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I like the sound of the DIY drill your own size ports idea. It gets my vote.
 

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I have a Scar 20S and bought a Surefire SOCOM 762-RC2 Suppressor (Currently in NFA Jail) so that I don't have to mess with the Gas Jets and can just keep everything stock.

Question, if I install this 3-Select Gas Regulator on my Scar 20S, how are the 3 position compared to stock?

1) The 1st setting at 12 O'clock is the same as the stock gas regulator. (Use to shoot without suppressor)

2) Is the 2nd setting at 10 O'clock also the same as the stock gas regulator? Or does it reduce the gas pressure more than stock? (Use this setting when running a suppressor)

3) The 3rd Setting 8 O'clock? will reduce the gas pressure even more than the 2nd setting. (This is especially good when using a suppressor with High gas pressure).

So I can see the benefits of using this 3-Select Gas Regulator when running a Suppressor on a SCAR 20S BUT will it still benefit if my suppressor is a Surefire SOCOM 762-RC2 which already has low gas pressure compared to other suppressor.
 

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I have a Scar 20S and bought a Surefire SOCOM 762-RC2 Suppressor (Currently in NFA Jail) so that I don't have to mess with the Gas Jets and can just keep everything stock.

Question, if I install this 3-Select Gas Regulator on my Scar 20S, how are the 3 position compared to stock?

1) The 1st setting at 12 O'clock is the same as the stock gas regulator. (Use to shoot without suppressor)

2) Is the 2nd setting at 10 O'clock also the same as the stock gas regulator? Or does it reduce the gas pressure more than stock? (Use this setting when running a suppressor)

3) The 3rd Setting 8 O'clock? will reduce the gas pressure even more than the 2nd setting. (This is especially good when using a suppressor with High gas pressure).

So I can see the benefits of using this 3-Select Gas Regulator when running a Suppressor on a SCAR 20S BUT will it still benefit if my suppressor is a Surefire SOCOM 762-RC2 which already has low gas pressure compared to other suppressor.
Save your money & buy a selection of PMM gas jets to "tune your gun with the SOCOM RC-2. It's the recommended suppressor for the SCAR 17 and Jarod has a video over at Parker Mountain Machine that goes over all things SCAR/suppressor related (PMM FAQ Page). Very much worth watching. I settled on a 1.45 mm jet running on the suppressed (10 o'clock) position...
 

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Save your money & buy a selection of PMM gas jets to "tune your gun with the SOCOM RC-2. It's the recommended suppressor for the SCAR 17 and Jarod has a video over at Parker Mountain Machine that goes over all things SCAR/suppressor related (PMM FAQ Page). Very much worth watching. I settled on a 1.45 mm jet running on the suppressed (10 o'clock) position...
Thanks for the info. But remember, I have a Scar 20S. Unlike the 17S, everytime i need to swap gas jets, I have to take off the barrel which will mess up my scope again. The idea of taking off and on and off and on the barrel each time to fine tune which gas jet to use doesn't sound fun and I rather spend $150 for a 1-time install.

FYI: The SCAR 20S stock gas jet is 1.40, so if I do go that route, it'll probably be either a 1.30 or 1.35 but again, I'll only have 1 settings and assuming the stock setting will still work with my ammo of choice without running a suppressor. Sometimes it's easier to just pay for the convenience. (Already have over $9k invested, what's another $150, haha)
 

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Each setting on the 3-position regulator was stated that it is 20% less gas into the system...

Just because you have a SOCOM RC-2...the system is still overgassed from factory (PMM explains why it is the way it is)...I asked FN if there is any commercially available suppressor that is ok to use...they said no...so proceed with that...

If you are running suppressed all the time on your 20S...you can actually get away with a 1.2MM jet...if you want a happy medium...go with 1.3mm...that is what I am doing...but as you said...for us 20S users...the 3-position plug makes more sense then to SCAR 17.
 

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Thanks everyone for your feedback. Sounds like it's time to order the 3-Select Gas Regulator which is good since I'll have to remove the barrel anyways to replace the stock FH with the Surefire SOCOM Muzzle Brake. That'll be a good time to swap the gas regulator also.
 

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Sorry Rookie Question.

The 3-Select Gas Regulator is a simple "Plug & Play" upgrade correct?

Meaning all I have to do is remove the stock gas regulator on my Scar 20S and replace it with this 3-Select Gas Regulator.

Leaving the gas jets alone at 1.4 which is what I want to do.

I'll be running a Surefire SOCOM 762-RC2 Suppressor with a Surefire SOCOM Muzzle Brake on my SCAR 20S.
 

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Sorry Rookie Question.

The 3-Select Gas Regulator is a simple "Plug & Play" upgrade correct?

Meaning all I have to do is remove the stock gas regulator on my Scar 20S and replace it with this 3-Select Gas Regulator.

Leaving the gas jets alone at 1.4 which is what I want to do.

I'll be running a Surefire SOCOM 762-RC2 Suppressor with a Surefire SOCOM Muzzle Brake on my SCAR 20S.
Correct.
 

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After speaking to Eddie from MotoTech, I ordered the 3-Select Gas Regulator for my Scar 20S.

