Originally Posted By: RayDog
True for bolt guns but with an DI host how you control the gas is very important. Best to have a smaller than normal gas port for best suppression at muzzle as well as shooters ear. With a normal size gas port the better you suppress at the muzzle the more you will see shooters ear numbers go up, as well as increased bolt speed, blowback ect. A 30 cal can on a 204 AR10 with normal sized port will sound better than a dedicated 22 can to the shooter.
I can see the increased bolt speed with an increased amount of back pressure due to a more effective suppressor.
Which is what I would highly suggest to the OP. For a hunting application, you want optimal sound suppression at the point towards target. The amount of db's changed if any at your ear are not going to be enough to be drastically different between a 30 and cal specific. Say you are increasing a db or 2 at the action, and gaining 3-5 at the muzzle, IMHO the Pro outweighs the Con.
Go caliber specific if you want the absolute best performance, Sometimes running a can with the aid of more back pressure increases the performance of an AR. It has on a couple of my AR10's.