Aero M4E1 11.3-inch BA Hanson Suppressed Build on a PSA Stealth Lower
$3,002.4522 parts
Build your own AR-15
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Pick a part for each slot in our free AR-15 builder, check that it all fits, and see the best price across stores for every part.
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Parts builders pick most
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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
B5 Systems SOPMOD Bravo Stock - Black BRV-201-01
$58.99 at Palmetto State Armory
H1 Super 42 Braided Wire Buffer Spring And Buffer Combo, H2
$114.00 at Brownells · 7 stores
In stock
AR-15 Raptor Ambidextrous Charging Handle Black
$104.95 at Brownells · 7 stores
In stock
M-LOK Bcmgunfighter Short Vertical Grip Polymer Black
$18.95 at Brownells · 6 stores
In stock
M16 Bolt Carrier Group Black
$211.26 at Brownells · 5 stores
In stock
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 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 …
6.5 Grendel Bolt: Why It Needs Its Own Bolt Carrier Group
Why a 6.5 Grendel AR-15 needs a Grendel bolt, what else changes from 5.56, and why 6mm ARC uses the same bolt.