Oh those pesky buffer tubes.
I have been wondering how bad the "gassing" around the charging handle is from the .300 blackout when used with a suppressor.
I watched a friend test fire his M4-2000 on his 10" 5.56 Noveske. The gas leak around the handle (no it isn't a gas-buster, he has ordered one) seemed pretty bad.
Stopping power: The power some guns have to make you stop what you are doing and get your wallet out.