The AK-47 is one of the most popular firearms ever made. Millions of copies of the firearm have been used in nearly every single conflict worldwide since the gun was first produced, and it even appears on the national flag of at least one country. Its reliability is unquestioned, its effectiveness well acknowledged, and its ease of use is without equal. But SIG SAUER thought they could do better — produce a modern AK-47 for the modern world. The result: the SIG SAUER 556xi Russian.
The SIG SAUER 556 Classic rifle is the modern civilian equivalent of the SG550, the modern infantry rifle for Switzerland. It has all the same major components and operates identically to the military rifle produced by the SIG half of SIG SAUER, but has been customized to meet the needs of the American market. Introduced in 2014, the 556xi line of rifles is an updated version of the 556 Classic to include some more modern features.
Specifically, the 556xi Russian was apparently designed with export in mind. SIG SAUER makes no attempt to hide the fact that what they care about most is military contracts, and with a large number of countries sporting a stockpile of aging AK-47 rifles providing a modernized version that takes the same ammunition and magazines is a no-brainer. The question, however, is whether this 556xi Russian is really an upgrade.
The most obvious change to the gun from the 556 Classic design is the addition of a set of metal handguards with a proprietary modular rail attachment system. This is the same system found on many of SIG SAUER’s other firearms, and while it does work I think most people would appreciate it if they had gone with a more commonly available system like keymod.
There are other options available for the handguards from the factory, including a slimmer Magpul M-LOK system, but again I really prefer either keymod or a standard Picatinny rail.
While the side sections need some additional parts to become functional, one of the definite improvements is the addition of a full length top Picatinny rail. The 556 Classic used plastic handguards and so only had about as much rail space as an A4 upper receiver, but the full length metal handguards o the 556xi Russian allow for a little more real estate to be made available. Along with that rail, the fixed (yet flippy) iron sights of the 556 Classic have been replaced with Picatinny mounted flip-up iron sights.
Since we’re up here at the top of the gun, let’s talk about another feature from the Swiss rifle. The gun has a fixed charging handle like the AK, but instead of just saying “screw it” and leaving the rear area of the receiver open to the elements SIG SAUER has a rubber dust cover enclosing the rear section. The charging handle travels through the dust cover just fine, and it closes once again as soon as it is back in battery. A nifty design feature indeed.
Another upgrade is the stock. Instead of the “one size fits all” approach of the 556 Classic’s stock, the 556xi sports a stock with an adjustable cheek rest. Which is great for accurate shooting, and something that more companies should be providing in my opinion. The stock easily folds to one side, and unlike the American AR-15 design the gun can be easily and reliably fired with the stock folded.
At the rear of the gun, there’s a mounting location for a sling swivel or eyelet. The gun comes with the eyelet on the left side of the receiver, but that can be pretty easily swapped.
With the typical American setup, the recoil assembly is located behind the bolt carrier. With the Swiss 556 rifle, the recoil spring is wound around the operating rod. The gun is a gas piston design, meaning that gases are vented from the barrel into a chamber, and the force of those expanding gasses act on a piston which moves rearwards and moves the bolt and bolt carrier back to cycle the action. In this gun, that same piston will then pull the bolt and bolt carrier forward and back into battery, completing the cycle. Its a nifty design for sure, but I have some concerns about putting a spring into the same compartment where you are directly venting gasses. Seems like a good way to get it dirty real fast, and cleaning a spring isn’t exactly as quick as cleaning the piston on an AK-47.
The operating rod and bolt carrier are connected using the charging handle, and one of the nice side benefits of that configuration is that the gun allows the end user to swap the side of the gun that the charging handle is on with ease. Whether you’re a leftie or just have too many knobs on one side of the gun to get a proper grip, swapping the charging handle is as easy as pushing down on the release and pulling it out. Re-inserting is just as simple. In fact, disassembling the gun is about as easy as it gets.
Disassembly of the gun is a snap. Pull the two takedown pins (just like an AR-15) and the upper and lower receiver come apart. Then pull out the charging handle and the bolt will slide free. Rotate the gas plug in front and the gas system will slide out as well. Easy as pie, no hammers required.
Rounding off the general overview, the gun takes standard AK magazines. Both steel and polymer work, which is nice, but the gun ships with a TAPCO AK magazine. Which is a little strange, since the rest of the gun seems to be made from quality parts and well machined yet they went with a chintzy plastic magazine. Eh, it worked, so I can’t complain much.
So much for the general overview, let’s get to the feel and function.
The controls on this gun feel like they were made for someone with bigger hands than I have, which I don’t think is possible. The safety selector lever is ambidextrous, but incredibly tough to operate. I need to move my hand out of position to use it, and moving it from one position to another takes some effort. In short, it sucks.
