is just a slight bit to the left. From there I moved it back to the second berm at a stepped off 24 yards, offhand and fired 10 as fast as I could get a decent sight picture (essentially shooting at match speed) and was hitting a little high but the windage center was dead on. I also polled some other 34 shooters at a club match on Saturday and about half said they moved their sights a little, so now I think the pistol is fine. I am going to change the sights entirely, but that is a different discussion.

 

[mwcharger]

well that all depend on how much it bothers you, my philosophy (or atleast after my last project ) is if its not broke dont fix it.

you could always use a sight pusher or a flathead screw driver with hammer, to push the sight housing. but if your shooting on point i would leave it

 

[bratch]

Hearing about the ammo doesn't surprise me after what happened to us yesterday.

A buddy of mine who is a very good shooter was shooting way left (off an IDPA head) at 25 yards. He ran several mags through his 4th Gen G17 with the same results. He picked up his 4th Gen G22 and was hitting a 3x5 card at 25y.

He was using plain 115gr reloads in the 17 and hot 180gr reloads in the 22. Both guns wear Ameriglo Operator Pro sights that are centered.

He then put Ranger 127gr +P+ in the 17 and was again hitting the 3x5 at 25y. Back to the 115gr reloads and he was off the target again.

Something about the 115gr reloads was not agreeing with his pistol.

 

[Hk Dan]

Glad to hear that you got it resolved to satisfaction!

One other note? I've noticed that when you try to do extremely precise shooting with a GLOCK, and work the trigger like a rifle (creeping up on the trigger and slowly adding pressure until the shot breaks), they tend to throw the hits around on ya. If you do a confident, smooth, straight press--more like IDPA shooting--they hit where the sights are sitting.

I can't explain it, it's just an observation I've made.

Dan

 

[ny32182]

Hmm, well I wasn't looking for that kind of difference specifically, but it wouldn't surprise me. Overall group size was tighter with the rest of course, and I was doing a creeping rifle-like trigger pull off the bench.

The elevation thing is curious; at 24yd it was enough to where I would have to aim at the bottom of the zero zone to get a good hit. I think I see what is going on though:

Off the bench, I'm using the top of the sight notches as the visual reference and hitting POA. This always worked for me with the 19 because the factory NS dots didn't contrast that much at all in the daylight conditions of an IDPA match, and I wasn't really picking them up as the point of visual focus.

With the 34, the bright white "dot" on the front sight is what I naturally pick up visually at speed. However, it is NOT on the top of the front post. At the end of the range session was wondering why I was shooting higher at 24yd line, and I think the answer is that when I center the white dot in the "box" at speed, the top of the front sight post is actually higher than the top of the rear sight notch, leading to aiming higher than intended. The consequences aren't that much up close but are magnified at 24yd. I will want to find some sights that eliminate this.

Also, a headshot at 25yd is a tough shot in my book!