Outfitters Score™
Excellent
Knights Armament scores as a top-tier build with premium pricing and a bare-bones configuration.
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 Knights Armament SR-15 E3 Mod 2 Series rifle offers AR aficionados and first-time owners with a high-quality, semi-auto rifle platform that enables users to do everything they need, whether it's precision shooting or close-range rapid fire. The Knights Armament SR-15 E3 Mod 2 Series rifle features the company's military-spec 5.56 NATO barrel, which is surrounded by the company's URX4 handguard, fully compatible with all M-LOK accessory attachments. Other improved features include an enhanced bolt-lug design that aims at improving service life, as well as a two-stage drop-in trigger that allows for precision shooting. Direct-impingement action Barrel leng Mfg: Knights Armament
Features
M Lok
Full Specifications
Overview
| Brand | Knights Armament |
| Model | 31900 |
| SKU | 100025326 |
| Rifle Type | semi auto |
| Platform | AR15 |
| Caliber | 5.56 NATO |
| Chamber | 5.56 NATO |
| UPC | 819064015598 |
Receiver
| Forward Assist | No |
| Dust Cover | No |
Handguard
| Handguard Type | m-lok |
| Handguard Length | 4" |
| Free Float | No |
Trigger
| Trigger Type | two-stage |
Muzzle
| Suppressor Ready | No |
Sights & Optics
| Optic Ready | No |
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
Bolt Carrier Group
Handguard
m-lok, 4"
Stock
Grip
Trigger
two-stage
Muzzle Device
Charging Handle
Gas Block
Gas Tube
Buffer Tube
Backup Iron Sights
Optic
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Manufacturer · Tier 1
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Build Guide
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Home of the SR-15 and SR-25 platforms. One of the original AR innovators, with deep military roots and a premium price tag to match.
View brand profile →Sr-15 E3 Mod 2 M-Lok 5.56 16"
31900
A True Do-it-All AR-15
Across 1 retailer
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