The Ultimate Firearms Destination for the Gun Lifestyle

Sig Sauer’s new M400 Tread is more than just an entry level rifle

It’s hard for most of us to look at the AR platform with the eyes of a new shooter, but I recall the time I laid eyes on a Colt catalog as I shopped for my first AR rifle.

I remember looking at a dense page of type that listed about 50 rifles, one per line, using an impenetrable shorthand for every spec and feature. The differences between models were stated as nothing more than a letter or number in a string of text; CL 14.5, 1/2-28, FSB, FH, CLG, H2.

In context, all those cryptic abbreviations make perfect sense now. But, years ago I had no idea what any of that meant. Further, if I wanted to pick up a new handguard or other accessory, I was still feeling around in the dark since I didn’t know what terms like, “delta ring compatible,” meant or what muzzle thread pattern I needed to order when adding a brake.

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The M400 Tread basic rifle with all the Tread branded accessories. Photo: Firelance Media

It’s with these wide eyes I look at the Sig Sauer Tread program and smile. There are a ton of ARs on the market, and on its face the M400 Tread is exactly that… just another budget-priced, factory AR built by a reputable manufacturer competing for space on very crowded gun store racks.

The Tread differs from its competitors in one, very important way that has nothing to do with the rifle itself. Along with the M400 Tread, Sig’s releasing a suite of OEM upgrade parts that remove all the mystery of compatibility from the AR upgrade process.

Choosing compatible parts for the Tread is as simple as finding the Gadsen yellow logo on the box of a Sig accessory. It makes the Lego concept that veteran AR owners take for granted and makes it accessible to the newb. To quote Sig’s EVP of Commercial Sales and Chief Marketing Officer Tom Taylor, “It’s like Garanimals for guns.”

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Sig’s Tom Taylor introduces the M400 Tread to the media at the Sig Academy. Photo: Firelance Media

Of course, all of this is pointless if the base M400 Tread itself is a dog. And it’s no dog. I spent a full day at Sig Sauer’s Sig Academy in New Hampshire shooting the rifle in two configurations. In the morning, I was introduced to the M400 Tread in it’s budget-priced, out-of-the-box configuration. During lunch, Sig armorers took the gun and swapped the basic parts with Tread branded upgrades.

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In its basic $799 configuration (above and below), the Tread includes a mid-length gas system (a first for Sig), 1:8-inch twist stainless steel barrel, low profile gas block, an aluminum handguard that’s partially covered in M-LOK slots, a single-stage, mil-spec trigger, ambi controls, QD sockets on the lower receiver, and a Magpul MOE SL-K stock.

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The stock M400 Tread on the range. Photo: Firelance Media

On the range, I topped the rifle off with a Tread branded Sig Romeo 5 red dot sight, zeroed it, and spent the morning working basic presentation drills at close distances. I didn’t have the opportunity to shoot accuracy groups, but zeroing the gun with Sig’s 55gr Elite (ball) ammo from the prone at 50 yards produced groups tight enough to assume the gun could print under an MOA.

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Zeroing the Romeo 5 optic. Photo: Firelance Media

The stock trigger is entirely DLC coated and the pull is 7.5-8.5 pounds. I could feel the resistance when shooting groups, but the break was clean and consistent. Running carbine drills, the trigger felt appropriate and any trigger snobbery quickly faded into the background. I put about 200 rounds through the Tread in this configuration and had no stoppages.

The gun handles well and the thin, rail-less handguard felt a lot better than it looked. The only complaint I have with the Tread in this bone-stock setup is how hot the handguard became after a few mags. Without holes to vent heat, the handguard is a heatsink for the barrel and barrel nut.

Overall, the off-the-shelf gun ran flawlessly, performed better, and felt tighter than a lot of $1000 ARs I’ve tested.

Breaking for lunch, the Sig armorers stripped the budget parts from the gun and replaced them with a host of upgrades that turned the $799 Taurus into an $1165 Mustang, not including the $149 Sig Romeo 5, 2 MOA RDS.

The reliable personality of the rifle didn’t change a whole lot with the upgrades, but it certainly woke up. The gun was Less Than Zero Robert Downey Junior in the morning session and became Iron Man Robert Downey Junior in the afternoon.

Two things, in particular, contributed to the rifle’s awakening. The upgraded 4.5 pound, flat-faced, single-stage trigger and the 3 Chamber compensator. The $119 trigger feels better than a $119 trigger should, and the $49 comp flattened the gun out as well as a custom-tuned comp. I was as shocked to feel that as I was to write it, by the way.

The upgraded handguard ($149) shares the similar, slim profile with the stock handguard, but it vents heat much better than the slab-sided stock handguard. And, the final upgrade we opted for was the ambi charging handle ($49). Sig also has flip up iron sights ($149) and a few M-LOK handguard accessories that we didn’t mess with.

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The upgraded M400 Tread. Photo: Firelance Media

The afternoon session was barricade shooting, positional drills, and a capstone run along Sig’s jungle trail shooting course that has more than a half-dozen shooting positions spanning a hundred yard tromp through the woods. Moving through the woods, you get a little closer to a set of steel targets you engage from each position. The targets start out at about 250 yards and are at about 100 yards by the last position. Scoring hits easily from all positions proofed the gun’s practical accuracy, even if we didn’t have the ability to shoot groups.

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The upgraded M400 Tread on the Sig Academy “Jungle Walk”. Photo: Firelance Media

After 500 more rounds in the afternoon, I still hadn’t logged any stoppages and I grew to really like the Tread. It didn’t feel at all like a price-point product in the morning, and it certainly didn’t feel like it in the afternoon.

The fact that the handguard, trigger, muzzle device and all the rest of the Tread branded upgrades are end-user installable using non-specialty tools means anyone can buy the stock gun and transform it into a performer. They can do it one part at a time, without waiting on an armorer, without head-scratching… and on a budget, as the Tread parts are reasonably priced.

Sig is releasing the entire M400 Tread line Monday, 10/1/2018 and we expect the rifles and all the accessories will be available for purchase from your local gun shop within a few weeks.

(Thanks to Sig Sauer and Matt Stagliano of Firelance media for supplying images.)

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