Outfitters Score™
Excellent
Sig Sauer, Inc. scores as a top-tier build with excellent value pricing and a full feature set.
Our proprietary rating combines brand tier, price percentile within the caliber, feature completeness, barrel versatility, retailer availability, caliber practicality, and use-case fit.
Description
The M400 TREAD is an optics ready, aluminum frame rifle. TREAD features a 16" stainless steel barrel with a free-floating M-LOK handguard, a single-stage polished/hard-coat trigger, ambidextrous controls, a Magpul(TM) SL-K 6 position telescoping stock, a mid-length gas system, and is available in 5.56 NATO. Other TREAD branded accessories (purchased separately) include: M-LOK handguard with lightening cuts to reduce weight, available in 13" and 15" lengths; 3 chamber compensator; Ambidextrous charging handle made of aircraft grade aluminum and a dual roll pin design; ROMEO5 optic featuring a 2MOA dot with ten illumination settings, MOTAC Mfg: Sig Sauer, Inc.
Features
Free Float|M Lok|Ambidextrous|Ambi
Full Specifications
Overview
| Brand | Sig Sauer, Inc. |
| Model | RM400-16B-TRD |
| SKU | 100032508 |
| Rifle Type | semi auto |
| Platform | AR15 |
| Caliber | 5.56 NATO |
| Chamber | 5.56 NATO |
| UPC | 798681597765 |
Barrel
| Barrel Length | 16" |
| Barrel Finish | stainless |
Gas System
| Gas System Length | mid-length |
Receiver
| Forward Assist | No |
| Dust Cover | No |
Handguard
| Handguard Type | m-lok |
| Handguard Material | aluminum |
| Free Float | Yes |
Furniture
| Stock Type | collapsible |
Trigger
| Trigger Type | single-stage |
Muzzle
| Muzzle Device | compensator |
| Suppressor Ready | No |
Sights & Optics
| Sights Included | none |
| Optic Ready | Yes |
Dimensions & Weight
| Magazine Capacity | 30 rounds |
Finish
| Finish | black |
Compliance
| CA Compliant | No |
| Classification | Rifle |
| NFA Item | No |
What's Included (Complete Rifle)
This is a complete, ready-to-shoot firearm.
Upper Receiver
Lower Receiver
Barrel
16"
Bolt Carrier Group
Handguard
m-lok, Free Float
Stock
collapsible
Grip
Trigger
single-stage
Muzzle Device
compensator
Charging Handle
Gas Block
Gas Tube
mid-length-length
Buffer Tube
Backup Iron Sights
Optic
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Manufacturer · Tier 1
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State Check
This rifle has NFA or magazine considerations →
Swiss-origin firearms giant. The M400 and MCX platforms compete in the premium space, and Sig won the US Army NGSW rifle contract with the XM7.
View brand profile →M400 Tread 5.56x45 Nato Semi-Auto Rifle - M400 Tread 5.56x45 Nato 16" Bbl (1)30rd Mag Black
RM400-16B-TRD
Built Right for an Entry-Level AR-15
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