Forgive my ignorance since I have no idea about all the SBS rules, I don’t have one. Have plenty of SBR’s and suppressors. I just ordered a Shockwave and had some questions.

Specifically legalities about a Shockwave and plans for it. Can you add a pistol grip/arm brace or make it into an AOW?  Now that F1’s on eForms is getting some returns at 2 weeks, an SBS seems very attractive to me.

You can buy a Shockwave with a pistol brace already on it straight from the factory. No need for a Form1 for that or to add a brace to a shockwave. If you pony up for the $200 stamp you can do whatever you want!

Thanks. I didn’t know they came with a brace, just the birds head grip.

https://www.sb-tactical.com/product/590-sbl/

One drawback to these (at least the SB tactical one I have) is the way it attaches to the receiver requires you to remove the brace and "buffer tube" then remove the pistol grip adapter, just to be able to remove the trigger group so you can remove the bolt to field strip the weapon and clean it properly.

This might not be true of other brace designs for the Mossberg or the Remington TAC-14

Yes you can add a brace with pistol grip.  I did a lot of research before I added an SB brace to mine.  It remains a Title I gun and not under the purview of the NFA.

You inadvertently turn you shockwave into an AOW (and under the purview of NFA) if you do anything that makes the OAL less than 26 inches.

You said you are somewhat new to all of this so let me just say in closing, that the Making tax for an AOW is 200 dollar not the 5 dollars required to Transfer an AOW.  Generally if you are intentionally making a shockwave into an NFA item you would probably be better off (as far as flexibility) to register it as an SBS instead of a AOW.  The only upside to an AOW is the lack of interstate travel rules.  You don't need a 5320.20 to transport a silencer or AOW.

I don’t think I can make an AOW out of it I’d have to take it to an SOT and they could then transfer back to me for $5? I may just go the SBS route, 5320.20’s don’t bother me I have to do them annually for my SBR’s.

I have a 870 Tac-14 Arm Brace model & I can get the trigger group removed w/out disassembling any of the brace setup.  It’s tight but doable.