6.5 Creedmoor and barrel length?

[Aberhan]

I recently purchased a Bergara B14 Stoke in 6.5 Creedmoor. This rifle comes with a 20 inch barrel. I find that although it shoots 120 grain bullets accurately enough, it really doesn’t like 140’s. Groups in this weight range are disappointing. My previous Bergara B14 HMR would handle all bullet weights extremely well, the only real difference between the two rifles is the barrel length. Plus the HMR has a heavier barrel. I’m inclined to think the 6.5 Creedmoor needs the 24 inch barrel, but what are your thoughts?

 

[Blkram]

There is no rhyme or reason as to why a barrel will, or will not, like certain bullets and/or certain bullet weights. You must try each rifle to determine which your firearm is going to prefer.
Even barrels that come of the production line in consecutive order may shoot completely different one from another, regardless that they were given the same twist, cut with the same button, and/or chambered with the same reamer. (Barrel harmonics may differ substantially due to the quality of the steel in the individual barrel blanks e.g., hardness, porosity, density, etc.)
I would imagine that both barrels have the same 1:8 twist, so hopefully that mitigates any difference in preference for bullet weight, but as mentioned above, is still no guarantee.
But as both rifles were probably manufactured in different years, there is the high probability that the cutters performing the rifling, or mandrels used for the hammer forging, were different, and/or the reamer used to chamber them were also different.
While the longer barrel is heavier, the shorter barrel, even though of a lighter profile, should be stiffer due to its length, both of which will affect the barrel harmonics as projectiles travel down the barrel, effecting bullet performance (accuracy) down range.

Have you only tried one type of bullet profile in the new rifle? E.g., High BC bullets such as the ELD-X or M, and Bergers (or vice-versa)
If so, it might be worth trying a different bullet of a different profile, such as an AccuBond or Ballistic Tip. Or even trying a flat based bullet design vs a boattail design to see if your new rifle shows promise with another profile. You may stumble onto a winner for this rifle.

And have you checked all the other variables on the new rifle?

• Bedding
• Barrel free floating, or may require a shim at the front of the barrel channel
• Action screw torqs
• Muzzle crown
• Scope and mounting system

 

[JN270]

I don't think the 6.5 Creedmoor needs a 24" Barrel. Generally speaking a longer barrel will be beneficial for velocity.

I don't think you can equate your gun not shooting a 140 grain bullet to the barrel length. I don't know what bullets you have tried. Nothing wrong with using the 120 grain. If you want to use a 140 grain try some different bullets and see.

 

[sako2]

Faster powder?