It would seem to be helpful if using the "push-pull" technique to control recoil.

Mossberg seems to have copied it from Serbu for use on their Compact Cruiser AOW's.

 

http://www.mossberg.com/category/series/compact-cruiser-aow/

 

 

I believe that ATF ruled you can't put a vertical grip on a shockwave, similar to a handgun.

13 minutes ago, PK90 said:

I believe that ATF ruled you can't put a vertical grip on a shockwave, similar to a handgun.

Do you know if that was in a formal letter like the original approval?

Serbu markets the whole pump handle assembly to the shockwave market.

"Made by Serbu Firearms from both Remington/Mossberg parts in addition to our own manufactured parts. Compatible with either Remington 870 shotgun or Mossberg 500/590 (including shockwave models)."

https://serbu.com/collections/super-shorty-accessories/products/serbu-pump-handle-cocking-slide-assembly

The Black aces has a vertical grip (as well as a brace) and it is NJ legal.

http://store.rtsponline.com/black-aces-tactical-black-aces-tactical-pro-series-11091546.html

The Serbu grip, although it looks cool, makes it more uncomfortable to shoot.  

1 hour ago, Ray Ray said:

The Serbu grip, although it looks cool, makes it more uncomfortable to shoot.  

Recoil wise or more difficult to aim? You are right on the cool factor though; Mossberg must have gotten tired of Serbu making money with their Super Shorty based on the 500 platform and just created their own version in the compact cruiser aow's.   

4 hours ago, samtechlan said:

Recoil wise or more difficult to aim?

Both

Your hand doesn't fall on the forend naturally so it feels awkward.  Aimming is subjective, but verticle foregrips on pump guns suck.

1 hour ago, Ray Ray said:

Both

Your hand doesn't fall on the forend naturally so it feels awkward.  Aimming is subjective, but verticle foregrips on pump guns suck.

I think you are right, I tried to imagine racking the pump using the strap as a makeshift vertical grip on my shockwave and the angle felt all wrong.  I think it has to do with the fact that the shockwave grip is more or less horizontal and it makes for some very awkward mechanics with a vertical foregrip.

All that being said it seems that a vertical grip would make much more sense on a super compact with no stock and a traditional pistol grip like the Serbu or the Mossberg Compact Cruiser.  Here the two grips would be complementary.    

 

 

arms / Compact Cruiser® AOW

500 Compact Cruiser AOW

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