6.5 Creedmore max load

[WildRose]

Not hurting feelings at all. Just wanted the 30 inch for F Class soon, and you can always set back later in case your chamber is shot up. I'll keep an eye out for high pressure signs, but will stick under max or right at max. Hopefully it should gain velocity before I get to max. Speed is not what I am looking for, just asking about what you guys are using. I am just looking for accuracy. Thanks for the input.

That's the value of the extra length. Sometimes you just find a barrel that shoots really well and if you can have the same gunsmith set it back and rechamber it for you, odds are it will continue shooting well for you even after a couple of set backs.

 

[Wind Gypsy]

I don't buy that a 6.5 creed won't pick up speed by adding barrel length beyond 24-26"..

 

[gohring3006]

I don't buy that a 6.5 creed won't pick up speed by adding barrel length beyond 24-26"..

There is a good chance you might gain some speed.
And there is a good chance you will lose some as well. Depends on the barrel.
The tests revealed, there is no guarantee you will gain velocity with small case capacity cartridges and long barrels....

 

[WildRose]

There is a good chance you might gain some speed.
And there is a good chance you will lose some as well. Depends on the barrel.
The tests revealed, there is no guarantee you will gain velocity with small case capacity cartridges and long barrels....

Yep, it's all about case capacity and the powder.

Theoretically longer barrels combined with slower burning powders will produce more velocity and do so at lower pressures than faster burning powders.

There is however a point of diminishing returns with everything and no matter what powder you are using there's only so much of it because of the space available in the case.

 

[Wind Gypsy]

6br barrels have proven to gain velocity up to and past 30". 308 competition barrels are not uncommon up to and past 30". That comes at a harmonics penalty and they wouldn't do it if they didn't gain velocity. 6.5 creedmoor has a higher case capacity to bore size ratio than both of these cartridges.

Where is there evidence of diminishing speeds past 24 or 26"?
I'd be interested to see a barrel cut down compare like the 6br and 308 ones shown here. .308 Win Barrel Cut-Down Test: Velocity vs. Barrel Length « Daily Bulletin

 

[gohring3006]

For some reason I can't share any links on this phone.
But Google Rifleshooter.com 6.5 Creedmoor, the author went from 27" down to 22" and you will see he gained a little velocity at I believe the 24" mark. And you will see he hardly lost any significant velocity going from 27" to 22"... Not enough in my opinion to have a front heavy unbalanced rifle...

 

[WildRose]

6br barrels have proven to gain velocity up to and past 30". 308 competition barrels are not uncommon up to and past 30". That comes at a harmonics penalty and they wouldn't do it if they didn't gain velocity. 6.5 creedmoor has a higher case capacity to bore size ratio than both of these cartridges.

Where is there evidence of diminishing speeds past 24 or 26"?
I'd be interested to see a barrel cut down compare like the 6br and 308 ones shown here. .308 Win Barrel Cut-Down Test: Velocity vs. Barrel Length « Daily Bulletin

308 win has 55-57gr capacity depending on mfg and the 6.5CM around 52.

As for barrel length there is a small gain in going with a long barrel with the 6mm BR at least in some cases.

How Much More Velocity Will I Get with a Longer Barrel? Going from 20" to 24" can increase velocities up to 160fps (40fps per added inch), depending on the rifling. After that, expect another 25-30fps extra velocity for each added inch up to about 28". Beyond that, you'll probably get a little extra speed, especially with 6BR Improved cases. We recently completed a barrel velocity test using a rail-gun. A Krieger 6mm barrel chambered for a standard 6BR was cut down from 33" to 28" in one-inch increments. The Average Velocity at 33" was 40 fps higher than at 28". The Average Velocities showed a pretty steady increase of 8 fps per inch past 28". For example the Average Velocity at 30" was 16 fps higher than at 28". Based on this study, you're not going to gain much by going from 28" to 30". And world-record-holder Richard Schatz is getting 3025fps with his 6 Dasher using a 26" Hart barrel. So arguably, 26" is long enough, at least for the Improved cases. For maximum speed, 30" is a useful limit, but remember that this adds weight to the gun and you'll be sacrificing barrel stiffness.

Barrel FAQ -- Barrel Velocities, Lengths, Twist Rate, Contours, Cleaning, Accuracy and Ballistics for Benchrest, Hunting, Precision Shooting

Build what you want, no one here is going to tell you otherwise but the fact remains there's a point of diminishing returns because there's only so much powder to burn.

 

[WildRose]

For some reason I can't share any links on this phone.
But Google Rifleshooter.com 6.5 Creedmoor, the author went from 27" down to 22" and you will see he gained a little velocity at I believe the 24" mark. And you will see he hardly lost any significant velocity going from 27" to 22"... Not enough in my opinion to have a front heavy unbalanced rifle...

I think this is the article you're talking about.


6.5 Creedmoor- Effect of Barrel Length on Velocity: Cutting up a Creedmoor! | Rifleshooter.com

Good data.

 

[gohring3006]

I think this is the article you're talking about.


6.5 Creedmoor- Effect of Barrel Length on Velocity: Cutting up a Creedmoor! | Rifleshooter.com

Good data.

That's it.... I spent ten minutes trying to share it on here, and gave up.... Thanks for sharing..

 

[TackDriv3r]

I think this is the article you're talking about.


6.5 Creedmoor- Effect of Barrel Length on Velocity: Cutting up a Creedmoor! | Rifleshooter.com

Good data.

Wow, its a good read, the suspense was killing me. Seemed that the speed of the 142 gr dropped fast after 24 inches of barrel compared to the lighter bullets. I'll experiment with some loads and using the ladder test / chrono and hopefully find some good groups. Thanks guys for the good info.

 

[Wachsmann]

I have a friend at work that must have a really fast barrel. It a 26 inch creed and he getting 2860 out of his with 140. I don't know if they were Amax's or bergers. He would tease me because my 6.5x284 seem to be slower than most until I starting burning retumbo..... Now it runs at 2940ish.

 

[Wind Gypsy]

Thanks for sharing that article. From the article:

The decrease may be related to the barrel length, however, it may also be related to the fact the barrel was new and may have needed more fouling prior to the test.

I would put good $ on it that if the same test was performed on a barrel that had stabilized after a few hundred "break in" rounds you would see consistent gains in velocity with additional barrel length up to 30".

I agree with many points made about velocity vs handiness, but it's misguided to choose shorter 6.5 creed barrels because "they lose velocity after 24".

 

[North Idaho Hunter]

Just worked up a load with a friend in his 6.5 creed in a 27 inch benchmark. he's getting 2768 FPS validated with 140 bergers. Very nice shooting rifle!

 

[TackDriv3r]

Went to the range to do the ladder test, but ran out of VLD 140's, so there are 3 tests for the 140 VLD and 5 tests for the 130 VLD, all full sized and new brass. The 140 VLD did one nice 3 in 1 hole but the 4th was a flyer, not sure why. I see some promise with two loads of 130 VLD's with 4 in one hole and another with 3 in one hole and one just above it but has high ES. Speed was around 2930 fps on last test of 130 VLD and 2750 fps with 140 VLD. None of the loads showed any high pressure. Powder charge is not max,,,yet. Opinions and what shall I look for next?