A new kind of adjustable gas block

[Dolomite_supafly]

http://micromoa.com/

 

It has a plate with two different sized holes in it. The plate moves back and forth depending on the size of port you want.

 

This is pretty neat stuff.

 

Kind of pricey at $150 but all new stuff is.

[mikegideon]

Field adjustable is a biggie. I think the Noveske regulates the gas in a similar way, but the two settings are fixed 

Edited December 18, 2013 by mikegideon

[TripleDigitRide]

Isn't that how the Noveske works? 

Kinda-sorta. But the Noveske Switchblock can't be hidden under the rail, as far as I know. 

Edited December 18, 2013 by TripleDigitRide

[Mark A]

I've been thinking more and more about a custom ar-10 with a longish (20") barrel that I would want to be able to suppress. I see they offer custom plates, how would one know what to tell them to drill them to?

Thanks, Mark

[Guest MicroMOA]

http://micromoa.com/

 

It has a plate with two different sized holes in it. The plate moves back and forth depending on the size of port you want.

 

This is pretty neat stuff.

 

Kind of pricey at $150 but all new stuff is.

 

Thanks for the post!  Note that we do 2 or 3 position.  So you could have one position kill the gas or you wanted to.  Most barrels have their gas ports too large from the factory.  This is a more prevalent issue today than it was 20 years ago when cheap import ammo 223/556 wasn't common like it is today.  Barrel manufacturers know this and don't want to see a return saying their barrel don't work since the port is too small.  

So we take advantage of that larger port.  

Here is how I personally setup my rifles:

For a 3 position, first thing to do is to determine the size of the barrels gas port.  You will need a numbered drill bit set to do this.  Stick the shank of the bit that will fit into the barrel's port.  Then drill out which hole you want to match it.  I like the right port since this is going to be the 'max' gas position.  This will also be the alignment/installation port.

You would then tighten the set screws with the shank of the bit going through the alignment hole, regulator plate and into the barrel's gas port so you know it is perfectly aligned like shown in the picture below:

 

After that is done, I move on to the optimal, unsuppressed position which I like to put on the left position.  With the firearm 'dry' and very little to no lube, I test to determine the port sizes.  So I load 1 round in a mag till the bolt locks back on a single round.  I also load up a full mag and make sure that it will run with the additional resistance applied to the bottom of the carrier from the full mag.

 

I do the same procedure for the suppressed position that I put in the middle except with a suppressor mounted of course.  We like to advise users to put the suppressed position in the middle since it takes more muscle motor control to put the plate in the middle or just use a bullet on each side of the plate to get it in the middle.  We figure if you have time to put on a suppressor then you have time to move the regulator plate in the middle.  Nice thing about this is that if you ever need more gas then pushing left or right will give you more gas.

 

As an example, I have a midlength barrel that came with a huge port from the factory of .089, well it works just fine at .076.  For suppressed, I used .055.  So that is my 3 settings for that rifle.  I can run it at .076 un-suppressed and if it ever gets dirty, I can just increase the gas port size to the same port as the barrel rather than taking the time to stop and clean it. 

Likewise, when running suppressed at .055, I can always go up to .076 and then to the max of .089.

 

Manufacturer port sizes vary all over the place, see my link here discussing testing of 3 different 10.5" barrels from 3 different manufacturers all with widely varying port sizes: http://micromoa.com/?page_id=855

All testing with the same ammo, lower and BCG.  The bore diameters vary and in result port sizes vary.  So it is nearly impossible to figure out the 'optimal' port sizes for anyone without actually shooting the actual barrel.

Of course we can just guess which is why we do offer some pre-determined / pre-drilled plates.

 

In that article above, our pre-determined port sizes would have worked for 2 out of 3 of those barrels but would have been too small for the 3rd one.  Good thing is you just drill it out till it works....much easier to remove than add metal.

 

It is hard to try to please everyone which is why we do some pre-determined/pre-drilled 2 position plates as well as offer custom 2 and 3 position plates.

 

In regards to the price:

First look around and see the other 'tool less' options and you will see this is actually the lowest priced.  The other 'tool less' options like the Noveske or WAR upper are priced higher and both use non-standard gas tubes and are not modular.

This is also the only 'tool less' option that uses a standard UN-modified gas tube.

It is the only 'tool less' option that gives you the flexibility to have an optimal and adverse mode.  The other tool less options are off/suppressed/unsuppressed or suppressed/unsuppressed...so basically full gas.  We can do all that and add in an optimal setting since most barrels are over-gassed...since we are a max of 3 positions you would have to give something up to have this which I think should be the off...but you can always swap plates if you change your mind.  We think if you need more than 3 settings it becomes too confusing and too much to remember.  If you want more settings then maybe a set screw block is more for you.

It is also the only one that is modular.  With the modular plate design, it can handle any gas system length and any caliber with a simple plate swap...however we only have .750 gas seat blocks right now.  We are coming out with .625 diameter.

We are considering doing diameters larger than .750 but that would require a proprietary straight gas tube and reduce rail compatibility as well so we haven't been too keen on doing it but haven't shelved the whole design either.

 

Please visit my site for more information/pics/videos: http://micromoa.com

 

Thanks for the interest!

Edited December 18, 2013 by MicroMOA

[Dolomite_supafly]

For those of you wondering, I am not affiliated with Micro Moa and was just posting something I ran across.

