Something to think about...
and that is gas flow and pressure in a suppressed vs. a non-suppressed firearm.
A 6920 without suppressor functions well without it. With one mounted--and no further modifications--you will batter and beat the inner parts very badly, and parts life will be limited, indeed.
Solution: There are two. Either have a adjustable gas block mounted, or buy a purpose-built rifle with the proper sized gas port to function normally with the suppressor.
I'll add that most commercial guns are way over-gassed to begin because they're designed to feed reliably with the lessor amount of gas that is generated with lower power commercial rounds (steel is notoriously under-powered). So indeed, add a suppressor and you can get a lot more gas than is necessary to reliably cycle the action.
I run a Kestrel 5.56 on a my AR, and have been able to manage the extra gas pressure by simply switching to a full auto bolt carrier group and a heavier buffer. The extra weight has been more than sufficient for my purposes, and has at the same time kept my rifle still functioning reliably when not running the can. I ran 800 rounds through my AR this August-September, and the heavier buffer and BCG worked great. I've got a number of friends who also run suppressors, and we've all managed to avoid the adjustable gas block by going to heavier buffer and bolt carrier group route.