Ruger American Rimfire – Model 8378 – 22 LR

Precision Rimfire Target Platform

The Ruger American Rimfire in 22 LR is engineered for competitive accuracy and refined ergonomics. Featuring a two-tone speckled black/brown laminate stock with adjustable comb and length of pull, this rifle blends precision with custom comfort. The flush-mounted lower M-LOK® rail and QD sling points enhance modularity and handling.

Barrel & Trigger Excellence

Equipped with a 560mm cold hammer-forged bull barrel and thread pattern 1/2"-28, it includes a knurled thread protector and is free-floated by Ruger’s Power Bedding™ system. The Marksman Adjustable™ trigger (1360–2270g) ensures crisp, reliable shot release.

Design Features & Compatibility

The 13.5" adjustable length of pull, extended magazine release, and 60° bolt throw make handling smooth and intuitive. Includes a BX-1 rotary magazine and is compatible with all 10/22® magazines. Factory-installed one-piece aluminum Picatinny rail allows optic mounting out of the box.

Technical Specifications

• Caliber: 22 LR
• Barrel Length: 560mm
• Thread Pattern: 1/2"-28
• Twist: 1:16" RH
• Capacity: 10
• Magazine Type: BX-1 rotary (flush-mounted)
• Weight: 3630g
• Overall Length: 1030mm
• Length of Pull: 343mm (adjustable)
• Grooves: 6
• Material: Alloy Steel
• Finish: Matte Blued
• Sights: None – Picatinny scope base installed
• Includes: BX-1 magazine, sling swivel studs, M-LOK® rail, QD points