Winchester Model 12 Compensator
I recently picked up a few guns including a Winchester Model 12 in 16 gauge, 2 3/4" with a rib and compensator. I've learned a bit about the gun itself, including the "it's not broken" feed system. The gun also carries a compensator and I can find nothing about it on line. I don't know if it's a Cutts model or Lyman or if either, what model it is or how to adjust.
Rather than straight cuts on its side this uses a series of "V" shape on each side of the barrel. There is a knurled lock ring at the barrel and the muzzle of the device. The barrel stops at the start of the cuts and then starts again where the cuts end. I'm assuming the shot column and wad don't open up in that space.
Any idea regarding make or model and how to adjust? I assume Winchester didn't attach these at the factory and is aftermarket, yes?