Ballistic comparisons

[XcountryRider]

I ran the numbers for a couple different grains of bullets to compare to the 6.8SPC 120SST. What this shows me is that the standard conventional wisdom about the 6.8SPC being better for close in shots while the Grendel is a better long distance killer is just internet lore. In fact when looking at 120gr to 123gr hunting rounds the Grendel is more effective right from the barrel. This shows in the Hornady HITS scores.

[babaganoush]

From:

http://www.quarry.nildram.co.uk/Assault.htm

Considering the 6,8 SPC as a potential military cartridge, the author goes on to say:

I don't know how the 6.8 SPC crowd continues to naysay the 6.5 Grendel. As far as a battle cartridge goes, both face similar hurdles, but I am not even remotely qualified to discuss that, and there have been several threads in the last few months that have gone into excruciating detail on the subject.

[stanc]

More recently, another challenger emerged in the form of the 6.5mm Grendel (6.5x38).This uses a slightly fatter case (the same 11.3mm diameter as the 7.62x39 Russian) which enables it to be shorter, thereby leaving space for longer and more aerodynamic bullets. This enables it to fire a 123 grain Lapua Scenar bullet at 2,530 fps (8.0g at 770 m/s: 2,370J) from a 16 inch barrel...

In a...MG barrel this provides trajectory and velocity loss figures to match or better those of the 7.62x51 M80 ball round.

INVALID COMPARISON!!! Lapua Scenars are not fired in machine guns, FMJ projectiles are. Since a 6.5mm FMJ bullet would have a BC significantly lower than that of the 123gr Scenar, the quoted performance claim is misleading, at best.

[bwaites]

INVALID COMPARISON!!! Lapua Scenars are not fired in machine guns, FMJ projectiles are. Since a 6.5mm FMJ bullet would have a BC significantly lower than that of the 123gr Scenar, the quoted performance claim is misleading, at best.

Actually, you can't be sure it would have a lower BC. There is no reason for it to do so, since design and manufacture has significantly improved. There is no reason to not have a similar BC. You are assuming that some current bullet would be used, which is not probably the case at all. It would be a bullet designed specifically for the use. Your assumption is at least as much in error as his.

[XcountryRider]

Look at the 100 yard mark the Grendel already has a 100 point lead in HITS.

http://www.hornady.com/hits/calculator

[babaganoush]

As I said, I'm not qualified to discuss what an appropriate battle cartridge would be. But I believe the larger point is being overlooked here. The OP was striving to draw a comparison between the 6.8 SPC and the 6.5 Grendel's ballistic performance.

The article cited, despite the aforementioned erroneous assumption with respect to a the selection for a combat round, still seems to support the OP's contention that the 6.8 SPC has virtually no high ground, compared to the 6.5 Grendel.

David

[stanc]

Actually, you can't be sure it would have a lower BC. There is no reason for it to do so, since design and manufacture has significantly improved. There is no reason to not have a similar BC. You are assuming that some current bullet would be used, which is not probably the case at all. It would be a bullet designed specifically for the use. Your assumption is at least as much in error as his.

You may be right, Bill. That's one reason I look forward to the Wolf steel case load. If its FMJ is similar in shape to the Russki 5.45mm Ball projectile, it should be more indicative of how good the BC can be made.