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Seekins Precision PRO Series 8" SPROv3 Complete Upper Assembly (300 Blackout)

  • Seekins Precision PRO Series 8" SPROv3 Complete Upper Assembly (300 Blackout)
  • Seekins Precision PRO Series 8" SPROv3 Complete Upper Assembly (300 Blackout) - Parts
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Seekins Precision PRO Series 8" SPROv3 Complete Upper Assembly (300 Blackout)

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$839.00 $799.00
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MPN: 0011100057


  • Specifically design for use with a suppressor (suppressor not included)
  • Caliber: .300 Blackout
  • Finish: Type III Class 2 Hardcoat Anodized Finish
  • Upper Receiver: Seekins Precision iRMT-R Billet Upper - CNC Machined from solid 7075-T6 Billet aluminum
  • Handguard: 12" Seekins Precision MCSR KeyMod hand guard
  • M4 Feed Ramps: Yes
  • Muzzle Device: None
  • Barrel: 8” 1:7 Match Grade 300BLK Barrel
  • Muzzle Thread Pattern: 1/2"-28
  • Gas Block: Seekins Precision Melonited Adjustable Gas Block
  • Gas Tube: Pistol-Length Melonited Gas tube
  • Bolt Carrier Group: Mil-Spec M16 Bolt Carrier Group
  • Charging Handle: Strike Industries ARCH-EL Charging Handle


  • Weight: 3 lb. 6.1 oz.
  • Length: 20"

*This upper receiver assembly has a barrel that is shorter than 16". This upper is only for use on AR pistol lower receivers and NFA registered Short-Barreled Rifle (SBR) lower receivers. All NFA laws apply!


If you’re looking for a complete .300 Blackout AR upper which is compatible with a suppressor, consider the SPROV3 by Seekins Precision. Seekins Precision is committed to producing high-quality parts for the AR platform. Begun in 2005 by an avid hunter and firearms user, the company maintains its status as one of the leading providers of firearm parts to this day.

The PRO Series 300 Blackout SPROV3 upper includes the iRMT-R upper receiver. The iRMT-R is CNC-machined from 7075-T6 billet aluminum for maximum strength. The handguard mount is machined directly into the upper itself to strengthen the receiver and to provide extra stability for use with the included 12” MSCR KeyMod handguard. Both the receiver and the handguard feature a Type III Hardcoat Anodized matte black finish.

Also included with this Seekins Precision upper is an eight-inch 300 Blackout match grade barrel. All the barrels produced by Seekins are machined from the finest steel blanks and are given no less than four inspections to ensure their quality and accuracy.

The SPROV3 also includes an adjustable gas block that allows you to tune your gas system for maximum performance. The gas system components are all coated with Melonite to resist corrosion and wear. Melonite coatings are also easier to clean than the standard Parkerized finishes.

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  1. Seekins Precision PRO Series 8" SPROv3 Complete Upper 5 Star Review

    Posted by on 12th Dec 2015

    Anything Glen Seekins makes is 100% good to go. His product line thankfully continues to group and each new addition is well though out and top rate.
    His new PRO Series 8" SPROv3 Complete Upper Assembly in my opinion couldn't be improved upon in any way. It has run flawlessly and the accuracy is crazy from a 8 inch barrel. You can custom tune to any load with the easy to get to adjustable gas block. Glen you did good again.

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