I could talk more, but I wont!!!

I had this done on my Mossberg 590A1, but I know factually they do it for the Remington 870 also!
I had sent my barrel and had it back in just over a week, granted I sent it priority mail and it got there in two days...
The VCS involves lengthening the forcing cone to create a choke in an otherwise cylinder bore barrel, back boring which smooths out the changes from chamber to muzzle to make a smoother transition for the shot, helping it to retain the pattern density, and most visibly, the porting!
I wanted to show in the video how the muzzle climb and perceived or felt recoil is reduced by the VCS work. I was shooting full power loads as well as low recoil. Its visible how there is little muzzle climb at all while shooting several different buckshot loads!
I shot;
Federal Premium Tactical, (LE132)
Hornady TAP
Winchester Super X
Winchester Ranger
Remington SP Duplex BB
Here is another video I did when the sun went down, you can see how the porting work to vent gases upwards rather than straight out in front of the muzzle! In the video I also used Federal Premium PowerShok rifled slugs, and Federal Tactical TruBall.