This was a list put together and pulled from another site but should help get you closer to a decision.
KAK Industries 11" bbl with carbine gas is .084 - .086"
Mega Arms 10.5" bbl with carbine gas is .080"
Green Mountain 10.5" bbl carbine gas is .087"
Anderson 10.5" bbl carbine gas is .086"
Ballistic Advantage 11.5" bbl carbine gas is .073"
Ballistic Advantage 10.3" Hanson bbl carbine gas is .076"
Ballistic Advantage 10.5" bbl carbine gas is .078"
Aero Precision 10.5" bbl carbine gas .0785"
Faxon 10.5" Gov't/Socom bbl with carbine gas is .080"
Faxon 11.5" Big GUNNER bbl with mid-length gas is .110"
LMT 10.5" bbl with carbine gas Crane spec'd at .070"
PSA 10.5" bbl with carbine gas is .081" - .089"
Integrity Arms 10.5" bbl with carbine gas is .085"
Sionics RGP 11.5" bbl carbine gas is .063-.068 "
And this :