Given the choice for sub 800

[maltbuck]

As per title given the choice, what would you choose a 6mm using 105-108 grain, or a 6.5mm using 123-130 grain?

 

Regards, MB.

[1967spud]

6.5

[That bald headed Geordie]

I have just checked the difference in a 10mph wind at 90 deg between using a 6.5x55Ack Imp and a 6BR at the velocities I use, and the windage needed for the 6.5 is 4.4 moa and 6 moa for the 6BR. So as my wind reading skills are not great I would use the 6.5 in windy conditions. But I love my 6BR and on more benign days I am sure that it will more than hold its own.

[gbal]

As per title given the choice, what would you choose a 6mm using 105-108 grain, or a 6.5mm using 123-130 grain?

Regards, MB.

Not much in it to about 5/600 y,then the advantage 'drifts' to the 6.5,and more so as wind increases.The 6.5 will need to be about 2+ lb heavier to equate recoil,and it will have longer barrel life,and may transfer more effective energy into sentient targets-though this is more a bullet construction issue.

 

115 g 243 Dtacs for the 6mm would reduce the gap,but then again 142g 6.5s would just open it up again. (115 and 142 are 'optimum weights' for the two ,with very similar BCs,around .57. Not cheapest etc,'ballistically optimum'.Such parity means MV around 3000,viz: 3065 for 6mm,and 2950 for 6.5. Any disagreements,send your mathematical proofs to Brian Litz,c/o Berger bullets).

 

Gbal

[John MH]

Out to 800 yards not much between a 6mm or 6.5mm, the 6mm might be more comfortable to shoot but the 6.5mm is not a bruiser. Personally I'd go with the 6mm but I'm using a 6XC, in 6.5mm I tend to use 139 grains bullets.

[Chris-NZ]

As George and John have said, much of a muchness with those projectile weights and a similar boiler room.

 

My 6.5x47 runs 123s and I'm just about to try the new 6x47 as the scope arrived yesterday. I'll be feeding it 105 Hybrids which are as good as the DTACs for slipperiness but far more forgiving on seating depth. Assuming a 3150MV, the 105 Hybrids will easily beat the 123 6.5s in the wind. You'd need to up the ante with a bigger 6.5 case to get ahead of this 6mm combo.

[maltbuck]

Thanks for the replies. Did not think there was much in it, particularly when considering 6.5's that have less powder capacity than the 260 or 6.5x284.

Will take a harder look at the berger 105 hybrid option for a 6mmXC or 6-6x47.

 

Thank you once again.

[walkabout]

What ever you go for, a consideration is availability of components if you intend to do a lot of shooting?

105 Berger Hybrids are fantastic...if you can get them!

I have tried 4 different suppliers and non in stock and not expecting them anytime.

Mik at Dolphin has a big order from Berger on back order but no 105's in that order.

115 DTACS I have managed to getand to shoot through my 8 twist 6x47 Lapua but they are hard to get aswell.

At least with the 6.5x47 Lap 123gn & 139gn Lapua bullets are available most of the time.

Something to think about, but supplies may change next year?

[Scotch_egg]

115 DTACS I have managed to getand to shoot through my 8 twist 6x47

Sorry to go off subject but what barrel are you using to stabilise the 115's in a 1-8" twist?

[walkabout]

It's a Bartlein 28" 1-8 twist 5r cut

I have read that a true 8 twist will do it, but it needs to be a cut barrel, button pulled may not be a true 1-8 twist

 

Mark