Absolute vs 1/3rd Co-witness... Does it matter?

Published on September 5, 2015
Duration: 10:41

This guide explains the differences between absolute and lower 1/3rd co-witness setups for red dot sights on rifles, as detailed by an expert from Regular Guy Training LLC. It covers how each setup affects sight picture, accessory compatibility, night vision use, and emergency optic failure scenarios, emphasizing the practical advantages of the lower 1/3rd configuration for tactical applications.

Quick Summary

Lower 1/3rd co-witness is often preferred for tactical rifles because it provides a cleaner sight picture with less obstruction. This setup also offers better clearance for accessories like lasers and is more compatible with night vision devices for passive aiming, unlike absolute co-witness.

Chapters

  1. 00:00Introduction to Co-witnessing
  2. 00:33Absolute Co-witness Explained
  3. 00:55Lower 1/3rd Co-witness Explained
  4. 02:31Advantages of Lower 1/3rd Co-witness
  5. 03:50Night Vision and Passive Aiming
  6. 05:00Emergency Sight Techniques
  7. 07:24Height Over Bore and Holdovers

Frequently Asked Questions

What is the difference between absolute and lower 1/3rd co-witness?

Absolute co-witness aligns iron sights perfectly centered in the optic, with the red dot on top of the front post. Lower 1/3rd co-witness places the irons in the bottom third of the optic window, allowing the red dot to float higher for a clearer view.

Why is lower 1/3rd co-witness often preferred for tactical use?

Lower 1/3rd co-witness offers a less obstructed field of view, which is crucial for situational awareness. It also provides better clearance for accessories like lasers and is more conducive to passive aiming with night vision devices.

How does optic mount height affect night vision use?

Higher optic mounts, typical of lower 1/3rd co-witness setups, provide essential clearance for night vision goggles (NVGs). This allows for easier passive aiming, where the shooter looks through the optic without activating the NVG's illuminator.

What is 'height over bore' and how does it relate to co-witnessing?

Height over bore is the distance between your optic/sights and the barrel's centerline. This difference means you must 'hold over' at very close ranges. Lower 1/3rd mounts can influence how you perceive and compensate for this effect, especially during optic failures.

Related News

All News →

More Training & Techniques Videos You Might Like

More from Regular Guy Training LLC

View all →