What to know another thing that sucks? The trigger.
This is quite possibly the worst trigger that I have ever tested. Ever.
The trigger is a two stage affair, and the first stage takes about half an inch of takeup over a good eight pounds of force. The second stage is all the way at the end, and overtravel is controlled by adjusting the screw at the rear of the trigger guard. The trigger is smooth and creep-free, but as heavy as yo mama. Adjusting that trigger pull weight isn’t possible with the rifle itself, and while after-market trigger mods are available the overall reviews seem to indicate that installation and tuning can be “tricky.” Not something I’d want to mess with unless absolutely necessary, in other words.
Out on the range, the gun runs just fine — so long as you had your Wheaties that morning. Working the trigger is a workout all on its own, and not something I really enjoyed doing. A magazine or two is more than enough, then I needed to swap to some rimfire for a bit to give my poor digit a break. The gun ran just fine and ate whatever I threw at it, including the Hornady ammo that the Mk47 Mutant didn’t appreciate. And the recoil, as a cute French video journalist who was following me for a couple days can attest, is downright enjoyable. But that trigger is an absolute beast, and not in a good way.
That trigger had a huge impact on accuracy.
Out on the 100 yard line, I used a U.S. Optics MR-10 scope in some Warne scope rings and Hornady ammunition to test out the accuracy of the rifle. On this same day in this same exact configuration, I was shooting one-hole groups with a different test rifle and that same scope. But with this gun? The results were decidedly disappointing.
This is the very best group I fired all week. A more representative 10 round group registered closer to 4 MoA., but I cherry-picked this 5-round group. For this exemplar, I put the extreme spread on that group at a hair north of 2 MoA. Considering that the Mk47 was grouping right around 1.5 MoA with the exact same box of ammunition and the exact same configuration, this rifle is objectively worse. And not just by a little bit. For those wondering, the order of the rounds was bottom left, top right, bottom right, top left, middle right. The group didn’t start small and open up, it was terrible from the beginning.
SIG SAUER Confirms
Given the problems, I asked SIG about the problems I was seeing and sent them the rifle. I worked with their product manager John who confirmed that every criticism of the gun I’d found was 100% accurate. The trigger tested in their shop at between 8.5 and 9 pounds, which is outside their stated specs. And the accuracy of the rifle, even when fired from a rest, was unacceptable. In short, as I’d found, the gun was awful.
Apparently the rifle I received from the factory was from an early batch. They claim that the issue has been fixed in later versions, and accuracy has improved. I’d like to take their word for it, but we need to report what we found. Even if they do fix the issues with the gun I tested and send it back, it’s no longer a factory gun. I can only review guns based on how they perform, and reviewing something that has had a chance to be custom-tuned by their gunsmiths isn’t representative of what the average person would see in an off-the-shelf model in their local shop.
So this review based on my assessment of the original rifle. I will also make you, our readers, aware of the possibility presented by the manufacturer that the gun provided doesn’t accurately represent what’s on store shelves. And finally, when this rifle (or a factory-fresh version) comes back from SIG, we will re-test the gun and run a follow-up article detailing how it performs and linking to this review.
We now return you to our regularly scheduled complaining.
The gun works. It shoots pieces of lead at high velocity in the general direction of a target, and does it reliably. But the accuracy isn’t good enough to be useful in any scenario I could think of, and the ergonomics leave me wanting. It’s a cool gun, and with some changes I think it could be a real contender, but as-is I think SIG SAUER missed the mark.
Specifications: SIG SAUER 556xi Russian
Barrel: 16″ 1 in 9.5 inch rifling
Weight: 7 lbs
Length: 35.8 Inches
Magazine: Standard AK-47
Street Price: $1,599.00 ($1,299.95 street)
Ratings (out of five stars):
Nope. My AK shoots better than that. And it only cost me $500.
Ergonomics: * *
In general, the gun is pretty good. The recoil is pleasant, the handguards are grippy yet not aggressive, and the charging handle feels good. But the trigger is abysmal, and the safety is as easy to use as the Large Hadron Collider.
Ease of Use: * * *
See: terrible safety.
Reliability: * * * * *
No issues whatsoever during our range time with the gun, even out in the Texas dirt and dust. Ran just fine.
Customization: * * *
There’s a full length Picatinny rail along the top and aftermarket parts available for the trigger, but there isn’t the depth and breadth of associated gubbins available like for the AK or the AR platform. Oh, and the rail system is proprietary.
Overall Rating: * 1/2
The Mk47 Mutant is about $100 more expensive, but worth the cash. This rifle looks cool and the operating parts are nifty, but the execution is flawed. A better trigger and perhaps a better barrel would make this gun a shooter, and then we’d have something to talk about. But as is? Pass.