To me one of the greatest disappointments with the Sig 556 has been the sights. The early rifles had none, and even the final generation factory supplied sights were IMO too tall and looked like something out of a Tapco catalog. I always thought that the lack of good factory sights held back the adoption of the platform (especially early on). I have been reading about MFI sights for some time now, but never jumped on them due to concerns with removing the factory Sig rail, and issues I have heard on forums about replacing the front Sig sight. Also, being a cheap bastard, I didn't want to layout the cash, given my factory sights were "good enough".... barely.

After living with my factory sights for 5+ years, I decided I had enough. Lucky for me, the price on the MFI sights has come way down. I picked up front and rear sights for both my 556 rifles for $350 delivered. Turns out the install was a breeze too. I heated my rail screws for about 30 seconds with a soldering iron. Then using a Torx 20 bit, they came out easily. The front site install is a not hard either. Just make sure you have a 1/16 inch punch.

The MFI rail and front sight is a precision piece, and fit with zero hassles. All in all, I was able to swap out the sights in less than 15 minutes (per rifle). I plan to take my rifles out this weekend to zero them. I can say this, MFI makes a nice  product, and the install could not be more simple. If you are living with the factory sights, or have some "AR15" height sights, you might want to look into MFI, given today's price point. If your interested -> Shows 3 in stock...

A few pictures...

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If Sig had released the initial rifle with decent sights, furniture, and quality control, I suspect things could have turned out differently.

I was very impressed with mine... needed them to complete the rifle

Anyone know if this set fits on the 556R?

Kind of funny, when I bought my 556R the dealer gave me a set of SIG sights for it.  He said most people he ordered the rifles for didn't want the factory sights since they were putting scopes or red dots on their rifles and had no need of iron sights.

I installed them, sighted the rifle in, but planned on eventually replacing them.  But the longer I used them, they sort of grew on me and they're still there.

I put the Troy full length rail system on my 551-A1 and went with HK416 sights. Similar to yours, but they are all on the same continuous top picatinny rail.

Thanks for the heads-up, I FOed on a set.

They will fit any 3 screw rail 556. I imagine they can be sighted for 7.62x39, but I have not tried it personally because both of my rifles are 5.56.

They sure do. I put a set on my 556r a few weeks ago.

Ordered the sight set, do those 552 hand guards fit my 556P Swat?

Says 556P pistol but not the swat pistol specifically, would like to ditch the quad rail on my SBR

Should fit no problem. I ditched the rail on my rifle length swat, just to damn heavy.

the mfi 552 style handguards  will fit on your 556p , it doesn't look like they come with the handguard cap though which you'll need.

real swiss 552 handguards would be too short to fit a 556.

i prefer the quad rail on my sbr as it locks up tighter than the plastic handguards did , especially with accessories mounted to it.

that's a great looking little sbr , the mfi sights should be much nicer than the sig factory sights you have on there.  the factory 556 sights were all terrible and were the first thing i replaced on mine.

slag --- the mfi sights look right at home on your 556 , the gun looks tits

Yeah, i'm torn, I like a vert grip on my SBRs and the light but like the classic look of the hand guards.

And I agree, the rear sig diopter blows.

with the classic folder and iron sights i guess i would have to agree the plastic handguards fit the part

if you could find an original set and drill the holes yourself i would try to go that route.  if i remember correctly the mfi handguards were thinner than the original sig ones.  at the prices they're blowing sig parts out at though they would be hard to pass up.

Not working with my SWAT quad rail

Now I have to decide if I grind the rail or the quad rail.

OP, can I trouble you for a pic at the same angle as mine so I can compare?

I ditched my rail for a standard handguard when I updated the sights. The weight was a bit much. Personally I would grind the Sig rail before the MFI rail.

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Thanks for the pic, I ended getting the hand guard set and it showed up today (USPS).

To be honest they feel cheep and move in the hand as I grip them. Doesn't help that they are too short (about a strong 1/8"), if the manufacturer couldn't get them perfect then i'd have liked to see them long with a note saying some sanding may be needed.

Easier to take a sanding block to the ring end then adding material. I'll probably try adding epoxy inside the ring and sand it down

Sights look like a winner, hopefully I can get to the range next week I sight her back in.

MFI 552/553 type handguards for the 556P are well known to be fragile, have fitment issues. Frankly the factory 552/553 Plastic handguard seems like an afterthought. They are pretty loose when you start adding pic rail, vfg, etc. The railed fore end is a must on the 552/553 (and 556P/sbr) IMO. I recommend re-install of the railed fore end and mod the MFI rail to fit.