Ultimate suppressed upper?

GA Firing Line

DarthVader

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I am curious why not make a "press fit" style gas block with a reduced inlet port?

I know pressing the gas block on would not be a home job for many, but using a bearing heater or hot plate to heat the gas block before installing would create a tight seal once installed/cooled and eliminate the possibility of gas leaks around the block.

This would keep barrel options open and allow you to go back to normal gas if you wanted (if you were able to get the gas block back off that is....)

Below is a CAD (crappy ass drawing) of what I am trying to explain.

View attachment 12551

Edit: It would possibly work as a non press fit, but I just feel it would has gas leakes around it otherwise...
LMT gas blocks are press fit. But for the average Joe, it's not really an option. But I get what you're saying. The BCM blocks are pretty tightly toleranced, unlike some I've seen that would practically spin on the gas journal. With a BCM, what little space there is, will seal itself off pretty quickly.

But the more important factor is the gas hole in the barrel or in your example, the block itself. Making blocks with gas holes in multiple sizes for standard and lightweight profile barrels is probably not economically feasible.

The good news is that someone has figured out a better solution for over gassed barrels, without requiring moving parts like an AGB. Black River Tactical makes a series of inserts that can be threaded into the gas block to reduce gas flow.
 
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Wallace

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LMT gas blocks are press fit. But for the average Joe, it's not really an option. But I get what you're saying. The BCM blocks are pretty tightly toleranced, unlike some I've seen that would practically spin on the gas journal. With a BCM, what little space there is, will seal itself off pretty quickly.

But the more important factor is the gas hole in the barrel or in your example, the block itself. Making blocks with gas holes in multiple sizes for standard and lightweight profile barrels is probably not economically feasible.

The good news is that someone has figured out a better solution for over gassed barrels, without requiring moving parts like an AGB. Black River Tactical makes a series of inserts that can be threaded into the gas block to reduce gas flow.
I have seen those BRT inserts before. Reminds me of re-jetting a carb. I just wonder about how the heat and carbon would affect them long term.
 

DarthVader

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I have seen those BRT inserts before. Reminds me of re-jetting a carb. I just wonder about how the heat and carbon would affect them long term.
I know a couple of guys that have used them and were very pleased. They can't really come loose, because they're captured inside the block. And I wouldn't expect them to clog with carbon. If anything, they'd get frozen into place.
 

boss_hawg

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I am curious why not make a "press fit" style gas block with a reduced inlet port?

I know pressing the gas block on would not be a home job for many, but using a bearing heater or hot plate to heat the gas block before installing would create a tight seal once installed/cooled and eliminate the possibility of gas leaks around the block.

This would keep barrel options open and allow you to go back to normal gas if you wanted (if you were able to get the gas block back off that is....)

Below is a CAD (crappy ass drawing) of what I am trying to explain.

View attachment 12551

Edit: It would possibly work as a non press fit, but I just feel it would has gas leakes around it otherwise...
nailed it
 

Wallace

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I know a couple of guys that have used them and were very pleased. They can't really come loose, because they're captured inside the block. And I wouldn't expect them to clog with carbon. If anything, they'd get frozen into place.

That is what I was thinking. Neat idea if they could be swapped after a couple thousand rounds.
 

DarthVader

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That is what I was thinking. Neat idea if they could be swapped after a couple thousand rounds.
I believe they will last quite a bit longer. Probably would erode at a pace similar to the gas port itself. One guy I know who shoots a lot has been running one for a couple of years now. He installed it into a very over gassed Sabre Defense short barrel. Nothing but praise. It's really meant to be a more or less permanent fix. But if you wanted to swap it out, it could always be drilled out if it couldn't be turned out with a wrench or hex bit driver. If you think about it, the gas block really doesn't accumulate much carbon.
 
