Rifle Review: SIG SAUER M400 TREAD — Way Beyond Basic

I recently attended a seminar hosted at the SIG SAUER Academy. The purpose of the excursion was an in-depth analysis of the recently introduced M400 TREAD. The M400 TREAD is a SIG SAUER first in terms of creating an “entry” level AR product. SIG has always resisted entry-level product category, feeling it is only a race to the bottom in terms of pricing and quality. I will admit to some initial skepticism involving the TREAD. This stems more from an already saturated AR market than anything to do with SIG SAUER. What makes the SIG TREAD a worthy AR candidate? I’m going to tell you.

SIG Academy Instructor putting M400 Tread through its paces.

Typical of SIG SAUER, though the TREAD is an AR in a basic configuration, it can be viewed as offering more than a typical stripped-down AR. This is thanks to its ease of upgrading with SIG accessories specifically made to mate up on the TREAD rifle. “ROOM TO GROW” is the SIG catchphrase with the M400 TREAD.

The SIG TREAD naming pays homage to the Gadsden flag of the American Revolution. Most are familiar with the yellow background flag with a coiled rattlesnake with “DON’T TREAD ON ME” written under the snake. The homage paid by naming their new direct impingement AR TREAD is based on the AR’s ever-growing popularity in the US market as well as SIG’s belief every freedom loving American should own an AR. Just as we depended on gun ownership at the birth of our nation’s independence the same analogy can be made today as certain segments of society are back at it urging more and more government control in our lives — never a positive. The same SIG principles that guided their other rifle products such as SIG516 and MCX Virtus are present in the M400 TREAD. Only after a thorough survey of the topic did SIG move forward.

All Business

The SIG TREAD is a no-nonsense AR rifle. The collapsible buttstock is easily adjusted for length of pull and/or transport. The TREAD is one of lighter AR versions on the market; especially considering that it features a full-length rail and stainless steel 1:8 twist 16″ barrel, weighing a svelte 7 pounds. The low profile micro gas block found in TREAD is machined from stainless steel and is much lighter than standard low profile gas blocks helping to shave weight from the rifle and keep it balanced properly. A mid-length gas system is used for a smoother recoil impulse. Ambidextrous controls are another nice touch with the base M400 TREAD rifle.

SIG SAUER’s thought process with the M400 Tread was to create a lightweight, reliable, simple to operate AR. The SIG M400’s minimalist rail allows for hand placement most conducive for shooter comfort and efficiency.

A minimalist SIG M-Lok rail design further assists in weight savings. The SIG rail system permits the barrel to be free floated for better accuracy. The M400 TREAD shows versatility in satisfying customer needs by not using full-length quad rails, but instead a lower profile handguard with adjustable M-Lok sections. The M-Lok handguard minimizes weight and prevents the TREAD from being front heavy impacting handling, yet allows for effective cooling of the barrel and secure mounting of sling swivels and flashlight attachment interface. The minimalist approach for rails still allows plenty of room for VFG, bipod and lights/lasers if so needed. Not all weapons need rails and an array of accessories to be considered viable. It’s often best to let the end user how to set up their rifle.

M400 Kit

Two major aspects of TREAD design separate it from competitors. The first is the free float handguard design. A free float tube allows for better accuracy. SIG provides this while still allowing for accessories to be added. Armorer training is not required to be comfortable with replacing handguard and installing accessories. In fact, loosen two screws and several length handguard options are available for use on the TREAD. This leads us to the second part of the package — a line of fully proofed TREAD accessories to take the base rifle to a more advanced realm with ambidextrous charging handle, multiple Vertical Foregrips, metal BUIS sights, 3-chamber muzzle compensator, 4.5 lbs. single stage flat blade trigger upgrade, SIG Romeo5 red dot etc. All of these accessories come in distinctly labeled SIG TREAD containers featuring the yellow TREAD symbol so no mistake can be made if viable for use with the SIG M400 TREAD AR rifle.

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The M400 Tread is a great value. The kit is packed with accessories and it’s ready for immediate use once unboxed and enhanced easily.

Let’s face it — iron sights as a primary means of aiming ARs have been replaced with red dot optics. SIG SAUER accepts this realism and makes available their Romeo5 as part of the TREAD accessories. This is a sound choice for a red dot straight. End users can still mount back up iron sights with SIG also having these as part of the TREAD line up. The goal with the M400 TREAD is to have dealers not only feature the rifle, but also the SIG accessories. This offers peace of mind to consumer and retailer that the package has the full support/backing of factory testing with the customer not being the guinea pig of finding out what accessories work with their purchased AR rifle.

