Sanders Armory 18” MATCH GRADE 5.56 NATO 416R Stainless Steel Barrel with a Tapered HBAR profile with 5R Rifling and a 1:8 Twist Rate. This Match Grade 5.56 NATO barrels includes M4 Feed ramps, a RIFLE-Length Gas System, 750 Gas Block Acceptance and is AIR GAUGE Tested. The barrel is threaded for a Flash Hider or Muzzle break with 1/2 x 28 threads. Weight: 1.8 Pounds
U.S. made and manufactured to MIL-SPEC specifications exceeding the ISO-9002 Quality Standard. Provided with a Limited Lifetime Manufacturer Warranty against manufacturers defects.
- Brand: Sanders Armory
- Barrel Caliber: 5.56 NATO
- Barrel Length: 18″ Inch Match Grade
- Twist Rate: 1:8 Twist
- Rifling process: 5R Button Rifled
- Barrel Concentricity held to .002
- Rifling Test: Air Gauged
- Material: 416R Stainless Steel
- Finish: Polished Stainless Steel
- Inside Finish: Polished Stainless Steel
- Profile: Light Weight Contour
- Gas System Length: Rifle-length Gas Tube
- Diameter Gas Block: .750 Gas Block
- Gas Block Dimple: Yes
- Barrel Crown Thread Pattern: 1/2 X 28 Thread Pitch
- Barrel Crown: Single Point Cut Polished 11-degree Target Crown
- Extension: M4 Nitride Coated
- Feed Ramps: M4 cut Barrel extension
- Weight: 2 Lbs 6oz.
What is 5R Rifling?
Retired Army man, Barrett “Boots” Obermeyer developed 5R rifling as a gunsmith in his families store and holds a High Master Classification in both high-power rifle disciplines, is a Distinguished Rifleman and has won numerous shooting awards at both state and national levels.
The best definition comes from “Boots” himself …
“5R is the form of rifling I developed for use in most target barrels and in many sporting barrels,” he explained. “These barrels have 5 grooves, and the lands have angular sides. I have observed that bullet jackets will deform such that they remain closer to the R-form lands than they will to the sharp-edged lands present in conventional-style rifling. This reduces powder fouling at the corner of the grooves. The angled form of the lands also helps to reduce jacket failures in quick-twist barrels.”
The diagram above of rifling profiles shows the difference between traditional rifling (top) and 5R rifling (bottom). Note that the edges of 5R are not square (they don’t cut into bullet jacket as much) and that with 5R, the lands are opposite of grooves while with traditional rifling, lands are opposite lands and grooves are opposite grooves.
NO shipping to District of Columbia (Washington, D.C.); Massachusetts; Connecticut; Chicago; Cook County, Deerfield, Highland Park or Aurora Illinois; New Jersey; New York; Puerto Rico; Hawaii; Alaska or Canada! NO international shipping all must be within the 48 Contiguous United States! NO APO/PPO/FPO’s.