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Review: SIG Sauer M400 Elite

Review: SIG Sauer M400 Elite
SIG Sauer M400 Elite

SIG Sauer is a smart, innovative company. The latter attribute has led it to come out with advanced firearms like the SIG 556 series—a semiautomatic that borrowed the best of the AR and Swiss 550 platforms. The other attribute—smart—means the firm knows when it's time to focus on what the market really wants.

Hence SIG has a full line of straight-up AR rifles and carbines, both piston and direct-impingement guns. One of the most sensible for those who don't want to spend a fortune is the new M400 Elite. It's a direct-impingement carbine with basic M4 features, including a dust cover, forward assist and single-side charging handle.

The Samson SX Series free-float handguard is light and slim and features M-Lok slots at three, six and nine o'clock. Underneath is SIG's Micro-Light gas block.

The 16-inch barrel is treated to a nitride finish and is tipped with a standard A2-style birdcage flash hider. It is free-floated inside a Samson SX series handguard with M-Lok slots at three, six and nine o'clock. It's a comfortable, slim handguard with sufficient length to accommodate any shooting style.

The gas block is SIG's own Micro-Light, mounted in the carbine-length position. The block weighs a mere 0.5 ounce, close to the weight of most titanium gas blocks costing $100 more.

The stock is a SIG-made, six-position collapsible with integral QD sling attachment pockets at the rear on both sides. The butt itself is nicely serrated to keep it in the shoulder. The pistol grip is also SIG's own—the Enhanced—and it's nicely shaped. It dispenses with the A2 finger shelf and instead sports dished-out grooves at the top that comfortably fit the firing-hand thumb and indexed trigger finger, along with a shelf on the bottom for sure hand position.

As part of the Elite package, you also get an enlarged trigger guard and an extended bolt catch lever. The bolt carrier group is DLC (diamond-like coating) finished, providing low friction and high resistance to corrosion. The gas key is properly staked.

The M400 Elite sets itself apart with the Romeo 5 red dot option. Other notable features include the Enhanced trigger and enlarged trigger guard, extended bolt catch and SIG furniture.

Where the Elite really departs from the pack is the SIG Romeo 5 red dot you can order as part of a package—for only about $160 more than the rifle sells for bare. The sight alone has a suggested retail of $220. It's a trim, non-magnifying sight with 10 brightness settings and a two-m.o.a. dot that's adjustable for windage and elevation.

The Romeo 5 comes with two rail-mount base options: a high one for co-witnessing with irons and a low one. As someone who likes to have my cheek as snugly on the stock as I can, I expected to prefer the low mount, but for me the base was a wee bit too low to view the entire sight window comfortably.

The Romeo 5 also features MOTAC, a motion-sensing feature that shuts off the sight after two minutes and then automatically turns the sight back on when the sight moves. I tested it, and it works as promised and should provide peace of mind for those who worry they'll forget to turn off the sight before sticking the rifle in a case or gun safe. The Romeo 5 is waterproof to one meter and fogproof.

For accuracy testing I removed the red dot and installed SIG's new Whiskey5 2-10X riflescope in a Weaver one-piece SPR mount. All in all, I was impressed by the Elite's accuracy, although the Enhanced trigger doesn't do it any great favors from the bench. According to product manager Patrick Hanley, it is polished in a tumbler and then given a DLC coating for smoothness. The result is certainly smoother than your standard gritty GI job and has almost no creep—but at nearly seven pounds, the sucker is heavy.

While the trigger is way heavier than I prefer for shooting groups, it works great for practical shooting. With the red dot back aboard, I did some rapid firing, and the gun behaved quite well—coming back on target quickly and delivering hits out to 200 yards with ease from supported and unsupported positions.

The gun ran flawlessly with the supplied metal 10-rounder that ships to restrictive states, as well as a number of other mags. Buyers in most places will get a 30-round polymer mag.

As expected, the rifle ran 100 percent reliably with all the ammo I tested. I live in a restrictive state, so the company provided a 10-round aluminum mag, which was marked D&H Tactical. I shot it along with some blocked PMags I had from my California days, and all went well. For those who don't live in a state with such a burden to bear, the Elite ships with a polymer 30-rounder.


If you're in the market for an M4-type AR-15, you already know there are tons of choices out there at all price levels. SIG's M400 Elite seems to me to be Goldilocks' "just right" choice: a decently accurate, well-built carbine with features that should ensure reliable service for years to come. And with the Romeo 5 sight as the icing on the cake, it comes in at a reasonable price.



TYPE: direct-impingement AR-15


CAPACITY: 10-round metal (tested) or 30-round polymer mag

BARREL: 16 in. nitrided w/A2 flash hider

OVERALL LENGTH: 33-36.25 in.

WEIGHT: 6 lb., 6 oz. w/empty 10-round mag

FURNITURE: Samson M-Lok handguard, SIG Elite grip and 6-position stock

TRIGGER: SIG Enhanced, DLC coated single-stage, 6.7 lb. pull

SIGHTS: SIG Romeo 5 (as tested); continuous top rail

PRICE: $1,359 (as tested)


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