Going to a heavy buffer and/or stronger spring will help with the recoil but still not to the
extent that controlling the gas will. Stronger buffers/springs 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.
So for a MK18, we have many customers running our block with 3
positions. Optimal-unsuppressed/suppressed/Adverse ---- .070/.049/.082 for running milpsec ammo or .073/.052/.082 for commercial ammo.
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.
You will know what setting the block is in by looking at it or by feel in complete darkness unlike a set screw adjustable block.
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.
Video below shows the same configuration shot unregulated vs regulated at 480FPS and you can clearly see the difference in cyclic rate, excess gas from ejection port and if you look carefully enough - the increased recoil:
![](http://www.ar15.com/lib/editor/img/trans.gif)
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.
![](http://www.ar15.com/lib/editor/img/trans.gif)
Here are some threads with discussion/feedback:
http://www.ar15.com/forums/t_2_543/254317_Govnah_Install_on_DD_MK18_AAR_.htmlhttp://www.ar15.com/forums/t_2_543/258195_MK18_and_Govnah_specs.htmlhttp://www.ar15.com/forums/t_6_51/434141_Any_kind_of_tuning_needed_for_reliable_SBR_.htmlhttp://www.ar15.com/forums/t_6_20/438158_Are_adjustable_gas_blocks_needed_for_5_56_.htmlBTW, we are expecting another batch to be back from black oxide this Thursday.
Thanks!
micromoa.com