I calculate three times the speed of sound as 3,350 fps which surprised me. I would have guessed it to be much higher. Three times the speed of sound sounds a lot more impressive to me than 3350 fps.
Crack of the whip.
I don’t think the .338 Lapua can shove even anything heavier than a 200gr pill out at 3,200+ fps. My .338 WM with a 210gr pill is about 2850 to 2900, depending on how hot I load it, and the extra powder for the Lapua wouldn’t add more than about 300fps to that.
I’d guess they’re using the heavy HPBT match scenar bullets (they’ve got some awesome BC’s) and launching in the 2850-2950 fps range for a 250gr, 2650 to 2750fps for a 300gr.
There are some simply wonderful long-range, VLD pills in the 300gr range for the .338. The Lapua Scenar 300gr holds a BC > 0.740 while supersonic, and > 0.780 at muzzle velocities. If you’re looking for high-BC pills, you’re hard pressed to beat the .338 until you get into the .408’s recently designed here, or some of the very long 6.5mm’s (.260cal).