M110A1 CSASS
Heckler & Koch · Carbine · In Production · 2016
Also known as: CSASS, Compact Semi-Automatic Sniper System, HK G28E-SDM
Overview
The M110A1 CSASS is a semi-automatic carbine chambered in 7.62x51mm NATO, produced by Heckler & Koch GmbH since 2016. Featuring a 20-round magazine capacity, this carbine offers generous firepower for duty use and home defense.
Specifications
| Weight (empty) | 3810 g (134.4 oz) |
| Weight (loaded) | 4500 g (158.7 oz) |
| Overall Length | 914 mm (35.98") |
| Barrel Length | 406 mm (15.98") |
| Action Type | Gas Operated Short Stroke Piston |
| Firing Mechanism | Hammer Fired |
| Trigger Type | Two Stage |
| Trigger Pull | 18 N (4.0 lbf) |
| Magazine Capacity | 20 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 783 m/s (2569 fps) |
| Muzzle Energy | 2975 J (2194 ft·lbf) |
| Effective Range | 800 m (875 yd) |
| Maximum Range | 3600 m (3937 yd) |
| Barrel Rifling | Right Hand |
| Rifling Twist | 279 mm (10.98") |
| Number of Grooves | 4 |
| Frame Material | Aluminum Alloy |
| Barrel Material | Steel |
| Stock Material | Polymer |
| Finish | Hard Anodized |
Calibers
- 7.62x51mm NATO · primary · 7.62x51mm NATO — also known as .308 Winchester, 7.62 NATO
Features
- Firing modes: Semi Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety Selector, Firing Pin Safety
- Features: Short Stroke Gas Piston, Free Floating Barrel, Match Grade Barrel, Chrome Lined Barrel, Picatinny Rail, Adjustable Stock, Quick Detach Suppressor, Geissele Trigger, M Lok Handguard, Ambidextrous Controls
Service history
Operators
- United States Army · adopted 2016 · as M110A1
- United States Special Operations Command · adopted 2016
Production
Estimated total produced: 5,180 · Production years: 2016-present
Initial contract for 5,180 rifles for US Army, with potential for follow-on orders
Origin
Country of origin: Germany
Notes
The M110A1 CSASS competed against the Knights Armament M110K1 and Remington SDMR-C in the Army's Compact Semi-Automatic Sniper System program. H&K won the contract in March 2016, with the rifle entering service in 2017. The HK417-based platform uses a short-stroke gas piston system derived from the G36, providing superior reliability in adverse conditions compared to direct impingement systems. The 16-inch barrel reduces velocity slightly compared to the M110's 20-inch barrel but significantly improves maneuverability. The rifle features ambidextrous controls, tool-free barrel removal, and over-the-beach capability for immediate firing after water exposure. Standard issue includes the OSS suppressor for reduced signature and improved shooter comfort.
Background
The M110A1 marked a shift in US Army sniper doctrine toward lighter, more compact semi-automatic platforms for squad-level designated marksmen. The rifle's development emphasized compatibility with advanced ammunition types that can defeat modern body armor, addressing lessons learned from combat in Iraq and Afghanistan where traditional 7.62 NATO ball ammunition proved inadequate against some threat levels.