When you shop for 5.7×28 ammunition, the “best” choice depends on what you plan to do. Range days need affordable, consistent rounds. Defensive setups need reliable expansion. Meanwhile, varmint loads aim for fast upset on small targets. Below are the main types of 5.7x28mm ammo you will see, explained in simple terms.

• 1) FMJ (Full Metal Jacket)

FMJ 5.7×28 ammo is the common training option. It feeds well and keeps costs lower than many specialty loads. If you shoot often, FMJ is usually the bulk-buy pick for practice.

• 2) TMJ (Total Metal Jacket)

TMJ is similar to FMJ, but the jacket covers more of the base. Many shooters prefer it for cleaner indoor range use. It is also a solid bulk option for high-volume practice.

• 3) JHP (Jacketed Hollow Point)

JHP 5.7x28mm ammo is designed to expand on impact. Because of that, it is often chosen for personal defense. It costs more, but it is purpose-built for protection.

• 4) Polymer Tip (Varmint-style)

Polymer-tip loads are built for quick upset and accuracy. They can shine in small-game or varmint roles. They are also popular with shooters who want a “fast and flat” feel.

• 5) FTX / Critical Defense–style (Defense-focused tip designs)

Some defensive loads use a flexible tip design (like FTX style). These rounds aim for reliable expansion, even through light barriers. Many owners pick them for home defense setups.

• 6) Lead-Free / “LF” variants

You will also find lead-free 5.7×28 ammo. Some ranges and states prefer or require it. These loads may use different bullet construction, so confirm performance before you stock up.

• 7) “Green tip” and other tip-marked loads

Some 5.7×28 cartridges use painted tips for identification, like “green tip” references. Tip color alone is not enough to choose a load. Always match the exact product name and SKU.

Specifications of the FN 5.7×28 ammo

If you like hard numbers, here are key specs that help explain performance:

• Max Average Pressure (SAAMI MAP): 48,500 psi

• Instrumental velocity reference: 40 gr @ 1,750 fps

• Bullet diameter: .224 in (5.70 mm)

• Case length: 28.90 mm and overall length: up to 40.50 mm

• Primer type: small rifle (Boxer)

These specs support the “fast and flat” reputation, especially from longer barrels.

Design of the ammunition

The 5.7x28mm uses a rebated, bottleneck case design. That geometry supports reliable feeding in high-capacity magazines. It also helps keep recoil manageable because bullet weights are usually light.

Many common bullet styles include:

• FMJ / TMJ for training.

• Polymer tip (like V-MAX style) for rapid expansion on small targets.

• JHP defense loads that aim for controlled expansion.

What is 5.7×28 ammo used for?

Shooters buy 5.7×28 ammunition for a few clear reasons:

• Range training: low felt recoil, fast shot strings, and high capacity.

• Home defense: select a proven defensive load, and train with it.

• PDW / carbine use: Longer barrels can push velocity higher.

A practical advantage matters too. The P90 platform uses a high-capacity magazine design, and the cartridge weight is relatively low. That can reduce the carried load weight in bulk.

5.7×28 ammo vs 9mm

This comparison drives buying decisions.

5.7x28mm often gives:

• Higher velocity with lighter bullets.

• Flatter trajectory feel.

• Higher magazine capacity potential.

9mm often gives:

• Lower cost per round in many markets.

• Wider load variety across brands.

• Broad platform compatibility.

Recoil is another factor. Sources discussing the P90 system note the 5.7×28mm can produce roughly 30% less recoil than 9×19mm in that context.

If your priority is speed and control, 5.7 wins hearts quickly. If your priority is lowest cost and widest availability, 9mm usually leads.

Buy bulk 5.7×28 ammo at Smoky Mountains Guns and Ammo.

Bulk buying is not only about price. It is about consistency.

When you buy cases from SmokyMountainsGunsAndAmmo.com, you can:

• Keep one lot for training and tracking accuracy.

• Build a buffer for the match season or classes.

• Avoid “out of stock” stress when demand spikes.

Also, bulk buying lets you standardize your zero and your holds. That saves time and frustration.

Best 5.7×28 ammo 

“Best” depends on your use. Here is a practical way to choose.

For training and volume

• Federal American Eagle 5.7x28mm 40gr FMJ / TMJ is a common range pick. Federal lists 1655 fps for its 40-grain American Eagle handgun load.

For personal defense

• Speer Gold Dot 5.7x28mm is built around the Gold Dot defensive bullet design.

• Hornady Critical Defense 5.7x28mm 40gr FTX is widely chosen for defense-leaning use. It is often listed at around 1810 fps from a handgun test barrel.

For sporting / varmint-style roles

• Polymer-tip options (often V-MAX style) focus on rapid upset and an accuracy feel.

5.7×28 ammo Ballistics (in a tabular form)

Below is a published example for Hornady Critical Defense 5.7x28mm 40gr FTX (4.8″ test barrel).