I did not have anything to measure the baffles on my 8-stack, but a loaded 357 magnum case (0.379”) will not quite fit in the hole in the baffle. The bullet fits, but it hangs up on the case. These Raptors have replaceable end caps that allow up for larger bores.I think the bore on each can is specific to the caliber ordered. I have the 6 Stack with a 5" reflex on my 300 WSM, and the bore on the blast baffle measures approximately .334"