 

Second, a word of caution to Micro Moa. Do no advertise here. We require all commercial entities to become a vendor before they advertise here. I see no problem with linking something I have already linked but please do not advertise.

 

And finally, most of you will see I have been saying the same thing for a very, very long time about over gassed guns and the need for an adjustable gas block.

 

I do have a question though. Heat kills springs, it is a fact. The gas block does get extremely hot during firing, especially so with FA or faster firing rates, and that heat has to be transferred to the spring. So how do you mitigate the heat transfer to the spring in the gas block or does it even affect the springs performance?

 

This is a very ingenious way to solve a problem. I might have to look at it for my 300 Blackout when I SBR it.

 

Do you plan on making a version that clamps to the barrel rather than set screw to the barrel? I prefer the clamp version as I have seen some setscrew versions have issues with coming loose. I have also read that the setscrews on some blocks not lining up with the dimples in some barrels.

[mikegideon]

For those of you wondering, I am not affiliated with Micro Moa and was just posting something I ran across.

 

Second, a word of caution to Micro Moa. Do no advertise here. We require all commercial entities to become a vendor before they advertise here. I see no problem with linking something I have already linked but please do not advertise.

 

And finally, most of you will see I have been saying the same thing for a very, very long time about over gassed guns and the need for an adjustable gas block.

 

I do have a question though. Heat kills springs, it is a fact. The gas block does get extremely hot during firing, especially so with FA or faster firing rates, and that heat has to be transferred to the spring. So how do you mitigate the heat transfer to the spring in the gas block or does it even affect the springs performance?

 

This is a very ingenious way to solve a problem. I might have to look at it for my 300 Blackout when I SBR it.

 

Do you plan on making a version that clamps to the barrel rather than set screw to the barrel? I prefer the clamp version as I have seen some setscrew versions have issues with coming loose. I have also read that the setscrews on some blocks not lining up with the dimples in some barrels.

 

I'm dipping my toe in the water with adjustable gas on the Grendel build. I won't have wildly varying pressures, and am doing it just to tune the gun. It will be a standard JP block mounted outside the handguard.

 

There's lots to like about the MicroMOA block.

[Guest MicroMOA]

For those of you wondering, I am not affiliated with Micro Moa and was just posting something I ran across.

 

Second, a word of caution to Micro Moa. Do no advertise here. We require all commercial entities to become a vendor before they advertise here. I see no problem with linking something I have already linked but please do not advertise.

 

And finally, most of you will see I have been saying the same thing for a very, very long time about over gassed guns and the need for an adjustable gas block.

 

I do have a question though. Heat kills springs, it is a fact. The gas block does get extremely hot during firing, especially so with FA or faster firing rates, and that heat has to be transferred to the spring. So how do you mitigate the heat transfer to the spring in the gas block or does it even affect the springs performance?

 

This is a very ingenious way to solve a problem. I might have to look at it for my 300 Blackout when I SBR it.

 

Do you plan on making a version that clamps to the barrel rather than set screw to the barrel? I prefer the clamp version as I have seen some setscrew versions have issues with coming loose. I have also read that the setscrews on some blocks not lining up with the dimples in some barrels.

 

Just so I understand, it is ok for me to respond to questions.  I just can't create any new threads trying to sell my block right? 

 

In response to your questions, yes, we were very concerned with the possibility of heat destroying the spring.  The initial prototypes used a compression spring which failed from torture testing and it was harder to swap plates with that design.  The current torsion spring design can handle a lot higher temperatures and you will notice that it is somewhat exposed for cooling. 

 

You can see in the link below that we fired (4) 45 round mag dumps with no issues with the regulator getting stuck.  All corrosive ammo in 5.45 out of an 8" barrel.  You can see more links to the testing.  Around 2k rounds were fired all in full auto doing 45 round mag dumps with no spring issues or any other issues for that matter.

I have other customers that have put over 10k through it in full auto suppressed and un-suppressed with no issues.

http://www.youtube.com/watch?feature=player_embedded&v=mKMZTjEXbw0

http://micromoa.com/?page_id=714

 

We have never had any issues with the set screws coming loose.  We also purposely offset the first set screw so we don't go in some other manufacturer's dimple on the barrel since they are not as concerned with alignment as we are. 

 

We are looking into the possiblity of a clamp on but not sure when as we have very little demand for that.

 

Thanks!

[KKing]

This would be a great piece of equipment for the 300BO upper I'm planning for early next year.... suppressed, of course. Unfortunately, I only run clamp on gas blocks due to past experience with set screw to the barrel types, which in my opinion is an inferior design engineering wise. If they make a clamp on, I'd more than likely be a customer

[Ted S.]

I'm dipping my toe in the water with adjustable gas on the Grendel build. I won't have wildly varying pressures, and am doing it just to tune the gun. It will be a standard JP block mounted outside the handguard.

 

There's lots to like about the MicroMOA block.

 

On my build, the barrel I have on order is .875, so the MicroMOA is out of the question at the moment for me. (Unless they begin to manufacture in that size). I'd like to get gas block for it in case I am wanting to run a silencer in the future, but also as a hedge against possible overgassing like what is happening on my current rifle.

 

Hopefully won't have to worry about overgassing since the barrel is longer. :x: