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20ga. Shockwave Transition to a 20ga. 590?

I

insinkerator

Copper BB
I live in California (would leave if I could) and have an opportunity to get a Mossberg Shockwave 20ga for free from an out of state family member who owns one.

From my research I am convinced that the 20 ga. Shockwave is not legal in California.

The Shockwave is basically a Mossberg 590, based on my research. The Mossberg website lists a 20ga 590 with 18.5 inch barrel and full stock. Mossberg 590 7-Shot

My primary question for the forum is, is it reasonable to expect parts (barrel and stock) from the 590 to be exchangeable with the Shockwave? Obviously the intent here is to modify the Shockwave out of state and bring into California as a regular model 590 long gun/shotgun, and leave it that way.

I know there are probably legal issues about my intentions and am happy to hear those kinds of comments from the forum, but my real interest with this post is simply understanding part interchangeability.
 
While what you're asking is likely doable I think you would be better off selling the Shockwave in the state where it resides and buying a 590 replacement.

In today's market place parts, especially non 12 gauge parts, are sometimes hard to find and you will likely have more money invested in parts than simply buying a weapon.

Non 12 gauge barrels have been extremely hard to find of late.

A used (or new) Mossberg 590 can be found through local dealers and certainly on the internet. If you're open to other options both the Mossberg 500 and Mavrick 88 are excellent weapons and less expensive.

The other thing to consider is that a Shockwave is not designated as a "shotgun" and there would be legal question that need to be researched before modifying it.

Regards
 
100% not an expert, but if I recall from previous posts from shockwave owners in California, the question isn't the gauge but the barrel length. Most Shockwave’s are fitted with a 14” barrel while California requires an 18” barrel minimum. It’s not a question of which type of grip or a stock, just the barrel length. If the gun in question has the 18”, logically it should be legal because it would then be a regular shotgun with a birds head grip. If it has a 14”, then it would be a true Shockwave and wouldn’t be kosher. It would seem that you would just need to find a 20g barrel 18”+ to be golden.
 
Just a point of reference -- a brand new Maverick 88 in 20 gauge is going for between $220 and $240 almost everywhere and if you catch a sale you can typically pick one up for around $200. And these are excellent weapons.

Regards
 
Thanks for the comments about alternate models, the family member is having some cash problems and I'm trying to help out by relieving them of some firearms, just don't need to go to jail to do it. If I were going to acquire a new weapon myself I would do exactly as some of you have recommended.

Rodburner, I was thinking the same thing, Mossberg has a California compliant 12 ga. Shockwave that has the same grip as the 20ga. (has the 18.5 barrel). So I'm with you on really only needing the barrel. If you believe the Mossberg website they list the 18.5 barrel for $125, assuming it is ever really available.

Hard to say if this deal will go anywhere, just collecting data now and appreciate the comments.
 
Make sure you check the required magazine tube length for using an 18.5 inch barrel. I suspect you will also need to change out the magazine tube and spring.

I somewhat remember a discussion about four years ago regarding the legal aspects of converting a Shockwave to a conventional shotgun. If I remember correctly you can do a one way conversion but once that is done you can not legally convert it back to the original Shockwave configurtion. There was also some questions regarding the continued possession of the original Shockwave barrel and if after the conversion it became an NFA subjected SBS item. All this is a vague memory but I'd make sure you understand your options.

Best wishes for helping a family member.

Regards
 
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