6.5 mm (.257) Airgun Ammunition

6.5 mm (.257) Airgun Ammunition: Maximum Performance for High-Power PCP Air Rifles

6.5 mm (.257) is a specialised calibre developed for powerful PCP air rifles. Thanks to its larger projectile diameter and increased projectile weight, this calibre delivers outstanding performance at medium and long shooting distances. Combined with modern PCP platforms, the .257 offers an excellent balance of power, accuracy and ballistic efficiency.

At SEM Jacht & Schietsport you'll find a carefully selected range of 6.5 mm (.257) airgun ammunition. This category is intended for shooters who demand maximum performance from their PCP air rifle and are looking for premium slugs and precision-manufactured projectiles.

Why choose 6.5 mm (.257)?

The .257 calibre bridges the gap between the popular .25 and .30 calibres. The heavier projectile delivers more energy than .25 while maintaining excellent stability and retained velocity over longer distances, making it an outstanding choice for high-powered PCP air rifles.

• More energy than 6.35 mm (.25).
• Excellent stability at medium and long range.
• Designed for powerful PCP air rifles.
• Available in a variety of slug weights.
• Ideal for shooters demanding maximum precision.

Which air rifles are available in 6.5 mm (.257)?

Although .257 is considered a niche calibre, several manufacturers have developed PCP air rifles specifically for this cartridge.

• AirForce Texan .257
• Benjamin Bulldog M257
• Western Airguns Sidewinder .257
• Various custom-built PCP air rifles chambered in .257.

These rifles are engineered to stabilise heavier projectiles efficiently, allowing shooters to take full advantage of the calibre's ballistic characteristics.

Slugs are the standard for .257

Unlike smaller airgun calibres, the vast majority of 6.5 mm (.257) ammunition consists of slugs. Their higher ballistic coefficient (BC) allows them to retain velocity more effectively while reducing wind drift over longer distances.

For optimum performance, the slug weight, barrel twist rate and rifle power should always be properly matched.

Projectile weight, BC and long-range performance

Projectile weight is measured in grains (gr). Compared to smaller calibres, .257 projectiles offer higher sectional density (SD) and frequently a higher ballistic coefficient, resulting in excellent long-range performance.

Common projectile weights include:

• 34 to 40 grains.
• 40 to 50 grains.
• 50 to 60 grains.
• Heavier slugs for specialised applications.

The combination of increased weight, higher BC and excellent retained velocity makes .257 slugs exceptionally stable at extended distances. Many experienced PCP shooters test multiple projectile weights to determine the most accurate load for their rifle.

Leading 6.5 mm (.257) ammunition brands

SEM Jacht & Schietsport supplies premium .257 ammunition from respected specialist manufacturers.

• Nielsen Specialty Ammo
• ZAN Projectiles
• Air Venturi
• Rifle

These manufacturers are recognised for precision manufacturing, consistent quality and outstanding performance in high-powered PCP air rifles.

Frequently Asked Questions

Is 6.5 mm the same as .257 calibre?

Yes. 6.5 mm and .257 are simply two different designations for the same calibre.

Is .257 ammunition mainly available as slugs?

Yes. Most commercially available .257 airgun ammunition consists of slugs specifically designed for high-powered PCP air rifles.

Why is ballistic coefficient (BC) important?

A higher ballistic coefficient helps the projectile retain velocity more effectively while reducing wind drift, improving long-range accuracy.

Can every PCP air rifle shoot .257 slugs?

No. Only air rifles specifically chambered for .257 calibre should be used with this ammunition.

Why do experienced shooters choose .257?

The calibre offers an excellent combination of power, retained energy, stability and long-range accuracy, making it a popular choice among serious PCP shooters.

Why choose SEM Jacht & Schietsport?

SEM Jacht & Schietsport offers a carefully selected range of 6.5 mm (.257) airgun ammunition for high-performance PCP air rifles. With extensive knowledge of PCP systems, projectile weights and external ballistics, we're happy to help you select the ideal ammunition to achieve the highest level of accuracy and performance.