What 5.56 Ammo Does the FBI Use?

When it comes to selecting 5.56 ammo for duty use, the Federal Bureau of Investigation doesn’t gamble. Their primary 5.56 load is the 62-grain Tactical Bonded Soft Point (XM556FBIT3) from Federal Premium—a cartridge engineered for barrier penetration, controlled expansion, and reliable performance in real-world law enforcement scenarios.

Alongside their duty rounds, the FBI also issues a reduced-toxicity training load—the 50-grain Non-Toxic Jacketed Hollow Point (XM556FBITRNT50)—to allow for realistic indoor training environments without the risks associated with lead exposure.

Let’s break down each load and why the FBI relies on them.

XM556FBIT3 – The Workhorse

• Type: Tactical Bonded Soft Point
• Weight: 62 grains
• Purpose: Duty/Operational Use
• Performance Highlights:
  • Bonded construction prevents jacket-core separation.
  • Designed to penetrate barriers like auto glass and still expand reliably.
  • Delivers consistent terminal performance from both short and standard-length barrels.

XM556FBITRNT50 – The Training Round

• Type: Non-Toxic Jacketed Hollow Point
• Weight: 50 grains
• Purpose: Lead-free training
• Performance Highlights:
  • Matches duty ammo trajectory and recoil for realistic training.
  • Reduces lead exposure for agents during high-volume indoor shooting.

Together, these two loads ensure the FBI maintains a high standard of performance both in the field and on the range.

Why 62 Grains? The Sweet Spot for Duty Ammo

The FBI’s choice to run a 62-grain projectile isn’t arbitrary—it’s strategic.

62 grains strikes a balance between:

• Weight for penetration and energy retention, and
• Velocity for reliable expansion and flatter trajectory.

The bonded soft point design enhances barrier-blind performance, a must for law enforcement operating in vehicles, buildings, or urban environments.

But what if you could get the same weight class, with better expansion, deeper penetration, and solid barrier performance—out of a solid copper projectile?

That’s where the HOP Munitions 62-Grain REX comes in.

Rethinking the 62-Grain Duty Load: How HOP’s REX Elevates the Standard

We designed the 62-grain Solid Copper REX (Rapid EXpanding) round with the same mission profile as the FBI’s bonded soft point load—but we took it a step further.

This isn’t just another 62-grain round. It’s a purpose-driven evolution designed to deliver:

• Consistent expansion from short barrels like 10.5” AR pistols.
• Solid copper construction for barrier penetration without core-jacket separation.
• Enhanced terminal performance across a broader range of velocities.

62-grain 5.56 REX vs. XM556FBIT3: How They Compare

The FBI’s 62-grain XM556FBIT3 Tactical Bonded Soft Point round is purpose-built for law enforcement. It’s designed to perform through barriers while maintaining structural integrity and delivering controlled expansion. It’s a solid load—and one of the few traditional soft points trusted for duty use.

The HOP Munitions 62-grain Solid Copper REX is designed to deliver the terminal performance of a bonded soft point with the structural advantages of a monolithic solid copper projectile. The REX offers modern shooters and professionals alike a more versatile and durable option.

Side-by-Side Specifications

Federal XM556FBIT3 (FBI Duty Load)

• Manufacturer: Federal Premium
• Caliber: 5.56mm
• Bullet Weight: 62 grains
• Bullet Type: Tactical Bonded Soft Point
• Muzzle Velocity: 3,050 fps (20” test barrel)
• Casing: Brass
• Use Case: Law enforcement duty round with reliable performance through intermediate barriers.

HOP Munitions 62-grain Solid Copper REX

• Manufacturer: HOP Munitions
• Caliber: 5.56 NATO
• Bullet Weight: 62 grains
• Bullet Type: Solid Copper REX (Rapid EXpanding)
• Muzzle Velocity: 2,870 fps
• Muzzle Energy: 1,134 ft/lbs
• Ballistic Coefficient: .300
• Sectional Density: .177
• Casing: US-made brass
• Use Case: Optimized for duty use, HOG hunting, and home defense—especially in short-barreled and suppressed platforms.

Key Takeaways

• Bonded vs. Solid Copper:
  The FBI load uses a bonded jacketed lead core to prevent separation through barriers. The REX eliminates separation risk entirely by using a single-piece solid copper projectile that expands consistently, even at lower velocities.
• Velocity and Energy:
  While the FBI’s round has a slightly higher velocity (3,050 fps vs. 2,870 fps), the REX makes up for it with exceptional energy transfer and deeper, more reliable expansion from SBRs and suppressed rifles—platforms where the FBI increasingly operates.
• Barrier Blind Expansion:
  The Tactical Bonded bullet is designed for FBI protocol, but the REX was built with the Mk318 lineage in mind—delivering similar barrier-blind performance while expanding faster and more aggressively, even through intermediate materials like auto glass, drywall, and plywood.
• Accuracy and Flight Stability:
  With a ballistic coefficient of .300, the REX round flies flat and stays on target—even in wind or at extended ranges. That matches or exceeds most 5.56 soft point and OTM loads used for law enforcement and military purposes.
• Lead-Free Advantage:
  Unlike the bonded soft point, the REX is fully lead-free. That makes it ideal for both duty and training use in environments that prioritize reduced toxicity, such as indoor ranges or institutions with environmental restrictions.

Built to Surpass the Mk318:
Drawing from the proven performance of the Mk318 “Silver Bullet”, the 62-grain REX advances the formula. With tighter tolerances, faster expansion, and higher retained energy through barriers, it was engineered to outperform legacy bonded and OTM designs across duty, defense, and hunting applications.

Why the 62‑Grain REX is Designed with HRT in Mind

• Engineered for SBR Ballistics: With only 11.5″–14.5″ of barrel, muzzle velocities drop significantly—yet expansion and energy on target remain critically important. The REX’s solid copper design ensures reliability even at 2,700–2,900 fps, directly aligning with agency mission profiles.
• Barrier Performance: From auto glass and doors to structural obstacles, HRT missions frequently involve barriers. The REX reliably expands after breaching, vital for limiting over-penetration in tight environments.
• Suppressor-Friendly: Many FBI HRT rifles are suppressed. Solid copper bullets like our REX maintain performance when shot suppressed, avoiding the inconsistency often seen with barrier-sensitive bonded lead rounds.

Final Thoughts

The FBI made a smart move by choosing a 62-grain soft-point for their 5.56 duty round. It offers the right mix of weight, velocity, and barrier performance for law enforcement use.

But solid copper technology has pushed the industry forward—and the HOP Munitions 62-Grain REX leads the charge.

Whether you’re an armed professional, an armed citizen, or a serious shooter, this round is proof that duty-grade performance doesn’t stop at the federal level.