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Wallace

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I believe they will last quite a bit longer. Probably would erode at a pace similar to the gas port itself. One guy I know who shoots a lot has been running one for a couple of years now. He installed it into a very over gassed Sabre Defense short barrel. Nothing but praise. It's really meant to be a more or less permanent fix. But if you wanted to swap it out, it could always be drilled out if it couldn't be turned out with a wrench or hex bit driver. If you think about it, the gas block really doesn't accumulate much carbon.
True, I just know heat cycling small fasteners is never ideal. At work, it always results in extraction issues BUT if the rifle cycles reliably, I suppose there is no point in needing to swap if. Especially if you shoot quality ammo.
 

DarthVader

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This basically accomplishes the same thing as the RGP barrel that I have on order. It would allow you to drastically improve gas flow on overgassed barrels. @freedom

From the BRT website:

a10380607fd21354a9aba5050f97720e.jpg


BRT CustomTune Gas Port™





Features

The BRT CustomTune Gas port reduces gas system flow and can correct for barrels with large gas ports that exhibit excessive gas drive.

The port is installed inside the gas block or FSB between the barrel and gas tube.

After installation, it requires no user adjustments or maintenance.

It cannot fall out, come loose or go out of adjustement.

The gas port is available with a variety of port sizes to meet many applications.





Installation requires removal and re-installation of the low profile gas block or front sight base.

Installation is relatively easy and may take less than an hour, start to finish.

Includes FREE SHIPPING. Please allow 3-5 days for items to ship



Suggested Sizes:

5.56 11.5" CAR: .070"

5.56 16" CAR: .063"

5.56 16" MID: .076"

Please email for recommended sizes for specific applications.

Link below has a couple of videos showing results. They even offer a gas block WITH the custom tune port for only $55.
http://www.blackrivertactical.com/concrete5/customtune-gas-port/
 
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DarthVader

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True, I just know heat cycling small fasteners is never ideal. At work, it always results in extraction issues BUT if the rifle cycles reliably, I suppose there is no point in needing to swap if. Especially if you shoot quality ammo.
Yeah, I know what you mean. In this case, it doesn't have anywhere to go, as it's captured internally. They are sold in sets, so a few hundred rounds of experimentation (probably a lot less) would allow you to pick the right one, install it and forget about it.

To me, it's essentially a simpler, less complex and potentially more reliable solution for over gassing than an adjustable gas block. Obviously, initial set up is more labor intensive, but once it's done, you'd be good to go. And Clint is very responsive, so a phone call or email to him would help decide before you start, which port would be ideal for your particular set up.
 
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DarthVader

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OK, all the parts are inbound except for the barrel. It will be another couple of weeks for the barrel.

Build list:

BCM4 upper receiver
BCM KMR Alpha - 10"
BCM gas block and tube
Sionics RGP 11.5 barrel

Already on hand:
LMT enhanced carrier
BCM bolt, cam pin, firing pin, etc
BCM Gunfighter charging handle
Magpul MBUS Pro sights
Aimpoint T1 w/ Bobro mount
BCM KAG
Surefire Mini Scout on a KAC keymod mount

All riding on a Form 1 BCM lower with Geissele SSA trigger and Vltor A5 buffer system. This thing is going to be sweet.
 

Righter13

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OK, all the parts are inbound except for the barrel. It will be another couple of weeks for the barrel.

Build list:

BCM4 upper receiver
BCM KMR Alpha - 10"
BCM gas block and tube
Sionics RGP 11.5 barrel

Already on hand:
LMT enhanced carrier
BCM bolt, cam pin, firing pin, etc
BCM Gunfighter charging handle
Magpul MBUS Pro sights
Aimpoint T1 w/ Bobro mount
BCM KAG
Surefire Mini Scout on a KAC keymod mount

All riding on a Form 1 BCM lower with Geissele SSA trigger and Vltor A5 buffer system. This thing is going to be sweet.
Does the SS color of the gas tube ever irk you?

And no adjustable gas block?
 

DarthVader

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Does the SS color of the gas tube ever irk you?

And no adjustable gas block?
I really don't ever notice the tube.

