I am a huge fan of adjustable gas blocks and have then installed on nearly every AR15 and AR10 format rifle I own. I maintain that an adjustable gas block is the single most impactful upgrade you can make on any AR15. It is my opinion that an adjustable gas system will do more for you than any other single upgrade you can add on an AR15 with less recoil, faster shot follow up, less shooter and part fatigue, cleaner operation, and altogether a better shooting experience than you have ever experienced. Why? Simple; nearly every AR15 is severely overgassed to assure part interoperability reliability. The result is the gas port on the barrel ends up being oversized, the gas block hole is oversized to assure alignment issues are not a problem and now we have way more red hot gas being blasted back into the action to cycle everything than realistically needed. To counterbalance this, we have gone to heavier M16 carriers, H2, H3 heavy buffers and even in some cases heavier buffer springs. Then answer to this engineering challenge is an adjustable gas block to bring everything back into equilibrium.
My original All About Adjustable Gas block article has been one of my most popular articles to date and luckily it has grabbed the attention of a few manufacturers who noted that they should not be left out. One of those newcomers is MicroMOA who offers a very unique designs unlike anything else on the market.
Two of the biggest challenges with any gas block, including adjustable version, is that they can on rare occasion become clogged during full auto fire or fall out of adjustment. For those adjustable gas blocks without a detent securing the adjustment screw, full auto fire from an M4/M16 can literally shake the screw loose. MicroMOA adjusts gas pressure via orifices on a steel plate which slides and clicks in two or three positions, depending on the plate used. This unique adjustment method can never go out of adjustment while still allowing for adjustment.
THE MICROMOA CONCEPT
Over the years, I have had many emails and comments asking what about reliability as gunk and round count builds up. Assuming you appropriately back off the tuning of an adjustable gas block by ½ turn after you just get the bolt to lock back, I have never had an issue. That noted, I can see where extreme environments or too light of an adjustment setting may cause blockages and that is where I really like the MicroMOA Govnah gas Regulation System.
Typical AR Adjustable gas blocks are basically a screw that restricts the flow of gas at the gas block into the gas tube much like a spigot restricts water. If you have it tuned just barely over functional requirements as many 3Gunners do, build up can throw everything off. In most cases, the worst thing I have ever seen is that cycling still occurs but the bolt does not lock back. So the question is that if we are switching between a very low suppressed gas setting, to a medium/optimal regular setting, to a full open harsh environment setting, how do we go about that consistently. Generally that means counts rotations or clicks with an adjustment requiring a hex key. MicroMOA has an easy and simple solution. If you want the ability to swap to different gas regulation setting on demand, the patented MicroMOA Govnah Gas Regulation system is your only option that allow instant swaps back and forth between settings.
MicroMOA’s idea of gas regulation aligns with all the testing I have done over the years. “IF” you have the right setting it should not change.. ever. Tuning is a one way street. Increase the gas pressure/port size until the bolt locks back on the last shot with your lowest powered rounds and then increase by one full turn. Lets say you had to drill your own gas port in the gas block. In that case you would slowly move from the smallest drill bit you had to the largest until you found the port size that locked back the bolt and then go up one more drill size to assure reliability. This is essence what MicroMOA has done with plate that slides back and forth in the gas block. Position 1 detent one can be an optimal port setting and Position 2 detent can be a wide open port for harsh environment reliability all you need to do is slide the plate back and forth with a bullet poked through the handguard or you can make up your own combination. No twiddling with Hex wrenches needed.
The MicroMOA gas blocks were tested on the MMC Armory Recon |
FIT, FINISH, FEEL, FEATURES, & FUNCTIONS
MicroMOA can provide their Govnah gas block equipped with either a plate with typical orifices in a variety of configurations or a drill-your-own version like the ones I picked up. The Drill-your-own option requires tuning which entails bringing a set of small drill bits and a cordless drill to the range and following a standard gas block tuning process. This process is - drill a hole in the plate starting with your smallest drill bit (usually 1/32") load a single round in the magazine and fire. If the bolt locks back, rejoice, otherwise pull the detent retainer spring back on the gas block, pop out the plate, widen the hole by going up one drill bit size, pop the plate back in and repeat the tuning process until the bolt locks back. Once this is complete, you have a hard tuned gas block setting customized to your AR15 which will never come loose or loose adjustment.
Obviously having a two or three position plate allows for multiple gas adjustment options. MicroMOA recommends tuning one port position for the best soft competitive shooting performance and drilling the other position wide open for defensive applications from the same gun. If you have a supressor, the third plate position can offer an even lower gas adjustment due to the increased back pressure from a supressor. I do not own suppressors, so I like setting up the three position plate to be optimized on the center position and wide open on the left and right positions. If I ever do run into a reliability issue or want to assure total reliability for defense, all I need to do is push the slide with a bullet tip from either side to have my AR15 in a high reliability mode with wide open gas pressure.
If you were going to install a gas block on a machine gun, the MicroMOA Govnah would be the one simply because it is the only adjustable gas block which is full auto rated. The Govnah is also a solid steel beast of a gas block compared to any other gas block in existence. The Govnah was not designed to be light, but it was designed to handle the most brutal environments on the planet.
MicroMOA also has another very interesting $20 "adjustable" drill-your-own gas block model called the Baby Govnah. It is actually more of a hard tunable gas block than being considered "adjustable". Basically this is a low profile gas block without the gas port drilled, so it gives the owner the ability to drill whatever gas orifice size they need. Obviously, the tuning requires the removal of the gas block to drill out and tune the gas block between each testing/tuning cycle is painful, the process guarantees that the adjustment will stay exactly where you left it. For those with the patience for the process, the Baby Govnah is a very inexpensive option to get the gas properly related on your AR15 and an option which delivers.
FINAL THOUGHTS
I am excited we are seeing more entrants into the adjustable gas block market. I continue to believe that an adjustable gas block remains the most important upgrade you can make to your AR15. There is no other single upgrade which can net more advantages to the shooter with softer recoil, less parts fatigue, cooler running bolt carrier group, cleaner running, a flatter shooting rifle, and faster follow up shots. Above all other upgrades I recommend an adjustable gas block, and MicroMOA has believed a few new innovative options which we can choose from in the market that give you permanent adjustments which will never fall out of adjustment.
SPECS
Govnah - MicroMOA has 2-position and 3-position plates that can be slipped into their gas block available in pre-set port based on in house testing or the drill-your-own options. I choose the 3-position drill-your-own option - $149
Baby Govnah - The Baby Govnah is pure and simply a drill-your-own gas block. - $20
SOURCES
MicroMOA - http://micromoa.com/