SIG 556 question

[firefirghter2]

Hello All,

I am interested in buying this barrel and want to know if it will be able to fit on an AR15 platform? here is a link to the site:
http://www.sigsauer.com/CatalogProductD ... -swat.aspx

please let me know if it is compatiable.

Thank You.

[Sigfan220]

Do you mean upper? Not that it matters but the gun you listed isn't even close to an AR-15 so I'm going to say no. Others might know more but being completly differant designs I find it unlikely they are compatable.

If you mean the barrel - why not buy an AR barrle for said AR? Everyone and their brother makes AR barrels in about every possible length, contour and finish.

Just my $0.02 buy the right stuff and not try and make an overpriced Sig part work in place of them. Maybe I'm lazy though...

[firefirghter2]

Thank you for the input. Yes I did mean upper. I was going to be able to get a good deal on it but wanted to make sure first

[kollector03]

Completely different rifle and not compatible with an AR lower at all.

As an aside, I have a 556 Classic in 5.56 as well as a 556R in 7.62x39mm and they are two of my absolute favorite rifles. If the 556 platform is interesting to you, I would highly recommend purchasing a complete rifle rather than trying to piece one together.


Don

[Pinnacle]

The 556 has been around for a long time and it is one of the worlds best rifles... Not at all even close to an AR. Totally different and not too much more than an AR of comperable capability in cost.

[maddhunter]

How would I, as a noob, be able to look at the website picture and know that the upper would not work?

Just curious

[solidgun]

How would I, as a noob, be able to look at the website picture and know that the upper would not work?

Just curious

By looking at the pictures alone will not give you any idea on what fits. However, the 556 is a different platform, so you have to have the understanding on what platform you are working with. If anything, you can just post links and ask people to see what "should" fit.

[jshuberg]

Because it's not an AR-15.

I don't know if they have solved the problem or not, but for awhile a couple years back they had a problem with the bolt carrier impacting the trunnion in the upper receiver. There was slight scarring of the carrier at the point of impact for those rifles, and the result was a loss of accuracy. Sigs initial response was to tell people there was no problem, but eventually they had people send in the defective rifles and ground down the corner of the carrier that was being impacted, despite the problem being with the trunnion.

If you're looking at buying a 556, cycle it a dozen or so times and pull the carrier and look at the front to see if there is any indication of contact where there shouldn't be. If there is, pass on it. More info:
http://www.sigarms556.com/viewtopic.php ... 9cc86211b1
http://www.sigarms556.com/viewtopic.php?p=37952#p37952

Aside from that problem, the Sig 556 is an excellent rifle! It's a sort of cross between a Swiss Arms 551 and an AR-15.