So with 922(r) I've got to replace about $200 in parts to make it legal for a magazine extension...what if I SBS? Do you still have to get 922(r) compliant then?

It comes into play with SBRs so I'd say yes

922 is not really an issue with the Benelli M4 SBS 14" as it only has a 5-shell magazine.  This is why you can buy the 14" SBSs with a C-stock (11724 model) with no addl hurdles beyond it of course being a NFA SBS item.  The much more common 18.5" model, when user upgraded to a seven-shell mag, has the 922 considerations.

922(r) status has nothing to do with capacity.

I believe all 11724 models are imported for LE use, which is why their first sale (or shipment) must be to a LEO or agency. Once that occurs, they may be re-sold to anyone, and are permanently exempt from 922(r), pursuant to 18 USC §925.
As a post-1968 NFA item, they're only importable for LE or government use. Any firearm (including Title I 18" Benellis) could fall under the 925 exemption. You might find a used gun a cop's selling that they don't even realize is exempt. This is one reason 922r violations are rarely prosecuted. No records proving the exemption status are kept (nor required), so it's generally impossible to prove "beyond a reasonable doubt" that most random used guns weren't possessed by or shipped to LE for official use at some point.

With Benelli M4 Entry guns, the dealers are getting them in knowing the demand to re-sell to private citizens, hence the high prices. Sometimes LEOs also cash in on their lucrative exempt status, although purchasing with the intent of resale is prohibited. 

OP, to answer your question... If your gun has never fallen under the 925 exemption then yes, it is still subject to 922(r) regardless if you register it as an SBS or not.

are you planning to chop the barrel?

the only non compliance on the gun as originally designed was the greater than 5 round tube.  Not sure how staying at 5 rounds or less would create a 922r issue.

I'm playing with the idea of chopping it.  To get 922 compliant and make it hold 8 rounds will cost more than a stamp and a new barrel

Since i'll probably never get my carrier comp tube I ordered on the 23rd day of October in the year Two Thousand and Sixteen, i'm not worried about 922

KitBuilder is correct.

It is my understanding that they come into the country as full length 18" barrel guns, but the gas port and front sight are configured for 14"... then Benelli USA cuts the barrel down to 14" (hence why the entry guns are not threaded for chokes) and offers them only to LEO agencies. I got my factory Entry M4 as a former LEO gun, and it is 100% Italian parts. My dealer gave me copies of the original agency order with the gun's serial number on it along with a disposition form showing it sold out of agency possession (although I doubt I will ever need them, I think my approved Form 4 is good enough).

That's the reason Benelli cannot just sell the SBS M4's to anyone though, because they don't comply with 922(r). Apparently Benelli only wants to go through the trouble of meeting 922(r) compliance for some of the 18" models, which would be why they're offered to the general public.

The good news is that you can buy an ex-LE gun and never have to worry about 922(r) with it, but of course this generally comes at a premium cost.

Super technically, 19.75" guns, sights all set back as you say. They look really weird before they get chopped! This is per Benelli's tech line, I found someone VERY switched on there that didn't normally answer the tech phone who answered a ton of ?'s for me. My one question is, since I have not gotten hands-on with one yet...how does the chop-job look, up close? Anyone have MACRO setting pics of the muzzle on an OEM M4 SBS?

No pictures, but I have personally seen dozens of these barrels for choke tube threading. Other the chrome lining not covering the end/crown of the barrel (visible inside the bore only) you cannot tell the barrel has been cut. The job was done correctly, no pipe cutters used at Benelli

I completely suck at taking pictures and only have my phone to do the job, but here is a close shot of the muzzle of my factory SBS.



It is a very, very clean job as already stated by GunCat (who I believe is from Rose Action Sports, which means he knows what he is talking about). There is no bevel on the inside or outside of the cut, and while it isn't evident in my shitty photo the end shows concentric swirl marks that make me think it was spin-cut on something like a lathe and not just a saw cut and touch up.  The refinish on the cut end matches the finish of the barrel itself perfectly.

I just bought one, and it looks identical to yours, and the front is re-finished. Not "left white" like some of the earlier guns. Also, I do have a slight bevel on the inside. I guess that might be an exaggeration, it's VERY SLIGHT. Looks like they barely broke the edge of the corner pretty much. I had to swap out the trigger guard on mine since I wanted a metal one. It was polymer.

Just curious, but on the factory 18.5" barrels already threaded for chokes, the chrome lining doesn't cover the threads, does it? It's done, and then the barrel threaded, and it stops where the skirt of the choke abutts the inside of the bore, right?

the chop job on mine is sloppy...   I will get it threaded for chokes one day and have them clean it up.

with the open choke, its not kidding on the entry aspect.  at 25 yards, a skinny guy standing sideways could get luck and have all the pellets fly past both sides of him...

I went with the factory SBS to avoid the 922 issues of making it hold a full capacity tube

What about Flite Control? It should LOVE that stuff.
Also, you went with a weapon limited to 5 rounds, so you could add more than 5 rounds and not have to buy a few different parts to do it? I am confused.