Is 6.5 better than 6.8 for hunting

[JASmith]

I think those velocities might be optimistic assuming safe pressures. The 6mm SPC (http://ammoguide.com/?catid=631) -- which will be very close to the 6 mm DTI -- shows only 2900 ft/sec with 75 grain bullets using a 20-inch barrel.

Even stretching the barrel to 24" won't likely get the added velocity with the 15 grain (20%) heavier bullet.

[stanc]

I wonder how a 6.5 SPC would stack up to a 6.5 Grendel? Had the 6.8 SPC been done as a 6.5 SPC there might have been two bulldogs in that dog pit.

For mag-length loads in an AR-15, 6.5 SPC is limited to shorter (lower BC) bullets than 6.5 Grendel.

But, if single-loaded in an AR-15, or fired in a rifle where cartridge OAL was not restricted to ~2.3 inches, 6.5 SPC would be able to use all of the long-ogive projectiles that 6.5 Grendel does, and at higher chamber pressures (producing higher MV).

[riemer]

Anyone have an energy comparison (ft lbs) between the two? I picked the Grendel because the 6.8 seems to be having some growing pains, so many variations. After my research i concluded Bill had done his due dillagance with the Grendel!

Wondering what the best pig bullet is in the 6.5?

[bwaites]

Anyone have an energy comparison (ft lbs) between the two? I picked the Grendel because the 6.8 seems to be having some growing pains, so many variations. After my research i concluded Bill had done his due dillagance with the Grendel!

Wondering what the best pig bullet is in the 6.5?

I'm not sure there is a "best" but I would look at the Barnes bullets for pigs myself.

Either the TSX/TTSX line or the TAC TX in 100 or 120 grains.

[RStewart]

Not sure if this is what you were looking for, but is some info I had found before settling on the G. As always, YMMV.

http://airbornecombatengineer.typepad.co..._vs_6.html

6.8 SPC 115gr- muzzle velocity of 2700 fps, 2417 fps at 100 meters and 1903 fps at 300 meters. Energy is 1861 at the barrel, 1492 at 100 meters, and 925 at 300 meters.

6.5 Grendel 123gr- muzzle velocity of 2600 fps, drops to 2426 fps at 100 and 2098 fps at 300. Energy starts at 1846 and drops to 1607 at 100 and 1202 at 300.

[JASmith]

...6.8 SPC 115gr- muzzle velocity of 2700 fps, 2417 fps at 100 meters and 1903 fps at 300 meters. Energy is 1861 at the barrel, 1492 at 100 meters, and 925 at 300 meters.

6.5 Grendel 123gr- muzzle velocity of 2600 fps, drops to 2426 fps at 100 and 2098 fps at 300. Energy starts at 1846 and drops to 1607 at 100 and 1202 at 300.

The 6.8 bullet with the same sectional density as the 6.5 123 gr weighs 135 grains.

Conversely, the 6.5 bullet with the same sectional density as the 115 gr 6.8 weighs just under 105 grains.

As pointed out in the quote, muzzle velocity isn't everything. I still get amused, however, by the number of folks who insist on comparing velocities with heavy Grendel bullets and light SPC bullets.

One might get suspicious that these guys are trying to bias things toward the larger caliber.

[JohnOD]

Thought I read somewhere the the .277 Barnes 95 grain TTSX the 6.8 shooters are likeing for a hunting projectile is designed to open at a lower velocity than the 6.5 100 & 120 TTSX's. Don't know this for a fact just curious if any of you knew if this was the case

[RStewart]

The 6.8 bullet with the same sectional density as the 6.5 123 gr weighs 135 grains.

Conversely, the 6.5 bullet with the same sectional density as the 115 gr 6.8 weighs just under 105 grains.

As pointed out in the quote, muzzle velocity isn't everything. I still get amused, however, by the number of folks who insist on comparing velocities with heavy Grendel bullets and light SPC bullets.

One might get suspicious that these guys are trying to bias things toward the larger caliber.

The data was more for the energy info, since that was what the OP's original question had been. Muzzle velocity was already a part of the report.
I think he was looking for it in relation to knockdown power on hogs. And yes, a 123gr bullet traveling at 2600 fps muzzle versus a 115gr bullet traveling at 2700 fps muzzle is probably not a necessarily fair comparison. But for knockdown, I'll personally take a 123 or bigger over a 115. Otherwise, I'll just use my AR with 80's.

[riemer]

Thanks for the information! Still proves that I made the right choice! I am/was a velocity freak, faster the better, but when you look at how fast these rounds scrub velocity, the retained energy remains very attractive.