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Rifle Kit, 20", A3, 1-7" twist, GAS BLOCK

  • Model: AR-RK20-GB-7
  • 55 Units in Stock


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This COMPLETE PARTS KIT (less stripped lower receiver) has the following standard features:

M4 Feed Ramp barrel extension
T-Marked forged upper receiver
1-7" twist, 6 grooves, right hand
5.56mm chamber (shoot either 5.56mm or .223)
11595E (SAE 4150) Barrel steel
Manganese Phosphate finish barrel

This 5.56mm caliber barrel is 20" long, threaded the standard 1/2 x 28 tpi, and has an A2 flash hider with the correct crush washer, and a correctly sized gas port for reliable function. The barrel is machined from chrome-moly, high vanadium steel and hardened to a U.S. government Mil-spec of Rc 26-32. The barrel, and all external steel parts, are manganese phosphate finished IAW of Mil-STD-171, the U. S. government's recommended protective finish for steel. This finish not only looks great, it affords complete corrosion protection. These barrels are of A2 or "Government" contour (tapered under the handguards, .750 under the front sight base) which alleviates barrel whip and enhances accuracy in semi auto fire and helps dissipate heat.  The barrel is button rifled with 6 grooves, right hand, 1 / 7" twist.  The 1/” twist is best for bullets 62 gr. and heavier.

The barrel is mounted on a FORGED A3 upper receiver with built in Mil-spec M1913 Picatinny accessory rail with the correct rail numbers engraved, made from certified 7075T6511forgings, hardcoat anodized IAW Mil Spec A8625, Type III, Class II, black per No. 37038, Table IX with nickel acetate seal, as per the Mil-spec. The upper features a forward assist and hinged ejection port cover.

The barrel features a hardcoat anodized, machined aircraft aluminum, 4 position gas block.  This gas block has 4 M1913 Picatinny rails for easy mounting of sights and/or accessories. Also included are A2 rifle handguards with aluminum heat shields.

The buttstock is a 6 position telescoping stock designed for a stable cheek weld in any position.  It features a paddle release, rubber butt pad and is of standard A2 length when fully extended.  It also comes STANDARD with a Double sling hook locking plate.

All semi auto lower receiver parts are INCLUDED as well as semi auto bolt, carrier, and charging handle. The upper is COMPLETELY ASSEMBLED. Each and every part to the gun is included EXCEPT the stripped lower receiver! (A complete firearm is pictured, the lower receiver, sights, vertical grips, etc. and magazine, even though shown in the picture, are NOT included).

If you would like to order a removable carry handle with match A2 sights installed, order one here:

Don't forget the Mil Spec Aluminum, 30 round magazines:

If you would prefer a Mil Spec A2 (solid) stock, simply order item  "AR-A2buttsub" on the SAME order as this kit. Here is the link:

PLEASE NOTE:  For CHROMED barrel interior and chamber, You must ACTUALLY Order part # AR-CHROME on your web order form, if you do not see it and it does not charge you $50 on your form, you have not ordered it and will not receive a chromed barrel. Do NOT just put it in the special instructions. Here is the link:

Since this parts kit does not include the receiver, no FFL is required. Like all of our AR parts kits, this is MADE IN USA!

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This product was added to our catalog on Saturday 30 April, 2016.

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