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AR-15 Parts

Everything for building, upgrading or maintaining an AR-15: uppers, bolt carrier groups, barrels, handguards, stocks, triggers, grips, charging handles and magazines. We list over 3,100 AR-15 parts from Magpul, Strike and LBE Unlimited.

Building or upgrading an AR-15

Most AR-15 parts follow mil-spec dimensions, but a few do not. Buffer tubes come in mil-spec and commercial diameters, so match your stock to your tube. Gas systems come in pistol, carbine, mid-length and rifle lengths, and the gas block has to match your barrel's journal diameter.

If you are building from a stripped lower, a lower parts kit, buffer tube kit and stock finish the lower. On the upper, match the barrel, gas system and handguard length before you order.

AR-15 Parts FAQ

Will these parts fit an AR-10 or .308 AR?

Most will not. AR-10 and LR-308 rifles use larger receivers, bolts and magazines. Look for AR-10, LR-308 or .308 in the title.

What is the difference between 5.56 and .223 Wylde?

A .223 Wylde chamber safely fires both 5.56 NATO and .223 Remington with good accuracy, and so does a 5.56 chamber. A .223 Remington chamber should not fire 5.56.

Shop related: Gun Parts · AR-15 Magazines · Red Dots & Holographic Sights · Rifle Ammo

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