Okay guys, a few more question and I'll stop creating threads! (Sorry I am new to the shotgun concept and platform) I want to create my Mossberg 500 something along the lines like this:

I have done some research pertaining to CA's shotgun laws, from my understanding the format I want to make my shotgun (pictured above) would be legal to do so as long as the barrel is a minimum of 18" and has an overall length of a minimum 26" and as long as it's also a pump action and not magazine fed. Another thing, anyone want to take a guess to what is the overall length of the shotgun pictured above is? It seems like it may be under the 26" minimum requirement, if so how short should I go with my barrel to have a 26" overall length with the pistol grip?
2nd question! Where can I purchase a magazine extension tube to be able to fit 2+ additional shells, and how long does the barrel have to be to make it "flush" with the extension tube, I would like the magazine tube and barrel to be aligned, where the barrel isn't longer than the magazine tube.
3rd, would a Mossberg factory pistol grip from a 20 Gauge work/fit on a Mossberg 12 Gauge?
Lastly, thanks!
I have done some research pertaining to CA's shotgun laws, from my understanding the format I want to make my shotgun (pictured above) would be legal to do so as long as the barrel is a minimum of 18" and has an overall length of a minimum 26" and as long as it's also a pump action and not magazine fed. Another thing, anyone want to take a guess to what is the overall length of the shotgun pictured above is? It seems like it may be under the 26" minimum requirement, if so how short should I go with my barrel to have a 26" overall length with the pistol grip?
2nd question! Where can I purchase a magazine extension tube to be able to fit 2+ additional shells, and how long does the barrel have to be to make it "flush" with the extension tube, I would like the magazine tube and barrel to be aligned, where the barrel isn't longer than the magazine tube.
3rd, would a Mossberg factory pistol grip from a 20 Gauge work/fit on a Mossberg 12 Gauge?
Lastly, thanks!

-- Rifle, Pistol, Shotgun
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