BudsGunShop.com - Ported Barrels

in most cases the porting on a shotgun was just not worth it they make the gun louder and there is no measurable effect on recoil

Porting is generally to compensate for muzzle rise. I'm sure they saw little to no benefit in the porting and chose to save the extra step and money to port the barrels. We are talking shotguns here not large caliber pistols or precision rifles. Porting would be beneficial for those types of firearms.

Porting barrels was done to keep the wad from destroying dense tight patterns (the wad being lighter would get popped by the gases through the shot pattern so releasing the gas before the was exited improved patterns). With the advances in shot shell performance it is not necessary and if you need ports you can get it in a ported choke.

Christopher, I would imagine to lower production costs. Mossberg will be the best source for the reason at Tel: (203) 230-5300 | 8:00am-4:30pm Eastern or by email inquiry here : mossberg.com/contact-us/