Bloggo no likee recoil

I recently bought a Hogue overmolded shotgun stock which has the Knoxx recoil reduction system in its innards.



Hogue no longer lists this item in their catalog, which may be because Blackhawk now owns the Knoxx stock company - see their web page here. I got this thing used but almost new, and yesterday I gave it a whirl at the range. I mounted it on a Remington M870 that's pretty basic - 20 inch stock factory barrel with rifle sights, Mesa tactical sidesaddle and a sling. The Knoxx stock has the same dimensions as the Speedfeed unit I took off of it, though I wish it was a bit shorter.
I compared the firing characteristics to a Mossberg M500 that I've had for a long time - factory ghost ring sights, an 18.5 inch barrel, sling and TacStar sidesaddle. It's been through a couple of classes with me, is stone reliable and is close enough in size and weight and stock geometry to the M870 to be a reasonable type for comparison.
I fired 4 rounds of Fiochhi plated 00 buckshot through each gun. The difference between them wasn't remarkable, with the M870 seeming to have a slightly reduced impulse. It was hardly enough to make a scientific comparison, but time was tight and I only had so many rounds of the same type on hand that I could afford to use up. I'll do this again and fire more ammo next time, but for now I can say that the Knoxx system seems to work though not as dramatically as I'd thought it might.