How to Choose the Right AR-15 Stock: Fixed vs Collapsible vs Adjustable
The stock you choose affects ergonomics, recoil management, and how naturally you shoot your AR-15. Modern stocks offer vastly more capability than their predecessors, but selection requires understanding your use case and how different stocks perform in various roles.
Fixed Stocks: Simplicity and Reliability
Fixed stocks are permanently attached and don’t telescope. They provide maximum rigidity and eliminate any potential movement during firing, which some precision shooters prefer. Fixed stocks also integrate better with body armor and plate carriers since there’s no telescoping movement. However, fixed stocks limit length-of-pull adjustment and require careful selection of the correct length for your proportions. A 7.75-inch pull is standard; some manufacturers offer extended versions. Fixed stocks work best for shooters with consistent shooting positions or those willing to commit to a specific fit.
Collapsible Stocks: The Standard Approach
Collapsible (telescoping) stocks dominate the market because they balance versatility with simplicity. They allow adjustment for different shooting positions, accommodate varying body armor, and let multiple shooters adjust for their dimensions. Standard collapsible stocks from manufacturers like Magpul, BCM, and Vltor provide 2-4 inches of adjustment. This flexibility means one rifle can be adjusted for bench shooting, standing, or shooting through a barricade without modification.
Length of Pull: Getting the Fit Right
Length of pull (LOP) is the distance from the trigger to the rear of the stock. This measurement varies based on arm length and shooting style. Most shooters fall between 12 and 13 inches. Proper length of pull ensures consistent cheek weld, allows natural trigger finger placement, and enables comfortable shouldering. If your LOP is too long, you’ll reach for the trigger awkwardly; too short and you’ll be cramped. Collapsible stocks solve this by allowing adjustment—usually with 4-5 positions separated by roughly 0.75 inches.
Cheek Weld and Sight Picture
Cheek weld—how your cheek contacts the stock—determines consistency with your optics. A proper cheek weld positions your eye at the correct height-over-bore for optimal sight picture and red dot/scope alignment. Some stocks include integrated riser/cheek rests. Premium adjustable stocks from Magpul (MOE, STR) and B5 Systems include slight angle and texture that assist cheek weld repeatability. If you’re upgrading an existing rifle, cheek weld compatibility with your optics matters significantly.
Buffer Tube and Locking Mechanisms
Collapsible stocks connect via buffer tube (receiver extension). Mil-spec tubes (1.168″ diameter) accept most standard stocks. Commercial-spec tubes (1.14″ diameter) require compatible stocks. Newer stocks use more secure locking mechanisms—lever locks, ratcheting systems, and tension screws—that prevent unintended collapse during use. Quality stocks maintain consistent lock strength across adjustment positions.
Materials: Polymer vs Metal
Modern polymer stocks perform excellently and cost less than metal. Magpul stocks use reinforced polymer that withstands years of service. Metal stocks (aluminum or steel) offer maximum durability but weigh more and cost significantly more. For most shooters, quality polymer stocks prove more practical. Specialized applications might warrant metal stocks—extreme cold climates where polymer becomes brittle, high-volume training where durability concerns mount, or operators who prefer metal aesthetics.
Recoil Management
Stocks don’t directly mitigate recoil like buffers do, but proper fit reduces felt recoil perception. A stock that fits your proportions naturally reduces tension required to hold the rifle steady, which improves recoil management and follow-up shot speed. Heavier stocks aren’t inherently better—proper fit matters more than weight.
Specialized Stock Types
Sniper-style stocks provide much longer length-of-pull for prone shooting and extreme adjustability. Competition stocks often feature ambidextrous adjustments and enhanced ergonomics. Lightweight stocks reduce overall weight for those carrying rifles extended distances. Collapsible stocks with storage compartments hold batteries, cleaning kits, or survival supplies. Consider your primary use case when evaluating specialized options.
Quick-Detach Considerations
Some stocks feature quick-detach mechanisms allowing complete stock removal and replacement. While this sounds convenient, it rarely justifies the complexity except for specialized applications. Standard collapsible stocks adjusted to your dimensions work better for most shooters.
Making Your Selection
Start by measuring your length of pull accurately. For most shooters, a quality collapsible stock from Magpul, BCM, or B5 Systems provides the flexibility you’ll appreciate. Adjust to the position that gives you natural cheek weld with your optics and comfortable trigger access. Verify your stock locks securely and doesn’t shift during normal handling. Unless you have a specific mission requirement, prioritize comfort and fit over exotic features. The best stock is the one that fits your dimensions and lets you shoot naturally without thinking about it.
