# Sig Sauer M400 SDI 5.56 NATO 16in Moss Green

**Brand:** SIG Sauer
**Category:** AR Style Rifles
**Caliber:** 5.56 NATO

## Specifications

- **Caliber:** 5.56 NATO
- **Barrel Length:** 16"
- **UPC:** 798681701216
- **SKU:** UCE3nP1Wq

## Description

The Sig Sauer M400 SDI is an AR-pattern semi-automatic rifle chambered in 5.56 NATO with a 16-inch barrel. It has a Cerakote Moss Green finish, a Magpul SL stock, and a factory-installed 2-stage Matchlite Duo trigger. The rifle ships with a 30-round magazine.

### Key Specifications
- **Brand**: Sig Sauer
- **Model**: M400 SDI
- **Caliber**: 5.56 NATO
- **Action**: Semi Auto
- **Capacity**: 30+1
- **Barrel Length**: 16 in
- **Color/Finish**: Moss Green (Cerakote)

### Detailed Features
- 16-inch threaded barrel
- Cerakote Moss Green finish
- Magpul SL stock
- Factory-installed 2-stage Matchlite Duo trigger
- Optics-ready configuration with 30-round magazine

## Frequently Asked Questions

**Q: What caliber is the Sig Sauer M400 SDI?**

A: The M400 SDI is chambered in 5.56 NATO.

**Q: Who makes the M400 SDI?**

A: It is made by Sig Sauer.

**Q: What type of firearm is the Sig Sauer M400 SDI?**

A: It is an AR-style semi-automatic rifle with a 16-inch barrel and a Magpul SL stock.

**Q: What is the barrel length of the M400 SDI?**

A: The M400 SDI has a 16-inch barrel.

**Q: How many rounds does the Sig Sauer M400 SDI hold?**

A: It ships with a 30-round magazine and has a 30+1 capacity.

**Q: Is the M400 SDI threaded?**

A: Yes, the M400 SDI has a threaded barrel.

**Q: Is the M400 SDI optics-ready?**

A: Yes, the M400 SDI is listed as optics-ready.

**Q: Where can I buy the Sig Sauer M400 SDI?**

A: Compare current vendor offers on this page.

## What Reviewers Say

*Quoted verbatim from YouTube reviews. Each link opens the video at the moment quoted.*

> It's got a take up on it is really short it's kind of it hits a wall.
>
> — [Sasquatch Mountain Project](https://www.youtube.com/watch?v=8BRnhHZteFw&t=303s)

> Screws would just hit the barrel so in order to get any of this to work on the M Block sections up here I needed to put washers down here a couple small washers.
>
> — [Sasquatch Mountain Project](https://www.youtube.com/watch?v=8BRnhHZteFw&t=650s)

> It was a joy to shoot everything everything worked no problems no problems at all.
>
> — [Sasquatch Mountain Project](https://www.youtube.com/watch?v=8BRnhHZteFw&t=739s)

## What Customers Say

*AI-generated insights from customer reviews*

The M400 SDI in Moss Green draws the same buyer profile as other SDI variants: owners who want a factory AR with a quality trigger without doing the work themselves. The Moss Green Cerakote is seen as a more subdued color option, and some owners specifically choose it over FDE for use in terrain where green tones blend better.

The 2-stage Matchlite Duo trigger is the recurring point of praise. Owners consistently describe the break as clean and the reset as short relative to mil-spec alternatives, and several note it as the primary reason they chose this rifle over an otherwise similar configuration.

Value opinions split predictably: some owners consider the complete package a fair deal; others note the same trigger performance is achievable for less if you build your own rifle or buy a standard model and upgrade. The Magpul SL stock is generally well-liked for stability, though some owners swap to an adjustable option for different shooting positions.

## Pricing

**12 offers available**

| Vendor | Price |
|--------|-------|
| Brownells | $1599.99 |
| Guns Com | $1599.99 |
| Kygunco Com | $1599.99 |
| Classicfirearms Com | $1599.99 |
| Buds Gun Shop | $1599.99 |
| Impactguns Com | $1599.99 |
| Grabagun Com | $1599.99 |
| Shootingsurplus Com | $1599.99 |
| Selwayarmory Com | $1599.99 |
| Primaryarms Com | $1599.99 |

*...and 2 more offers*

## Similar Products

- [Sig Sauer M400 Tread V2 5.56 NATO Rifle - Moss Green Precision Shooter](https://gunsnation.com/p/sig-sauer-m400-tread-v2-5-56-nato-rifle-moss-green-precision-shooter/UCE3nOy5s)
- [Sig Sauer M400 5.56 NATO 16in Black](https://gunsnation.com/p/sig-sauer-m400-5-56-nato-16in-black/UCE3nP81q)
- [Sig Sauer M400 5.56 NATO 16in Black](https://gunsnation.com/p/sig-sauer-m400-5-56-nato-16in-black/UCE3nOpT7)
- [Sig Sauer M400 Sentry 5.56 NATO 16in](https://gunsnation.com/p/sig-sauer-m400-sentry-5-56-nato-16in/UCE3nP5PM)
- [Sig Sauer M400 Forge 5.56mm NATO 16in Moss Green](https://gunsnation.com/p/sig-sauer-m400-forge-5-56mm-nato-16in-moss-green/UCE3nPCiE)
- [Sig Sauer M400 Tread 5.56 NATO 16in Black](https://gunsnation.com/p/sig-sauer-m400-tread-5-56-nato-16in-black/UCE3nP5Bi)

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*Data from [GunsNation](https://gunsnation.com)*