SBR AR57 Upper w/ SS Sparrow?

[MACTHEGUN]

Only if the rail or handguard is permanently attached.

Modular, meaning a 1 piece unit (cannot be disassembled from the upper receiever).

 

[Pinecone]

That should be cool.

BTW, modular means means many interchangeable pieces.

Modular design, or "modularity in design", is an approach that subdivides a system into smaller parts (modules or skids) that can be independently created and then used in different systems to drive multiple functionalities. A modular system can be characterized by the following:

(1) Functional partitioning into discrete scalable, reusable modules consisting of isolated, self-contained functional elements.
(2) Rigorous use of well-defined modular interfaces, including object-oriented descriptions of module functionality
(3) Ease of change to achieve technology transparency and, to the extent possible, make use of industry standards for key interfaces.

 

[smdub]

Reread the ATF description. Only needs to be permanent if attached to the BARREL. Any regular free-floating rail that takes a tool to get off would be fine. The barrel unscrews w/ a tool (its not pinned to the upper.) The buttstock comes off (usually without a tool.) etc. The posted regulation applies to barrels only.

If you can meet 29" w/o a barrel then the barrel length doesn't matter for a SBR.

 

[Pinecone]

If you say so. I would definitely ask the BATFE for that in writing before I made one.

 

[MACTHEGUN]

BTW, modular means means many interchangeable pieces.

Lol, you're absolutely right!


My brain said "Monolithic" and by the time it got to this thread is said "modular" (damn auto-correct).


Well, at least I got the "Mo" right!


I just noticed I called my Magpul stock a "CTS" as well, lol.

 

[Pinecone]

I was wondering.

 

[rsideout]

I'm so glad that my 2 AR57 SBR's were approved prior to all this SB281 bulls%#t.

 

[doofoo]

I'm so glad that my 2 AR57 SBR's were approved prior to all this SB281 bulls%#t.

Got any pics? Trying to get some idea's..

 

[MACTHEGUN]

Got any pics? Trying to get some idea's..

I took some pics of mine, as soon as I figure out how to post them I will (I currently have the 16" barrel upper). With the Magpul CTR and Enhanced buttplate (.70") I got a total length of 29 1/4" - 29 1/2" to the end of the rail with the stock extended.

From bolt face to end of rail, I got right at 11" so with a 6" barrel (+/-) you could bring the suppressor just to the end of the rail and be in compliance w/SB-281.

IMO your Sparrow SS would be perfect for this application and will probably be my next suppressor.