I read that the Gen 5 had different height sights, because it's setup for a Combat hold (center the front sight dot over the intended POI).  I also read that the sight change is because the Gen 5's marksman barrel changes POI vs the earlier barrels.  This was all read on internet forums, so who knows what is true.

Can sights for Gen 1-4 be used on a Gen 5 G19?  I prefer POI at the top edge of the front sight at 25yds (splitting the bullseye in half with the front sight on a target).

What about swapping G19 barrels?  Would using a Gen 3 barrel in a Gen 5 or a Gen 5 barrel in a Gen 3 require a sight change?

To answer my own question, I did some testing in the woods on my property today. Not my most accurate shooting, but it was all shot standing, off-hand, in fairly low light.

For one, TruGlo TFX Pros (AFAIK there is no Gen 5 specific version of these) do shoot to POA at 10y and 25y on a Gen 5 if you shoot them with POA being the top edge of the front sight intersecting the center of the target.

On the left is my Gen 5 G19's 25y target with the TFX Pros (I do need to drift the rear sight over a little). On the right is the 25y target from my Gen 3 G19 with its OEM plastic Glock sights and a Gen 5 threaded barrel (It has a Grit Grips frame, and the Glock barrel has a Griffin EZ-Lok suppressor mount with a Carry Comp thread protector, but everything else is OEM Glock).




I also tested swapping the OEM barrel in my Gen 5 pistol for a Glock Gen 3 barrel.  Both barrels shot to the same POI with the same POA (and interestingly the Gen 3 barrel's group was a slightly smaller). That busts the myth that the Gen 5 Marksman barrel shoots to a different POI than previous gens.

The top right two groups are from the Gen 5 pistol with the Gen 3 barrel.

The left most and center target are from the Gen 5 pistol with it's original Gen 5 barrel.

The bottom target is from the Gen 3 pistol with a Gen 5 threaded barrel.


Both guns and all three OEM Glock barrels shot to POA at 10 yards. 10 shots were fired at each target.

You've got it sorted out for your 2 Glock pistols, but you can't draw conclusions for Gen 5 vs Gen 1-4 based on 2 pistols.

Glock made the change in the sight height for the Gen 5 because on average the new pistols with the Marksman barrel shot about 2" higher at 25 yds than the previous generations.  Key word being "average"  The .020" taller front sight (steel sights) or .020" shorter rear (plastic sights) regulated the POI to the same as they have always used:  With the front and rear blades lined up and splitting the target the poi should be the tip of the front blade at 25yds.  

It's been my experience that if you shoot 10 brand new Glocks with factory sights most will be dead on, 1 or 2 might shoot a bit high and 1 or 2 might shoot a bit low. Those numbers hold true when extrapolated out to large agencies with 1000's of duty weapons.  It's just the rule of stacking tolerances in manufacturing and using fixed sights. None of them will be off more than a couple of inches at 25 yds which is well within the acceptable accuracy for their intended use and honestly better than the shooting capability of 90% + of shooters.

Glock makes 5000+ pistols per day, so if just 1% shoot a little high and 1% shoot a little low, that's 500 pistols per week where the owner might get on the internet and claim that Glock pistol sights are "off" from the factory.  The other 24,500 pistols are dead on.  

TLDR Fixed combat sights are designed to shoot to the correct POI for the average pistol coming off the assembly line.  Glock does a very good job of that.

Fair point. This is a small sample.

But my understanding, from reading reviews and forum posts, is that Glock changed the sight picture on the Gen 5 G19 at least. Where POA was previously at the top of the front sight intersecting the POI, with the G19 Gen 5 the POA was front sight dot centered over the target. A so called Combat Hold.  So that's why the Gen5 sights are different.  Using Gen 3 sights on a Gen 5 G19 should return the gun to the previous sight picture.

I've never found any proof that the marksman barrel significantly changed the POI and it didn't appears that it didn't with either of my guns.  Nobody could (or would) definitively answer this question either way when I initially posted it.

So my Gen 3 19 has a Gen5 barrel (previous owner swapped the original barrel for a Lone Wolf, and I wanted a factory barrel).  The Gen5 shoots great in it.  I haven't noticed the sights being off or anything (and it's more accurate with the Gen5 barrel)

The 6.1 mm Gen 5 rear sight has a wider notch and a narrower base compared to the 6.5 mm rear sight.   The narrower base provides more windage adjustment in the dovetail compared to the 6.5 mm rear sight.  I prefer the Gen 5 pattern 6.1 mm sight compared to the earlier Gen 3-4 Glock Night Sights.   I find no difference in POA to POI between my 19.3 with gen 6.5 mm GNS and my Gen 5 Glock 19 with GNS.   I can still effectively use the older 6.5 mm GNS but just like the Gen 5 pattern GNS better.   Mu 20.5 has the Gen 5 pattern sights just the appropriate height (6.5 mm) rear sight for the 10 mm.   I’m using the Gen 5 6.1 mm GNS on my Glock 44 and it shoots very close to POA.   I put 6.1 mm Gen 5 pattern GNS on my 23.3 and it shoots POA for me.

I shoot a lot of steel targets between 50 yards and ten yards and I don’t need to change my POA between the pistols with 6.5 mm or 6.1 mm sights.

Literally in this camp right now. I noticed a huge difference in POA / POI with a gen 5 over the gen 4s I have. Most noticeably very low at 5-7 yards.

I understand the combat hold for gen 5s, but it essentially is making me change the way I have pointed and shot pistols my entire life so I have opted to throw gen 4 sights on my gen 5. Just ordered a set off the EE so I hope it has the intended results.

Without going into detail.  I have specific first hand knowledge with regard to Glock Factory sights.  I deal with 100's of thousands of them.
The "combat hold" was never a Glock design.  All Glock Factory sights are designed for their traditional sight picture.  

Again, when you are cranking out 25000 pistols per week with fixed sights, there will be examples that shoot low using the traditional sight picture, but that's not by design.  These are the pistols that shooters will refer to as having a combat hold.  This is exacerbated by the fact that the typical shooter will push the muzzle on a Glock down as the trigger breaks.  Thus the review and forum conclusion that the sights are designed for a combat hold.  

ETA:  The difference in the Gen 5 and Gen 1-4 sight sets is .020" (slightly more than the thickness of the average business card) That adjustment will move the POI 3/4 inch at 7 yds and 2 3/4 inch at 25 yds for a Glock 19.  

That's interesting. Now I wish I would have tried the plastic OEM sights on my Gen 5 before I replaced them.

Good luck!

I'm not a fan of a combat hold either. I just went through that with Sig P229s. I could get used to it if it was my only gun, but  I own a lot of handguns from many different brands. I prefer the point of aim to the consistent across all of them.

My recommendation to anyone wanting to buy replacement sights is exactly that.  Shoot the gun with the factory sights with the ammo you intend to use and then make any adjustments if needed.  

Online sight calculator is helpful:

https://www.ameriglo.com/support/sight-calculator

I use Ameriglo GFT-114 sights for a Gen 1-4 Glock on all my Gen 5s, and they all split the edge of the front sight at 25y.

For any pistol and sight combination, you will have to test and adjust for yourself in the end.

I personally hate the combat hold/drive the dot.

Most report that the factory Ameriglo BOLD sights on the Gen 5s are drive the dot.

Every gen5 I've owned has shot low for me. Since I've been shooting GLOCKs for almost 30 years, I immediately replace the sights with "normal" pre-gen5 ones. I just don't like combat hold.

Glock has always been a combat hold type sights.