And no AGB. I'm not a fan, just because I don't want any possible failure points associated with the gas system. And the point of this particular barrel is to avoid the need for one anyway.
 

Righter13

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I really don't ever notice the tube.

And no AGB. I'm not a fan, just because I don't want any possible failure points associated with the gas system. And the point of this particular barrel is to avoid the need for one anyway.
Makes perfect sense. For some reason I thought your initial build list listed an AGB.

Went back to first post and noticed it didn't lol.

Went with the same gas block but went with a WMD gas tube bc it's black lol.
 
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boss_hawg

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OK, all the parts are inbound except for the barrel. It will be another couple of weeks for the barrel.

Build list:

BCM4 upper receiver
BCM KMR Alpha - 10"
BCM gas block and tube
Sionics RGP 11.5 barrel

Already on hand:
LMT enhanced carrier
BCM bolt, cam pin, firing pin, etc
BCM Gunfighter charging handle
Magpul MBUS Pro sights
Aimpoint T1 w/ Bobro mount
BCM KAG
Surefire Mini Scout on a KAC keymod mount

All riding on a Form 1 BCM lower with Geissele SSA trigger and Vltor A5 buffer system. This thing is going to be sweet.
badass setup.

bcm is my top tier brand of choice and I've heard great things about sionics barrels. I can't see the appeal of noveske at the price points that are offered.

I love a 11.5 or 12" setup too. I think it's right in the sweet spot of portability and effectiveness for the 5.56 round.
 
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DarthVader

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badass setup.

bcm is my top tier brand of choice and I've heard great things about sionics barrels. I can't see the appeal of noveske at the price points that are offered.

I love a 11.5 or 12" setup too. I think it's right in the sweet spot of portability and effectiveness for the 5.56 round.

I honestly would put Sionics right up there with BCM in terms of quality, especially the barrels, bolts, carriers, etc. I prefer the BCM upper receivers, as they are made in house by BCM.

As far as Noveske goes, their stainless barrels are very good. But the N4 Barrels aren't really all that special anymore. Too many good competitors in the milspec 4150 barrel category. The N4 was unique when it first came out because no one else offered a hammer forged barrel, but that has long since changed.
 
Last edited:

chance

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I wonder if an "interchangeable" gas port is viable. Basically an interchangeable restricter that fits in the barrel and is held in by the gas block. You could choose between a few sizes depending on your need, then build it once and never mess with it again
 

DarthVader

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Mar 25, 2015
1,175
390
113
Henry County
Zip code
30253
This basically accomplishes the same thing as the RGP barrel that I have on order. It would allow you to drastically improve gas flow on overgassed barrels. @freedom

From the BRT website:

a10380607fd21354a9aba5050f97720e.jpg


BRT CustomTune Gas Port™





Features

The BRT CustomTune Gas port reduces gas system flow and can correct for barrels with large gas ports that exhibit excessive gas drive.

The port is installed inside the gas block or FSB between the barrel and gas tube.

After installation, it requires no user adjustments or maintenance.

It cannot fall out, come loose or go out of adjustement.

The gas port is available with a variety of port sizes to meet many applications.





Installation requires removal and re-installation of the low profile gas block or front sight base.

Installation is relatively easy and may take less than an hour, start to finish.

Includes FREE SHIPPING. Please allow 3-5 days for items to ship



Suggested Sizes:

5.56 11.5" CAR: .070"

5.56 16" CAR: .063"

5.56 16" MID: .076"

Please email for recommended sizes for specific applications.

Link below has a couple of videos showing results. They even offer a gas block WITH the custom tune port for only $55.
http://www.blackrivertactical.com/concrete5/customtune-gas-port/

I wonder if an "interchangeable" gas port is viable. Basically an interchangeable restricter that fits in the barrel and is held in by the gas block. You could choose between a few sizes depending on your need, then build it once and never mess with it again
That's basically what the BRT inserts shown above accomplish.
 
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