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Home Gunsmith Tools Rifle Tools Bench & Vise Blocks GEISSELE AUTOMATICS AR-15/M4 REACTION BLOCK Support
Upgrade your AR-15 assembly with the Geissele Reaction Block! 🛠️ Enjoy a stable platform for easy buffer tube installation and lower receiver operations.

GEISSELE AUTOMATICS AR-15/M4 REACTION BLOCK - GEISSELE AUTOMATICS AR-15/M4 REACTION BLOCK(MIL-SPEC BUFFER TUBE ONLY)

854014005984 100016578

Top takeaways

  1. The Geissele Reaction Block is specifically designed for assembling AR-15 lower receivers with MIL-SPEC buffer tubes.
  2. It allows the lower receiver to be rotated in 90-degree increments for ease of access by simply adjusting the nylon screws.
  3. Provides a stable platform for lower receiver operations and simplifies the installation of the buffer retainer nut.

Attributes

  • Weapon type: AR-15
  • Delivery weight: 0.703kg
  • Shipping height: 76mm
  • Shipping width: 121mm
  • Shipping length: 203mm
  • UPC: 854014005984

Item details

Made in USA
  • Specifications:
  • Make: AR-15
254.9 254.9 1 GBP
254.9 GBP £254.90

Prices inclusive of duty & VAT.

Product no.: 100016578

Mfr. No.: 05-314

854014005984 The Geissele Reaction Block is designed to aid in the assembly of lower receivers. Once the armorer has installed the buffer tube onto the lower; the buffer tube and lower receiver assembly can be slid into the Reaction Block at the 12, 3, 6 and 9 o’clock positions. This allows the armorer to rotate the lower in 90 degree increments in the block simply by loosening the provided nylon screws, removing the lower, and sliding it back in at the desired orientation. The Reaction Block provides an ultra-stable platform for performing an array of lower receiver operations, as well as making the installation of the buffer retainer nut quick and easy. All while keeping both hands of the armorer free to work, saving both time and frustration.
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  • Specifications:
  • Make: AR-15

Description:

The Geissele Reaction Block is designed to aid in the assembly of lower receivers. Once the armorer has installed the buffer tube onto the lower; the buffer tube and lower receiver assembly can be slid into the Reaction Block at the 12, 3, 6 and 9 o’clock positions. This allows the armorer to rotate the lower in 90 degree increments in the block simply by loosening the provided nylon screws, removing the lower, and sliding it back in at the desired orientation. The Reaction Block provides an ultra-stable platform for performing an array of lower receiver operations, as well as making the installation of the buffer retainer nut quick and easy. All while keeping both hands of the armorer free to work, saving both time and frustration.

Top takeaways

  1. The Geissele Reaction Block is specifically designed for assembling AR-15 lower receivers with MIL-SPEC buffer tubes.
  2. It allows the lower receiver to be rotated in 90-degree increments for ease of access by simply adjusting the nylon screws.
  3. Provides a stable platform for lower receiver operations and simplifies the installation of the buffer retainer nut.

Attributes

  • Weapon type: AR-15
  • Delivery weight: 0.703kg
  • Shipping height: 76mm
  • Shipping width: 121mm
  • Shipping length: 203mm
  • UPC: 854014005984

Item details

Made in USA

Customers reviews

Customer ratings (2)

5 / 5
Definitely recommended

Brownells USA Geissele Reaction Block for "Mil-Spec" 02/05/2017

I purchased a Geissele reaction block when Brownells was offering a sale on all Geissele products. I'm a late comer to the AR 15 format / style rifle. Been a bolt action rifle guy my whole life until recently. I decided, after much research and comparison shopping, to invest in top quality tools. My first AR 15 build went flawlessly using Geissele's reaction rod and block. Very well thought out designs and made to last. The reaction block design allows you to rotate the buffer tube in 90 degree increments to accommodate what you need to do. Will make maintenance on my lower receivers and barrel swapping a much easier task now that I have the right tools. Both the reaction rod and the block fit nicely on a 4" bench vise. Great products from a US company. Highly recommend.

Definitely recommended

Brownells USA Another Solid Product from Geissele 17/08/2016

I've used it countless times now building lowers, installing/changing end plates, staking castle nuts, and all other work that needs to be done to the lower if you wish. The three bolts at the top really lock the receiver extension in place have never marred the finish. Worth every penny.

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