Bartlein Barrel - SS, 6mm, B# 1.250" Straight, 8 twist, 29'' blank, 5R

The Bartlein Barrel - SS in 6mm caliber with a B# 1.250" Straight contour, 8 twist rate, and 29'' blank length is a precision-engineered firearm component that can significantly impact your shooting experience. In this comprehensive guide, we will explore various aspects of barrel performance and design.

Do Contours Affect Barrel Weight and Performance?

Yes, the contour of a barrel can have a noticeable effect on its weight and performance. Heavier contours tend to perform better than lighter ones, especially when the barrel is subjected to heat during continuous shooting. A heavier barrel resists movement and wandering as it heats up, contributing to better accuracy.

At Bartlein Barrels, we exclusively utilize single point cut rifling, which eliminates stress in the barrel blank. This means that for barrels created through single point cut rifling, the contour is not as critical as it would be for barrels made with other methods like button rifling.

How Does Contour Affect Shooting?

Contour does affect shooting performance. Heavier barrels offer advantages, as the additional weight helps shooters manage recoil, leading to reduced fatigue and improved accuracy. Shooters can fire more rounds over extended periods with greater ease when using a heavier gun.

However, it's worth noting that lighter weight contours can still deliver excellent performance, sometimes even outperforming heavier ones. While important, contour is not the sole determinant of shooting success.

Should Suppressors Be Used with Any Barrel Contour?

No, suppressors should not be indiscriminately mounted on any barrel contour. Suppressors tend to perform better when attached to heavier barrels because their weight affects the harmonic vibrations of the barrel. For optimal results with suppressors, it's advisable to avoid mounting them on barrels smaller than a medium palma contour.

Advantages of Single Point Cut Rifling Over Button Rifling

Single point cut rifling, the preferred method at Bartlein Barrels, offers several advantages over button rifling. In button rifling, lighter weight contours can introduce substantial stress into the barrel blank. As contours become smaller, bore sizes can change and open up, limiting the ability to reduce bore size. This issue is absent in single point cut rifling, ensuring consistent bore dimensions and accuracy.

Threaded muzzle ends for muzzle brakes or suppressor attachments are prone to bore opening in button rifled barrels, especially at the critical muzzle crown edge. Any compromise in this area can negatively impact accuracy, making single point cut rifling a more reliable choice.

Significance of Fluting a Barrel

Fluting a barrel serves multiple purposes:

• Weight Reduction: By removing material without altering the contour, fluting reduces barrel weight.
• Barrel Cooling: Fluting increases surface area, promoting better heat dissipation during prolonged shooting sessions.
• Aesthetic Appeal: Many shooters appreciate the unique appearance that fluting adds to a barrel.

FAQs About Fluting

Minimum Depth: Excessive fluting depth can lead to harmonic and vibration issues, potentially affecting accuracy. If you cannot add fluting while selecting a barrel, the contour may be too shallow.

Impact on Barrel Stiffness: Fluted barrels are generally less stiff compared to non-fluted ones. Stiffness measurement depends on factors like contour and design.

Importance of Rifling Style

The rifling style on a barrel is crucial for accuracy and bullet performance. Bartlein Barrels offers three rifling types: 4-groove, 5R, and Conventional-5. The number of grooves does not significantly affect accuracy or barrel life, as validated by ammunition and bullet manufacturers.

Additional Benefits of 5R Rifling

5R rifling provides advantages, including reduced bullet failure due to its gentler lands' angle. The design features 5 lands in the barrel bore, preventing direct opposition between lands. This deformation results in less distortion to bullet jackets when transitioning from the case to the rifling, enhancing bullet stability and accuracy.

We've also discovered that 5R rifling positively impacts bullet flight, based on insights from ammunition and bullet makers.

Exceptions:

Short Jacket 6mm Bullets: Short-range bench shooters using 65-68gr bullets may not favor the 5R style of rifling. Accuracy with these bullets may be compromised, particularly with boat tail bullet designs. The short bearing surface area of these bullets combined with the "R" style of rifling can lead to insufficient bullet grip.