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 · 9 stores
In stock
Aero Precision AR-15 M4E1 Stripped Lower Receiver - Black
$124.99 at Aero Precision · 3 stores
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 · 7 stores
In stock
M16 Bolt Carrier Group Black
$211.26 at Brownells · 6 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
$58.99 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.
AR-15 Buffer Weights Explained: Carbine vs H1 vs H2 vs H3
What carbine, H1, H2 and H3 buffers weigh, which one your rifle needs, and how to read your ejection pattern to tune it.
What Size Gas Block Do I Need for My AR-15?
The four common gas block sizes, which barrels use each, how to measure your barrel's journal, and low-profile, adjustable and pinned blocks.
300 Blackout BCG and Magazines: What Works?
Why your 5.56 bolt carrier group and lower work with 300 Blackout, when magazines matter, and the one safety rule every 300 Blackout owner …