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Mossberg Shockwave / Magpul forend

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/630601935/m/2230032034

September 11, 2017, 06:26 PM
David W
Mossberg Shockwave / Magpul forend
Has anyone done this mod so the Magpul forend will work with the Shockwave?



There is a thread over on arf but photo bucket has done its thing and the pics are gone.


David W.

Rather fail with honor than succeed by fraud. -Sophocles
September 11, 2017, 06:38 PM
SigP239Hokie
Does the standard 590 version of the Magpul forend not fit on the Shockwave?



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September 11, 2017, 06:49 PM
David W
quote:
Originally posted by SigP239Hokie:
Does the standard 590 version of the Magpul forend not fit on the Shockwave?


From what I have been reading no, unfortunately.

Here what Magpul says:

*NOTE: Not compatible with the optional Mossberg heatshield, removal is required before use. Also not compatible with 14" 590 Shockwave and AOW models.


David W.

Rather fail with honor than succeed by fraud. -Sophocles
September 12, 2017, 09:15 AM
SigP239Hokie
quote:
Originally posted by David W:
quote:
Originally posted by SigP239Hokie:
Does the standard 590 version of the Magpul forend not fit on the Shockwave?


From what I have been reading no, unfortunately.

Here what Magpul says:

*NOTE: Not compatible with the optional Mossberg heatshield, removal is required before use. Also not compatible with 14" 590 Shockwave and AOW models.


Bummer, I am sure you did the same googling I did, I suppose a little time on the dremel is the way to go. I wonder if putting a new end cap on would fix the issue?



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September 12, 2017, 08:15 PM
Xer0
I'm guessing that Mossberg is using the shorter tube'd action bar assembly on the Shockwave. On Mossberg 500/590 series, there are two tube length action assemblies, 6 3/4 and 7 3/4. This is the length of the tube that goes inside the front foreend grip. I 'm pretty sure that the Magpul front grip normally fits the longer 7 3/4 tube forends. You can either buy a used 7 3/4 action assembly, or you can buy a Hogue adaptor nut (https://www.midwayusa.com/prod...5-6-3-4-forend-tubes) for around $9. I ran into the opposite problem when I wanted to put wood furniture on my 590A1. I had to buy the shorter tube length action assembly as you can make the shorter tube one work with a Hogue assembly tube extension adaptor in longer foreends, but you can't make the longer one fit the shorter foreends. There is no issue using one or the other on any Mossberg 500/590 series, just one or the other fits different forend grips.

I see new 7 3/4 ones on EBay for around $35.

FYI if you ever experience the safety going on after racking very hard, it's likely the firing pin retaining pin. On mine, it basically got squished to the side and inertia of a hard rack would pushed the firing pin a little past the retaining pin. This would cause the firing pin to stick out the back far enough to impact and engage the safety. It was a real bitch to figure it out too.
September 13, 2017, 07:39 PM
David W
Xer0, thank you, I will order that adaptor nut tonight!

What tool did you use to remove the forend nut? Did you have any tools that would work or did you have to order a Shotgun Forend Removal Tool?


David W.

Rather fail with honor than succeed by fraud. -Sophocles
September 13, 2017, 08:47 PM
wolfe 21
Used a long shank flat blade screwdriver & mallet on my 870. Worked well enough. You can do most of the loosening/tightening by hand.


A Perpetual Disappointment...
September 14, 2017, 07:48 AM
Xer0
quote:
Originally posted by David W:
Xer0, thank you, I will order that adaptor nut tonight!

What tool did you use to remove the forend nut? Did you have any tools that would work or did you have to order a Shotgun Forend Removal Tool?


I bought this cheap one off Amazon several years ago. Works fine and is cheap. https://www.amazon.com/UTG-Del...hotgun+forend+wrench