DD4 RIS III 11.5-inch on an LWRC IC Ambi Lower
$4,152.546 parts
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DD MK18 FDE SBR on a Griffin MK2 Terra Brown Lower
$1,774.003 parts
BCM MK2 16-inch on a Rock River Lower with Sig Tango MSR
$1,823.368 parts
6mm MAX Mk12-Style SPR on BCM MK2 and LWRCI Receivers
$3,672.369 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.
80% Lowers Explained: What They Are and the Law in 2026
What an 80% lower is, why federal law now treats many as firearms, what the 2025 Supreme Court ruling and the August 2026 court …
How to Build an AR-15 Pistol: Parts, Rules and Brace Options
What makes an AR-15 a pistol, the parts you need, what changed for stocks and braces in 2026, and what to check before you …
.308 Ballistics Chart: Velocity, Drop and Energy for the AR-10
Published .308 velocity, energy and drop for 150 and 168 grain loads, and what a 16 to 20 inch AR-10 barrel gives up compared …