Can you convert Shockwave to full size shotgun?

wild cat mccane · June 20, 2017, 05:03 PM

Hi there,

If you pick up a stock and replacement barrel, could you convert the Mossberg Shockwave to a full sized shotgun?

jaguarxk120 · June 20, 2017, 06:44 PM

Chances are you can fit a full sized stock and barrel, BUT and that is a big BUT.

The pistol grip and barrel go with the gun (receiver), that pistol grip and 14 inch barrel were fitted to the receiver at the factory. You can not fit the pistol grip and barrel to
another receiver.
Also your state may have laws about short barreled shotguns.

Targa · June 20, 2017, 06:54 PM

Why would you? Not being a smart #%^, just wondering.

GarandTd · June 20, 2017, 07:41 PM

I cannot speak for the legality of such a conversion, but mechanically speaking, sure. It's a Mossberg and should accept any Mossberg stock or barrel as long as the mag tube is compatible.

wild cat mccane · June 21, 2017, 08:18 AM

I don't understand the confusion.

I am asking if someone picked up a $20 stock and a normal sized 590 barrel, could you essentially have an off the rack Mossberg 590 by converting the Shockwave.

Why? Cause the cost would be minimal if possible/legal.

Targa · June 21, 2017, 08:24 AM

Gotcha....2 for 1 at a better price point, makes sense.

Jim Watson · June 21, 2017, 08:58 AM

I understand that the Shockwave is in kind of a gap in the regulations.
If you put a regular stock and barrel on it, you have a regular shotgun.
I am not sure that it would be legal to return it to the short form, that MIGHT be considered building a SBS. I think Thompson Center had to get an exemption to allow back and forth exchanges between pistol and rifle configurations of Contenders.
I don't know but you should find out before swapping parts.

FITASC · June 21, 2017, 09:01 AM

Would the possession of the short barrel not on the legal Shockwave without a stamp be an issue then?

T. O'Heir · June 21, 2017, 11:44 AM

Only issue would be where the take down screw assembly is located. Isn't in the same place on longer barrels.
The Shockwave is about as useless as useless gets anyway. Any shotgun with no stock is a Hollywood inspired marketing toy.

Blindstitch · June 21, 2017, 01:01 PM

I think you're going to run into the issue of putting a stock on a pistol and therefore shouldering it to shoot would become "illegal" or whatever those Ar15 pistol guys with sig arm braces have been saying for a while.

But since most people expect to see a stock on a shotgun nobody would suspect that it's really a pistol. I'm sure there's a marking on it that identifies it as a pistol even if it's a variation of like how the Mossberg 500A/500B... could even be 590P. Then you have to worry if the tube and barrel connection are the in the same spot as the 590.

Sounds like a waste of money building a pistol into a shotgun unless you have a free barrel and stock sitting around. And maybe some legal council.

Bill DeShivs · June 21, 2017, 02:40 PM

Now- here's the real answer-
Yes-you can convert a Shockwave to a full-sized shotgun.
However, you CAN NOT convert that full-sized shotgun back to Shockwave configuration. The Shockwave and similar guns are not "pistols," they are "firearms."
The criteria for the "firearm" designation requires that the receiver never had a full-length stock attached.
You can, however convert the gun to standard 18" bbl. & 26" OAL configuration.

hoghunting · June 21, 2017, 03:37 PM

Quote:

Originally Posted by T. O'Heir

Only issue would be where the take down screw assembly is located. Isn't in the same place on longer barrels.
The Shockwave is about as useless as useless gets anyway. Any shotgun with no stock is a Hollywood inspired marketing toy.

Guess Clint Smith at Thunder Ranch didn't realize the Shockwave was useless.

https://www.youtube.com/watch?v=fM_sqSTg2v8

June 20, 2017, 05:03 PM	#1
wild cat mccane Senior Member Join Date: May 22, 2011 Posts: 3,623	Can you convert Shockwave to full size shotgun? Hi there, If you pick up a stock and replacement barrel, could you convert the Mossberg Shockwave to a full sized shotgun?

