Thanks guys!

Going to a heavy buffer will help with the recoil but still not to the
extent that controlling the gas will.   The buffer won't reduce the
fouling either.


Most barrels are overgassed from the manufacturer so they can run weak ammo.  


A good example is the DDMK18 that is ported to .070 for the military
since they know the variables that the barrel will see.  That barrel
won't see Tula or Wolf.....For the commercial side, the same barrel is
ported to ~.082.


We take advantage of that big port and use it for an adverse conditions
mode which some departments have found to be handy for running
Simunitions without resorting to buffer/spring changes.


So for a MK18, we have many customers running our block with 3
positions.  Optimal-unsuppressed/suppressed/Adverse ---- .070/.049/.082





I like options.


So now you can run suppressed in 3 different modes - low, med and high.


For unsuppressed you now have a normal and high.





Being able to run at the proper sized port allows you to run longer
before running into a malfunction due to excessive fouling.  


The side benefits apart from a functioning perspective are:


Greatly reduced gas in the face


Reduced recoil


Less of a requirement of having a super strong extractor spring when running optimal gas.


All tuning is done in the upper so no changes to the lower configuration.





If you do run into the situation that you are encountering excessive
fouling and don't have time to clean, you can go up two port sizes when
suppressed and up one size when unsuppressed with no tools or guess
work.



I run an H2 buffer to prevent bolt bounce in full auto.  If you are not running full auto then I'd recommend just an H buffer.  This is all assuming you are controlling the gas.  







Here is a video showing the MK18 running and what it will look like when you are controlling the gas and when you are not.





Here is a relatively recent thread with some guys running the Govnah on their MK18's:

http://www.ar15.com/forums/t_2_543/254317_Govnah_Install_on_DD_MK18_AAR_.html



Let me know if you have any questions.

Thanks!

I have a similar experience.  I think the A5 shines in overgassed configurations and is quite versatile in the various uppers that work with it.

I tinkered with it a bit to see if I could get the A5 to work with the same port sizes I would run for a standard carbine length buffer tube and found that I had to increase the gas port sizes for the A5 system vs the standard carbine length.  If I didn't do that, I had reliability issues in full auto.  I have military and LE customers that don't run the A5 and I would prefer to have upper configurations that are guaranteed to work for those milspec configurations.

One of these days, I may go back to determining optimal port sizes for the A5 system for various barrel length's/gas systems but frankly don't see the need when controlling the gas anyways.  Controlling the gas is more effective and also reduces additional fouling which a buffer system cannot do.



 

As shown in my videos, I am also getting ZERO malfunctions, suppressed and unsuppressed.




Nobody said you NEED optimal performance.   You don't NEED to drive 100 miles on the highway in 5th gear....you could drive that distance in 1st gear the whole time.  1st gear can cover that distance just like 5th gear can so why bother with 5th gear?  I think the answer to that is obvious.  We've done many demo's and the difference to everyone is obvious when running a suppressor w/ regulated gas.  
We strive hard to make products that really work and proving that they really do work.




How do we 'prove' that they work?  For the Govnah:




1.  Full Auto RoF - adding a suppressor typically adds around 200 RPM faster cycling rate.  Suppressors add backpressure which increase the RoF so bringing the port size down brings the system back in balance and RoF will be closer to unsuppressed RoF.  Many don't care about full auto and that is not the point.  The point is that the results can be quantified and shown with a video for people that are not physically present to do a live fire demo.




2.  Gas expelled from the ejection port - while hard to quantify, it is clearly increased and can be seen in videos as seen above and below.




3.  Recoil - at this time, this is best experienced in person.  However, we are working with some folks now to give actual numbers on this for more quantifiable data.




4.  Increased fouling - increased fouling definitely occurs and we have many customers that are extremely pleased at how much cleaner their suppressed AR now runs which allows them to run longer (increasing reliability).




5.  Parts stress - a possibility and makes sense but would be hard to quantify.    As mentioned above, if your extractor spring is a little on the weak side, you will probably have extraction failures when adding the suppressor IF you are not regulating the gas.  I have proven that many times.    So logically, your extractor spring has to work harder if not regulating the gas.  Many don't care about that and just use an O-ring or extra power extractor spring.  I do the latter myself and that is not the point.  The point is that I know the spring isn't working as hard and will most likely never need to be replaced since I am running optimal gas in all modes.
All that said, we know this product is not for everyone.  If none of the 5 points mentioned above are important to you then by all means don't bother with it.  
The biggest issue for most people is that it is not 'automatic'.  Their is a  crowd out there that doesn't want to remember to move the regulator plate to the unsuppressed position when they remove the suppressor.




We have considered designs to 'automatically' adjust the port sizing when a suppressor is mounted but I personally don't like that idea as I would prefer to have control over the gas under all conditions.  Running a 3 position block suppressed, I can go up two port sizes in cases of excessive fouling or adverse conditions.  I personally never had to do that but  some of our customers may run into those kinds of situations.  Likewise, you now have a normal and high for unsuppressed usage as well.  

For proving our barrels:  we offer a sub MOA guarantee at 100 yards using match grade ammo.
 

IME, an H2 buffer, Wolff extra power buffer spring and Wolff extra power extraction spring cures 99% of SBR running issues.

YMMV