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Questions & Answers
Will this mount work with the 5.5X50 acog? Expert Answer

Yes, this mount would be compatible with that ACOG.

by Tom B, Gear Expert, November 19, 2021
Does it come with the ACOG mounting hardware? Expert Answer

This will include the rail base and the mounting screws. A riser will be sold separately.

by Kurt Colbourne, Gear Expert, March 19, 2021
Customer Reviews
Helpful Positive Review
AD-B3 QD Modular Base by Abez8888, Verified Owner, September 25, 2020
Changing the original Primary Arms 3x Prism Scope mount was a must. Needed the replacement mount to be QD and have a solid hold on top of my AR build. The AD-B3 Base met my requirements. It is a good solid mount. Comes with replacement screws. Fits P...
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1/1 found this helpful
Helpful Positive Review
Good Solid QDC Mount by SeaWolf, Verified Owner, September 4, 2018
Good solid mount. Comes with replacement screws. Fits Primary Arms AQ sight and probably others depending on hole spacing. Must replace foot on Primary Arms AQ sight, there is no upper Picatinny slotting. Note one set of screws hex slots are metric...
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1/1 found this helpful
Helpful Positive Review
High quality by Downsouth, September 20, 2018
Necessary part for the 5x primary arms acss scope, exact fit for the factory base, be sure to warm the factory screws a little with a heat gun when taking them off. High quality part have them on all my EQ thanks opticsplanet great price
1/1 found this helpful
Helpful Positive Review
Great Mount by Trav, Verified Owner, March 6, 2018
This mount worked perfect with the Primary Arms 2.5x prism scope. As always, the ADM mounts are great quality with a great price. I own 5 different ADM mounts and all top notch. The finish on these are outstanding and very easy to adjust for initi...
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1/1 found this helpful
Most Recent Reviews
American ingenuity by Agustin, Verified Owner, March 11, 2025
Great product, highly quality, light weight and easy to put on and take off. I definitely recommend this product.
Most Recent Reviews
Fantastic ACOG Mount by GeneralKenobiWins, Verified Owner, July 8, 2024
I recently got a 4x ACOG, but I could not stand the factory Trijicon mount. This mount has a single recoil lug, allowing for the mount to sit farther back on the rail of you're not running backup iron sights. The lockup is very firm. I tested return ...
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Read All 12 Reviews
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Product Info for American Defense Manufacturing AD-B3 Modular Base

LARGE MODULAR BASE OR FULL SIZE ACOG MOUNTimage

Specifications for American Defense Manufacturing AD-B3 Modular Base:

Manufacturer: American Defense Manufacturing
Fabric/Material: 6061-T6 Aluminum
Weight: 3 oz
Condition: New
Finish: T3 Mil-Spec Anodize

Package Contents:

  • American Defense Manufacturing AD-B3 Modular Base

American Defense Manufacturing AD-B3 Modular Base Orderable Models

List of Orderable Models

  • American Defense Manufacturing AD-B3 Modular Base, Standard Lever, Black, AD-B3 STD , MPN: AD-B3-STD , UPC: 818503010040 , Code: 26S-SCM-ADB3-AD-B3-STD
  • American Defense Manufacturing AD-B3 Modular Base, Tactical Lever, Black, AD-B3 TAC R , MPN: AD-B3-TAC , UPC: 818503012792 , Code: 26S-SCM-ADB3-AD-B3-TAC
  • American Defense Manufacturing AD-B3 Modular Base, Tactical Lever, Flat Dark Earth, AD-B3 TAC R FDE , MPN: AD-B3-FDE-TAC , UPC: 818503012815 , Code: 26S-SCM-ADB3-AD-B3-FDE-TAC
  • American Defense Manufacturing AD-B3 Modular Base, Standard Lever, Flat Dark Earth, AD-B3 STD FDE , MPN: AD-B3-FDE-STD , UPC: 818503010057 , Code: 26S-SCM-ADB3-AD-B3-FDE-STD

American Defense Manufacturing AD-B3 Modular Base Unavailable & Discontinued Models

List of Unorderable Models

  • Open Box, Dealer Demo, American Defense Manufacturing AD-B3 Modular Base, Standard Lever, Black, AD-B3 STD , MPN: AD-B3-STD-DMO , Code: 26S-SCM-ADB3-AD-B3-STD-DMO
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