I'll test out the 3-Select Gas Regulator running with stock gas jet (1.4mm for 20S) along with a Surefire SOCOM Muzzle Brake and Surefire SOCOM 762-RC2 Suppressor.

Because the Surefire SOCOM 762-RC2 Suppressor is already considered a low backpressure Suppressor, it'll be Great to test out the additional 2 settings for suppress shooting on the 3-Select Gas Regulator.

I know it may be cheaper to just buy a bunch of gas jets/screws from PMM and do some trial and error but with the 20S, the Time and Money spent going back and forth to the gun range and having to take on and off the barrel each time you swap gas jets/screws VS going to the gun range 1 time and only paying 1 time and testing with a simple turn from position 1 to 2 to 3.

Even though others have use the Surefire SOCOM 762-RC2 Suppressor with stock gas jets/screws and just turning the Selector from unsuppress (12 O'clock) to suppress (10 O'clock) with no issues, having a 3rd position to even reduce the gas-pressure even more is a PLUS!!
 

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Discussion Starter #36
I just got done signing off docs with the upstairs department so I can talk freely in the forums.
I currently have some willing and knowledgeable people out in the wild running 3-Select in their SCAR20s.
The data is coming and I think even a short demo video like the ones on the youtube channel.

3-Select seems to be VERY well received and gaining popularity every day.
Definitely encourage end-users to post experience and questions here.
 

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Eddie, did I miss it or did you publish the size of the ports on your valve compared to stock?

Is the smallest hole the same size as stock? And the 2nd the same as the stock suppressor setting with a 3rd that bleeds even more gas for higher back pressure suppressors?

Or if they are different, how do the 3 settings compare to stock?
 

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Hopefully Eddie will have some time available and answer these 3 specific questions for us.

The 20% reduction explanation does help but when you say "The second and third settings have roughly 20% less gas exposure to the piston as you turn the device". It's hard to compare when I don't know how much less gas exposure to the piston the 2nd setting on the stock gas regulator is.

Let's just say for EXAMPLE - If the 2nd setting on the stock gas regulator reduces gas exposure 10% and the second setting on the 3-Select Gas Regulator reduces gas exposure by 20% then I know the 3-Select Gas Regulator on the second setting is reducing more gas exposure than the stock gas regulator on the second setting and when you turn the selector to the third setting, you're reducing even more gas exposure. But is the third setting really ANOTHER 20% less gas exposure to the piston or is it really 10% less on the second setting and 10% less on the third setting? And 20% less gas exposure to the piston overall?

The SCAR 3 Selector has a identical to OEM 1st hole opening on the first setting, the second and third settings have roughly 20% less gas exposure to the piston as you turn the device.

So Here's The 3 Questions Everyone Wants to Know About The 3-Select Gas Regulator:

Question #1: Is the smallest hole the same size as stock?

Question #2: Is the 2nd the same as the stock suppressor setting with a 3rd that bleeds even more gas for higher back pressure suppressors?

Question #3: Or if they are different, how do the 3 settings compare to stock?

BONUS QUESTION: How much less gas exposure to the piston on the second setting does the stock gas regulator provide?
 

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Discussion Starter #39
Alright, Got out of the shop for a little computer time.
I need to get that TapATalk app back on my phone.

Seeing as the device has been out in the wild long enough and it can't be a secret anymore, I am going to let the sizes out of the bag.
3-Select hole sizes go as follows...

Select #1 (first detent when you install the device): 0.104"
Select #2 Turn the device one click CCW if you where looking at the muzzle (try not to do that) you get: 0.086" . You also get 1 small venthole exposed to the gasblock's vent-channel
Select #3 Last detent stop you get 0.0625" hole size. You also get a full 2 small ventholes exposed to the gasblock's vent-channel.

As best as I can measure from buying 4 new and my 2 SCAR's gas selectors, your OEM full gas (1st select) setting is an orifice size of 0.104".
This is what I chose for my first select on my device. Again, I want people to be able to start from an OEM like baseline and be able to go back to OEM un-suppressed settings.
Your OEM gas-selector has 2 small twin venting holes that get exposed to the gas-block vent-channel when you turn it to it's one supposed "suppressed" setting. Also the main hole size exposed to the gasJet path when you turn it over is only about 2/10th of a millimeter smaller than the first. During my R&D and many evolutions of the device, this much restriction change proved to make NO difference at all.

All this being said..

The 2nd setting on my device DOES have a considerable (roughly 20% smaller) orifice size exposed to the gas-jet and some (but not alot) added venting to achieve the effect of reducing gas pressure to your piston.

The 3rd position on the device reduces your orifice size EVEN more and exposes 2 small vent-holes to the vent-channel.

It is valuable to also state that all of the vent-holes (including the front one) on my device are sized exactly the same as your OEM unit's vent holes.


I think the next step in achieving a complete R&D report would be to assemble some kind of a "flow bench" setup on my spare gas block I have laying around.
Put some kid of sealed off air fittings to the barrel bore, install a piston and a 3 select, then apply 120 psi of shop air to see how much force the tail of the piston exerts on a scale or simple spring setup.

Thanks for all the good questions fellas.
 
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