.408 CheyTac?

Ok, could add some more:

The match ammo I'm comparing against(I.e the ones I occasionally use)
is:

Lapua Lockbase
Lapua FMJBT
Federal Gold Match(Might just be me, but I was kinda disappointed. I don't know, but I just didn't feel comfortable with it)
Handloaded(waste of time for me, didn't have any noticeable effect, not better, not worse. Besides, I can't get hold of the propellant Lapua, Raufoss and Vanäsverken/FMV uses)

Mel:

If you ever find Lapua Lockbase or FMJBT in a store and have spare cash, I'd recommend at least testing either of them. I like them a lot

Mel:

Yes, the current breed is indeed better.
Lower velocity, around 1260m/s but heavier(6.2g), with the same diameter, so retardation is even lower. Lots of kinetic energy too.
Most of the 1 million rounds ordered from Winchester in 1998 are placed in various weapon caches and mobilization storage.

V0 and Energy are at muzzle, any other distances would depend on external factors too.
Diameter of projectile is 4.81mm
Area of cross-section: Roughly 18.17 mm²

Original Winchester SLAP:
V0=1340m/s
Mass=3.4g
Energy=3052.52 joule
Energy/mm²=168 joule rounded up

7.62x51 Sk PTR10 Prick(T)
V0=1260m/s
Mass=6.2g
Energy=4921,56 joule
Energy/mm²=271 joule rounded up

As a contrast, here's the stats for the 7.62x51 SK Ptr10 PPrj (Swedish AP ammo)
Area of cross-section: 45.6mm²

V0=960m/s
Mass=8.2g
Energy=3778.56 joule
Energy/mm²=82.9 joule

Here's the Lapua .338 Magnum FMJBT Lock-base
Area of cross-section: 58.1mm²

V0=915m/s
Mass=16.2g
Energy=6781.5 joule
Energy/mm²=117 joule rounded up

On the other hand, the .338 Lapua Magnum has higher momentum than the other mentioned rounds, and a high weight compared to the bullet diameter, so its retardation is low too.

OK, I've had a chance to read up on some Swedish forums, and a person in Finland commented about the .408 CheyTac. He's had an opportunity to testfire it, and his comment was that there's a lot of hype surrounding it. It's not bad, according to him, but it doesn't outperform the .50BMG, and it packs a hell of a lot more recoil than the .338 Lapua Magnum, so it wasn't really better. He also pointed out that the ballistics test that they have published involves their own precision bullet for the .408 while they tested against ordinary 12.7x99 M33 Ball. He did his own comparison with his handloaded 12.7x99, with 50g(773gr) bullets of Warren Jensen's, i.e Lost River's, own manufacture(The same company that makes the bullets for the .408 Cheyenne, btw...), and it outperformed the .408 Cheyenne in every aspect, and reaches a BC of 1-1.1 according to testing. He also commented about the .338 Lapua Magnum. In the comparison with the .338 Lapua Magnum, they used a 16.2g(250gr) Scenar bullet, when there are better bullets with higher BC's available, such as the 19.44g(300gr) Sierra Matchking available. He's personally reached 0.8BC.

So, it's pretty interesting when the company doesn't even dare to compare their .408 to their own 12.7x99 ammo.