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Rainier Arms Select 5.56 NATO M16A1 Barrel - 20"


In stock

Satisfaction Guarantee

We are so confident in our barrels that we offer a 100% money back guarantee within 90 days of purchase.  If our barrels don’t meet or exceed your expectations, for any reason, return it for a full refund.


Many have asked us to build a barrel with the same workmanship as our Match barrels while keeping it more affordable. We are able to reach our goal by sourcing a very high end barrel blank at an affordable price. We start off using a high precision match blank in 1:7 twist, use a 5 groove polygonal rifling, machine it to the highest quality and matched with our limited-life time warranty, you have a barrel that is the best value, hands down, in the industry.



  • Stainless Steel Blank
  • Length: 20"
  • Twist: 1:7
  • Thread Pitch: 1/2 X 28
  • .625 Gas Block Seat
  • 5.56 NATO Chamber
  • 5 groove polygonal rifling
  • Rifle Gas System (Gas Tube not Included)
  • M4 Feed Ramps
  • M16A1 Contour
  • Nitride Finish
  • Weight: 1 lb 13.9 oz


Our Craftsmanship Guarantee

Rainier barrels are meticulously designed and machined by precision gunsmiths. Our barrels are turned the same way true artisans have made premium rifle barrels for over a century. Each barrel has hand-cut chambers and crowns with the attention to detail that can only come from highly trained human intervention. While most companies strive for faster production time to cut cost, we strive for perfection. There are no shortcuts with our barrels, period.

We will go toe to toe with anyone and win.


More Information
Product Type Barrel
Manufacturer Rainier Arms, LLC
Gas Block Diameter .625"
Thread Pitch 1/2x28
Twist Rate 1:7
Color Black
Gas Length Rifle
Finish Nitride
Barrel Length 20"
Caliber 5.56 NATO

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