June 20, 2017, 07:41 PM	#4
GarandTd Senior Member Join Date: June 15, 2016 Location: Rural PA Posts: 1,639	I cannot speak for the legality of such a conversion, but mechanically speaking, sure. It's a Mossberg and should accept any Mossberg stock or barrel as long as the mag tube is compatible. __________________ 22lr, 20 gauge, 8mm Mauser, 35 Remington, 30-06, 5.56x45/223, 9mm, 380acp

June 21, 2017, 09:01 AM	#8
FITASC Senior Member Join Date: December 6, 2014 Posts: 6,441	Would the possession of the short barrel not on the legal Shockwave without a stamp be an issue then? __________________ "I believe that people have a right to decide their own destinies; people own themselves. I also believe that, in a democracy, government exists because (and only so long as) individual citizens give it a 'temporary license to exist'—in exchange for a promise that it will behave itself. In a democracy, you own the government—it doesn't own you."- Frank Zappa

June 21, 2017, 11:44 AM	#9
T. O'Heir Senior Member Join Date: February 13, 2002 Location: Canada Posts: 12,453	Only issue would be where the take down screw assembly is located. Isn't in the same place on longer barrels. The Shockwave is about as useless as useless gets anyway. Any shotgun with no stock is a Hollywood inspired marketing toy. __________________ Spelling and grammar count!

June 21, 2017, 01:01 PM	#10
Blindstitch Senior Member Join Date: April 14, 2013 Location: Milwaukee, Wisconsin Posts: 2,692	I think you're going to run into the issue of putting a stock on a pistol and therefore shouldering it to shoot would become "illegal" or whatever those Ar15 pistol guys with sig arm braces have been saying for a while. But since most people expect to see a stock on a shotgun nobody would suspect that it's really a pistol. I'm sure there's a marking on it that identifies it as a pistol even if it's a variation of like how the Mossberg 500A/500B... could even be 590P. Then you have to worry if the tube and barrel connection are the in the same spot as the 590. Sounds like a waste of money building a pistol into a shotgun unless you have a free barrel and stock sitting around. And maybe some legal council. __________________ NRA Lifetime Member

June 20, 2017, 06:44 PM	#2
jaguarxk120 Senior Member Join Date: February 28, 2008 Location: Michigan Posts: 2,619	Chances are you can fit a full sized stock and barrel, BUT and that is a big BUT. The pistol grip and barrel go with the gun (receiver), that pistol grip and 14 inch barrel were fitted to the receiver at the factory. You can not fit the pistol grip and barrel to another receiver. Also your state may have laws about short barreled shotguns.

June 20, 2017, 06:54 PM	#3
Targa Senior Member Join Date: March 20, 2014 Posts: 2,084	Why would you? Not being a smart #%^, just wondering.

June 21, 2017, 08:18 AM	#5
wild cat mccane Senior Member Join Date: May 22, 2011 Posts: 3,623	I don't understand the confusion. I am asking if someone picked up a $20 stock and a normal sized 590 barrel, could you essentially have an off the rack Mossberg 590 by converting the Shockwave. Why? Cause the cost would be minimal if possible/legal.

June 21, 2017, 08:24 AM	#6
Targa Senior Member Join Date: March 20, 2014 Posts: 2,084	Gotcha....2 for 1 at a better price point, makes sense.

June 21, 2017, 08:58 AM	#7
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,535	I understand that the Shockwave is in kind of a gap in the regulations. If you put a regular stock and barrel on it, you have a regular shotgun. I am not sure that it would be legal to return it to the short form, that MIGHT be considered building a SBS. I think Thompson Center had to get an exemption to allow back and forth exchanges between pistol and rifle configurations of Contenders. I don't know but you should find out before swapping parts.

June 21, 2017, 02:40 PM	#11
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 10,981	Now- here's the real answer- Yes-you can convert a Shockwave to a full-sized shotgun. However, you CAN NOT convert that full-sized shotgun back to Shockwave configuration. The Shockwave and similar guns are not "pistols," they are "firearms." The criteria for the "firearm" designation requires that the receiver never had a full-length stock attached. You can, however convert the gun to standard 18" bbl. & 26" OAL configuration. __________________ Bill DeShivs, Master Cutler www.billdeshivs.com