Buyers ask this exact question before every aftermarket Glock 19 slide purchase: Gen 3, Gen 4, or Gen 5 — what actually fits? The short answer is that Gen 3 slides fit Gen 1 through Gen 3 frames, Gen 4 slides fit Gen 4 frames, Gen 5 slides fit Gen 5 frames, and cross-generation combinations range from “mounts with caveats” to “doesn’t fit” &m …
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Pick the wrong gas system length for your barrel and the rifle either short-strokes (won't cycle) or over-pressures (battering the bolt). This guide matches gas length to barrel length so you buy an upper and handguard that actually run together — no assembly walk-through, just what fits. The Four Gas System Lengths The "gas system length" is the distance from the chamber …
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If you bought a free-float handguard and then discovered it didn't come with an installation tool — or that the barrel nut doesn't work with your current upper — you've encountered one of the most confusing but easily solved problems in AR-15 building. This article covers the mechanical side: what barrel nut types exist, how they differ, what you need to install ea …
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