I have a 20" Shilen with rifle length gas system. I bought an adjustable gas block and have a few extra buffers. My opion your rifle will be fine with the rifle length buffer and spring using a standard carrier. I'm using a CAR stock, buffer, spring with M-16 carrier. I had to open my gas block almost all the way out when new and has never needed further adjustment. With the adjustable gas block my 20" 6.5 Grendel is a very smooth shooting rifle with mild recoil. I'm not running any muzzle device.
If I had to do over again I would not have bought an adjustable gas block for my 20" 6.5 Grendel. I really think the rifle gas system is about optimum with the 6.5 Grendel. You could always call Mark at PF and ask his advise but I really don't think'll you'll need an adjustable gas block.
If I had to do over again I would not have bought an adjustable gas block for my 20" 6.5 Grendel. I really think the rifle gas system is about optimum with the 6.5 Grendel. You could always call Mark at PF and ask his advise but I really don't think'll you'll need an adjustable gas block.