Sig 556 lower recievers

I have one and love it. I've had zero problems with running it with LAR mags or Pmags (only ones I've tried).


Major deciding factors for me;

- Faster reloads (I'm AR Programmed)
- 10rnd Mags
- Collapsible stock vs Folder to adjust LOP on the fly.
- Because I could, there's not many around and the price was right.
 
So...If Alberta Tactical Rifle can manufacture lowers for AR's then why cant they mill up a lower that mates up to a swiss arms upper? If the upper is the registered part then it really takes the hassle out of the whole deal. Besides Its my understanding there's a fair bit of 'fitting' to get the sig 556 lower to match up with a swiss arms upper and who wants to file a $3600 gun?
 
So...If Alberta Tactical Rifle can manufacture lowers for AR's then why cant they mill up a lower that mates up to a swiss arms upper? If the upper is the registered part then it really takes the hassle out of the whole deal. Besides Its my understanding there's a fair bit of 'fitting' to get the sig 556 lower to match up with a swiss arms upper and who wants to file a $3600 gun?

They likely wouldn't be able to sell enough of them to justify the cost, there is a much larger market for AR lowers and Sig 556 lowers. If you modify your magazines no modifications are needed to the upper.
 
I have a related question - would the ATF allow a Swiss arms Upper and 556 lower enter the US? What would I call it on the form 6, Swiss Arms / 556???:bangHead:


Would the 556 line up with the PE90 or does it really need filing and modification work?

For me taking it to the US would be the only reason to get a 556 or the 556 lower.
 
I didn't get it...

In Canada Sig 556 is prohib or not?

What part is a receiver in Canada - top or bottom?

Since the serial number on the PE90 is on the upper it is the upper. On most guns the serial number is on the lower.

Therefore, can you fit 556 upper on any other receiver that is not prohibited, e.g. AR-15, AR-180B, etc?

No the upper is the registered part, thus prohib. The lower is not so you can put the 556 lower on other guns.
 
So...If Alberta Tactical Rifle can manufacture lowers for AR's then why cant they mill up a lower that mates up to a swiss arms upper? If the upper is the registered part then it really takes the hassle out of the whole deal. Besides Its my understanding there's a fair bit of 'fitting' to get the sig 556 lower to match up with a swiss arms upper and who wants to file a $3600 gun?

There was zero 'fitting' required for mine. It drops on, actually fits a little tighter than the PE90 lower on mine. No issues with mags.

Drop in replacement. I can't speak for everyone that has this lower, but on mine, I have had zero issues with it.

we looked at making these lowers here but there just isn't enough SAN rifles here to justify tooling up for a run. It's not like the AR where there are thousands of them laying around.
 
But there would BE more PE90's if people could get 556 lowers.

Would it be possible to have PE90 uppers brought into Canada without lowers? If yes, how much would they cost?

As for the lowers, you could add a premium on the first X number sold to pay for the cost of tooling-up.
 
But there would BE more PE90's if people could get 556 lowers.

Would it be possible to have PE90 uppers brought into Canada without lowers? If yes, how much would they cost?

As for the lowers, you could add a premium on the first X number sold to pay for the cost of tooling-up.

Even though having these readily available would increase the number of PE90 owners it wouldn't be enough to make producing lowers profitable.

The premium to the early adopters would make them cost prohibitive to most would-be customers.
 
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I had the chance to buy one when I was in the US but I still don't know if the ATF will let me in the US with a complete gun. It would be nice to be able to take the PE90 down there.

I must be the world's leading authority on this one.

ATF have classed the PE90 as an NFA weapon, I #### you not. They think it's a machinegun.

I sent them pictures of the upper so they could compare with their reference guns and the idiot who runs ATF Tech Branch sent me a letter back saying that the fold in the receiver where the rail is welded onto the upper was a slot for an auto sear. I wrote him back, e-mailed him, called him, I've never heard anything back.

Legally, the PE90 is prohibited from import under 18 USC 925(d)(3) as a non-sporting firearm, BUT that section does not apply for temporary imports, because they're not considered an import, which is why you can take an AR-15 in on a Form 6NIA.

I took pictures of the upper of a 556 when I was at the NRA show, but they didn't come out too clearly because it has a black finish, but as far as I can see the relevant part of the receiver is identical in design to a PE90. But yet ATF Tech Branch considers that a Title 1 firearm. Hmm...

It would be really helpful if we could get ATF to change their minds on this one because they are WRONG.

When you apply to import it, include a letter that says: "I declare under penalty of perjury that the firearm to which this application relates is not a machinegun and does not incorporate the frame or receiver of a weapon controlled under the National Firearms Act." And sign it.

Take photographs of the underside of the upper receiver from various angles so it is obvious there is no auto sear slot and include those photographs and explain there is no auto sear slot.

Eventually if they get enough applications they will be forced to look at it again.
 
Given the availability of much less expensive magazines now, is it really worth the effort?

JR

Yes, because SIG-Sauer make a stock adapter for the 556 lower so you can put AR-15 buttstocks on it and the regular PE90 stock is too long for me. Plus it means you can use the RRA 10-round mags.

Is there a stock adapter for the regular PE90 lower?
 
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