From Silencerco who is using my 77/44 (44magnum rifle 17.5" barrel)
I'm still trying to get confirmation on my Osprey, but it looks good for 44magnum in rifle platforms.
The factory ammo we had was not very hot however it didn't stress the Octane a bit. It stayed cooler than I expected as well. In limited numbers I think you will be just fine running 44 mag through it
I'm still trying to get confirmation on my Osprey, but it looks good for 44magnum in rifle platforms.