Gun Gripes #345: "Are 7.5 Inch ARs Useless?"

Published on January 3, 2023
Duration: 22:53

This video critically examines the utility of 7.5-inch AR-15 barrels, concluding they are impractical for serious use due to significantly reduced 5.56mm velocity and terminal performance. While offering a 'fun factor' for range use, they suffer from reliability issues and are outperformed by calibers like .300 Blackout in short configurations. The speakers recommend at least 11.5-inch barrels for practical applications.

Quick Summary

7.5-inch AR-15 barrels in 5.56 NATO significantly reduce velocity to around 2100-2200 FPS, compromising terminal ballistics. Effective performance typically requires over 2600 FPS for fragmentation. Specialized ammo can help, but calibers like .300 Blackout are better suited for short platforms.

Chapters

  1. 00:00Introduction & Sponsor: 7.5" ARs
  2. 01:09Barrel Length vs. Velocity
  3. 02:11Terminal Performance Thresholds (5.56mm)
  4. 03:58Comparing Short Barrels (7" vs 10.3" vs 11.5")
  5. 05:58Specialized Ammo for Short Barrels
  6. 10:41Gas System & Reliability Issues
  7. 13:41Fun Factor vs. Practical Utility
  8. 15:31Better Short Barrel Caliber Alternatives

Frequently Asked Questions

What is the main drawback of a 7.5-inch AR-15 barrel in 5.56 NATO?

The primary drawback is significantly reduced velocity, often around 2100-2200 FPS. This compromises terminal ballistics, making the round less effective for tumbling or fragmentation, similar to a heavy .22 Magnum.

What velocity is needed for 5.56 NATO to perform effectively?

For standard 5.56 NATO rounds like M193 or M855, a velocity above 2600 FPS is generally considered necessary to ensure reliable bullet tumbling or fragmentation for effective terminal performance.

Are there specialized ammunition options for short-barreled 5.56 ARs?

Yes, heavy projectiles (77gr, 75gr) or bonded bullets (like Gold Dot or Federal Trophy Bonded) are designed to expand at lower velocities, typically down to around 1800 FPS, mitigating some performance loss.

What are the reliability concerns with very short AR-15 barrels?

Short barrels, especially with pistol-length gas systems, create extremely high port pressures leading to violent cycling, increased wear on components, and significant reliability challenges compared to longer systems.

Related News

All News →

More Reviews Videos You Might Like

More from Iraqveteran8888

View all →