Remington’s upcoming VERSA MAX shotgun features a new self-regulating gas system called Versaport.
Versaport works simply enough: multiple gas ports are so far forward that a 3.5″ shell will block most of them, a 3″ will block some and a 2.75″ shell will block none. This allows a greater percentage of gas from the low powered shell to operate the piston and restricts the gas from higher powered shells. Simple but effective. This video explains it.
Remington has also posted a video briefly showing the VERSA MAX shotgun in use …
Tamarack Tactical has posted more videos showing the shotgun in action.