A sampling of some of the SIG Tread accessories intended for use with the Tread rifle. SIG has spent time developing and proofing these parts so users have no worries about fitting or working with the Tread rifle.

Beyond Basic

To see what the M400 could do multiple scenarios involving shooting/moving engaging multiple targets behind barricades while switching magazines, working in/around a vehicle, and then running steel plates at every imaginable range, 10 yards out to 225 yards, left no doubt the M400 TREAD was way beyond basic. The SIG SAUER experience started with a specific TREAD and assorted accessories assigned to each participant. After a brief sight confirmation period, the SIG SAUER Academy instructors began walking the group back to different firing lines. Another training evolution had the group meet in a classroom while accessory upgrades were installed before heading back out to the range — this literally took only minutes to do.

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A “Hogan’s Alley” scenario involving multiple magazines changes moving between various firing points against a multitude of designated targets was run with the rifle we set up. Switching between shoulders was required based on firing positions. The TREAD’s ergonomics and ambidextrous controls were really appreciated. The culminating training evolution consisted of a “Jungle Run” course involving multiple firing positions.

Todd engaging targets during the Jungle Walk.

The M400 TREAD proved itself at the SIG Academy with numerous rifles and thousands of rounds fired. The TREAD is a top choice for any AR connoisseur no matter if first rifle or tenth. The performance combined with price is the quickest way to appeal to the shooting public — the SIG M400 TREAD will have no problem proving its worth.

The AR platform seems to be coming full circle in terms of returning to a sleeker more lean form. The SIG M400 TREAD is an excellent example of this. The benefit of the TREAD’s handling while maintaining superior accuracy is hard to deny. A well-balanced, fast handling accurate rifle such as the TREAD is a premium when moving dynamically during training, competition, or real-world situations.

All SIG M400 TREAD features are intended for maximizing effectiveness during a fight or realistic training on the range. The key component in a fighting rifle is reliability. No matter how accurate or powerful chambering a rifle is if it does not work 100 percent of the time it’s a liability. The TREAD is intended for serious practitioners who plan on using it for training or defense. The TREAD is equally at home in CQB encounters characterized by multiple rounds fired rapidly with distances measured in feet while still offering precision fire out to 350-400 yards. If ever you have envisioned a scenario responding to a bump or other commotion at night and have to grab a rifle and bandolier of magazines on the way to respond, then M400 TREAD is more than worthy of consideration of the DON’T TREAD ON ME nomenclature.

M400 TREADSpecs:

MSRP: $951.00

SIG Romeo Red Dots

SIG SAUER has entered the optics market in force over the last several years with several innovative designs and new takes on established concepts. SIG SAUER definitely now has “skin” in the optics game with numerous models in its product line-up. The use of red dots has become the norm on the battlefield, law enforcement, and personal defense. The SIG SAUER ROMEO4 and ROMEO5 are both red dot sights. The ROMEO4 would be considered the higher end version with the ROMEO5 still offering plenty of performance for individuals or departments who may have budgetary concerns — which most do.

Both the ROMEO4 and ROMEO5 sights are experiencing high demand from end-users who understand the performance benefits that a quality compact red dot sight offers. The “closed” design of the ROMEO4 and ROMEO5 limits the effect that weather or other environmental conditions may have on their performance. Rain, snow, debris etc cannot interfere with the red dot being projected on the lens enabling accurate shooting in any condition.

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The differences between the ROMOE4 and ROMEO5 consist of waterproofing levels, battery life, mounts, lens coating, housing material, and reticle selections. The ROMEO 4M tested features an IPX8 waterproofing rating (continuous submersion beyond 1 meter) while the ROMEO5 is IPX7 (immersion for 30 minutes at a depth of 1 meter). Each feature SIG SAUER’s MOTAC Technology. In short, MOTAC is motion-sensing technology, MOTAC immediately powers up illumination when it senses motion and powers down when it does not after a period of time. This serves to greatly extend battery life. Both ROMEOs reports 50,000+-hour battery life with the readily available CR2032 battery; which is side loading for quick replacement and does not require removal from the weapon negating the need for re-zeroing. Each sight has two-night vision compatible modes.

For more information, visit: www.sigsauer.com

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