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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Glock magazines interchange more than most platforms — but only within the right caliber and frame family, and only in one direction. Here's exactly which Glock mags fit which Glocks. The Two Rules That Govern Everything Caliber must match the magazine body. 9mm and .40 S&W magazines are not interchangeable — the feed lips and body width differ. Bigger frame ma …
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Open vs enclosed emitter is one of the few red dot decisions where the failure modes are physical and obvious. Lint clogs an open emitter. Sweat fogs the front lens. Rain pools across the LED housing. Snow blocks the dot until the pistol warms up. None of those are theoretical — they happen to carry guns sitting in waistbands and pockets all day. Enclosed emitter optics s …
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