Outfitters Score™
Excellent
Knights Armament scores as a top-tier build with premium pricing and most components included.
Our proprietary rating combines brand tier, price percentile within the caliber, feature completeness, barrel versatility, retailer availability, caliber practicality, and use-case fit.
Short Barrel: Verify Classification
This firearm has a barrel under 16 inches. It may be classified as an AR Pistol (with brace) or an SBR (with stock, NFA regulated). Check with the retailer to confirm classification before purchasing.
Description
KNIGHT'S ARMEMENT SR-15 KS-1 5.56 NATO SEMI-AUTO RIFLE The KS-1 features a 13.7" heavy profile ball-mill dimpled cold hammer forged barrel. This carbine allows a small, high efficiency suppressor to be attached and still maintain an overall length similar to a 10.3" barrel with a standard suppressor, but with significantly higher muzzle velocity. The heavy profile barrel resist heat-induced shift, maintaining point of impact throughout long-duration use. Ball mill dimpling aids in weight reduction while reducing heat-related shift effect that can be seen with traditional fluting. SPECS Barrel: 13.7", cold hammer forged, 1:7&rdquo Mfg: Knights Armament
Features
M Lok|Cold Hammer Forged
Full Specifications
Overview
| Brand | Knights Armament |
| Model | 121439 |
| SKU | 430115839 |
| Rifle Type | semi auto |
| Platform | AR15 |
| Caliber | 5.56 NATO |
| Chamber | 5.56 NATO |
| UPC | 819064019169 |
Barrel
| Barrel Length | 10.3" |
| Barrel Profile | heavy |
| Twist Rate | 1:7 |
Receiver
| Receiver Type | forged |
| Forward Assist | No |
| Dust Cover | No |
Handguard
| Handguard Type | m-lok |
| Free Float | No |
Muzzle
| Suppressor Ready | Yes |
Sights & Optics
| Optic Ready | No |
Dimensions & Weight
| Magazine Capacity | 30 rounds |
Finish
| Finish | black |
Compliance
| CA Compliant | No |
| Classification | Short Barrel: Verify Classification |
| NFA Item | Verify with retailer |
What's Included (Complete Rifle)
This is a complete, ready-to-shoot firearm.
Upper Receiver
Lower Receiver
forged
Barrel
10.3"
Bolt Carrier Group
Handguard
m-lok
Stock / BraceVerify with retailer
Grip
Trigger
Muzzle Device
Charging Handle
Gas Block
Gas Tube
Buffer Tube
Backup Iron Sights
Optic
Stock / Brace: Verify with retailer
We cannot confirm from available data whether this firearm includes a stock or brace. This distinction determines its legal classification.
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Manufacturer · Tier 1
See everything Knights Armament Company→
Build Guide
See our Suppressor-Ready Build→
State Check
This rifle has NFA or magazine considerations →
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 Ks-1 5.56 Nato Semi-Auto Rifle - Sr-15 Ks-1 5.56 Nato 13.7" Bbl (1)30rd Mag M-Lok Black
121439
Across 1 retailer
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