BCM Dark Bronze 14.5-inch on a Spikes Lower
$1,829.7410 parts
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First Build: Geissele Upper on an ADM UIC Ambi Lower with OCL Polonium K
$2,160.3714 parts
BCM 14.5-inch SOCOM Upper with DD RIS II on an LMT MARS-L Lower
$4,067.4214 parts
PSA 14.5-inch Quad Rail on an FDE Aero M4E1 Lower
$707.625 parts
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Geissele Super Semi-Automatic Enhanced (SSA-E) Trigger- 05-160
$245.00 at Brownells · 8 stores
In stock
Aero Precision AR-15 M4E1 Stripped Lower Receiver - Black
$124.99 at Aero Precision · 2 stores
M16 Bolt Carrier Group Black
$211.26 at Brownells · 6 stores
In stock
AR-15 Talon Safety Selector Ambidextrous Black
$64.95 at Brownells · 7 stores
In stock
AR-15 Raptor Ambidextrous Charging Handle Black
$104.95 at Brownells · 8 stores
In stock
H1 Super 42 Braided Wire Buffer Spring And Buffer Combo, H2
$108.99 at Kentucky Gun Co · 8 stores
In stock
MOE K2 Grip Polymer Black
$14.99 at GunMag Warehouse · 9 stores
In stock
B5 Systems SOPMOD Bravo Stock - Black BRV-201-01
$54.19 at Palmetto State Armory
From the blog
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How to Build an AR-15: Parts List, Tools & Steps
Everything you need to build an AR-15: parts list with current prices, tools, and step-by-step photos for the lower and upper receiver.
What Is .308? Caliber, Range and What It's Good For
.308 Winchester explained: what caliber it is, the energy it keeps at 500 yards against 5.56, 7.62x51 vs .308, and what it is good …
What Does AR Stand For? (Hint: Not "Assault Rifle")
AR means ArmaLite Rifle. The short history of the AR-15 from ArmaLite to Colt, and why "assault rifle" is the wrong expansion.
5.56 vs .223 vs .223 Wylde: Can You Mix Them? (SAAMI 2026)
Can you shoot 5.56 in a .223 rifle? What SAAMI says about each chamber, why .223 Wylde exists, and what caliber 5.56 really is.