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Yes, there are 2 different versions. The one for the 10.4” barrel has a 1mm vent, and the adjustable regulator has a 1.6mm port for unsuppressed shooting and a 1.4mm port for suppressed shooting. The 14.5”/16” barrel version has a 1.5mm vent, and the adjustable regulator has a 1.4mm port for unsuppressed shooting, and a 1.2mm port for suppressed shooting.
Gracias mate.

I know, you’re always right regardless.

Carry on, it’s all yours.
 

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Yes, there are 2 different versions. The one for the 10.4” barrel has a 1mm vent, and the adjustable regulator has a 1.6mm port for unsuppressed shooting and a 1.4mm port for suppressed shooting. The 14.5”/16” barrel version has a 1.5mm vent, and the adjustable regulator has a 1.4mm port for unsuppressed shooting, and a 1.2mm port for suppressed shooting.
Now I'm really interested to see if anyone can say for certain which AGB version HB and HK Specialist are selling. They are advertised as 14.5"/16", but IIRC the vent size was tiny, smaller than both my 10.4" vented and MR556 GBs. They were also stamped 36 on the valve.
 

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AGB Body.jpg AGB Regulator N Input Port 1.7mm .jpg AGB Regulator S Input Port 1.2mm.jpg AGB Vent .9mm.jpg

I purchased an AGB from Hurricane Butterfly and I purchased a 10.4" barrel (They weren't purchased as a matched pair...just purchased in the same time frame). The barrel gas port is 1.7mm. I took apart the AGB to measure the regulator gas ports and I took pictures. The vent was .9mm. I'm using pin gauges and I could not get a 1.0mm pin in the port. I tried a .95mm pin and that wouldn't fit. The .9mm was the next size that fit. I see a lot that list the 1.0mm vent sizes so I was a bit uneasy regarding a .9mm; never saw that listed by anyone but that's what I got. I removed the regulator and the "N" port was 1.7mm and the "S" port was 1.2mm. I also measured each pin, while in the respective port, with a Mitutoyo 500-196-30 AOS Absolute Caliper 0-6" for verification and measurement.

There is a dimple on the AGB body (see picture); I don't know what that means but ToyCop said that it could be a 10.4" AGB. HB listed it as a 14.5/16 AGB.

I also bought a Brownells 416 parts kit and I'll provide the measurements for that next. It's a non adjustable vented gas block and I don't know what the donor barrel was; I'm assuming 14.5/16.
 

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Here's the measurements and pictures for the gas block that came with the Brownells hk416 parts kit:

Gas Black Input Port (at barrel) and port that leads in to the piston cylinder: 2.5mm
Gas Block Vent: 1.7mm

GB Body.jpg GB Vent.jpg
 

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I recently got a dimpled AGB from RKS and it doesn't have the sling loops. The gas port looks tiny so I'm assuming its for a 10" barrel since they don't list it on their page.
 

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View attachment 242448 View attachment 242450 View attachment 242452 View attachment 242454

I purchased an AGB from Hurricane Butterfly and I purchased a 10.4" barrel (They weren't purchased as a matched pair...just purchased in the same time frame). The barrel gas port is 1.7mm. I took apart the AGB to measure the regulator gas ports and I took pictures. The vent was .9mm. I'm using pin gauges and I could not get a 1.0mm pin in the port. I tried a .95mm pin and that wouldn't fit. The .9mm was the next size that fit. I see a lot that list the 1.0mm vent sizes so I was a bit uneasy regarding a .9mm; never saw that listed by anyone but that's what I got. I removed the regulator and the "N" port was 1.7mm and the "S" port was 1.2mm. I also measured each pin, while in the respective port, with a Mitutoyo 500-196-30 AOS Absolute Caliper 0-6" for verification and measurement.

There is a dimple on the AGB body (see picture); I don't know what that means but ToyCop said that it could be a 10.4" AGB. HB listed it as a 14.5/16 AGB.

I also bought a Brownells 416 parts kit and I'll provide the measurements for that next. It's a non adjustable vented gas block and I don't know what the donor barrel was; I'm assuming 14.5/16.
I saw this the other day that shows similar numbers to what you measured
https://www.gunbroker.com/item/822070822
 

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I just re-measured to verify that "N" is 1.7mm and not 1.55mm and it is, without a doubt, 1.7mm at the "N" port (V=.9mm, N=1.7mm, S=1.2mm). The AGB that you referenced looks identical to mine, dimple and all. I still don't know what "officially" is the corresponding HK barrel size that it supports, but that's what this beast is.

I used it with the HB 10.4" barrel on the BRN-4 lower with the HK416 Parts, set to "N", and it was fully cycling but it wasn't triggering the next round (full extraction, loading next round, pull trigger, no bang). I used a Go-No-Go gauge to verify barrel fit and it was REAL tight on the Go gauge, like it would barely go in to battery. I'm hoping that this is a barrel extension break-in issue and that I need to put some more rounds through it. I used the same lower with an MR556 upper and it worked flawlessly, so the lower should be considered solid. I'm a NOOB when it comes to building these things and am leveraging the expertise/experience of the members of this forum and others to learn quickly...it's mostly working.

So, given the calculus that IT, and others, have provided, would this AGB work with a 10,4" barrel that has a 1.7mm gas port? Anyone?

Cheers,
 

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Here's the measurements and pictures for the gas block that came with the Brownells hk416 parts kit:

Gas Black Input Port (at barrel) and port that leads in to the piston cylinder: 2.5mm
Gas Block Vent: 1.7mm

View attachment 242466 View attachment 242468
Can someone share the various VENTED 416 gas block versions for 10.4" and 14.5"/16/20? I am looking for HK Factory part numbers for the vented versions with and w/o sling loops. Thanks!
 
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