This is not a comprehensive search but there were velocities posted in the 12” group buy and the 12.7” group buy threads. I also posted some results from David Fortier from several years ago.
Chronograph 12”, 12.5”, 12.7” 6.5 Grendel results
http://www.65grendel.com/forum/showthrea...p-H/page32
http://www.65grendel.com/forum/showthrea...-Buy/page7
Alexander Arms 20 inch GDMR
6.5mm Grendel Muzzle Velocity (fps)
Alexander Arms 100 grain Berger OTM 2,847
Alexander Arms 120 grain Barnes TSX 2,551
Alexander Arms 120 grain Nosler BT 2,600
Wolf 120 grain MPT 2,541
Alexander Arms 123 grain Lapua Scenar 2,627
Hornady 123 grain A-MAX 2,582
Alexander Arms 129 grain Hornady SST 2,450
Alexander Arms 130 grain Swift Scirocco II 2,400
Alexander Arms 16 inch Mid-Length carbine
6.5mm Grendel Muzzle Velocity (fps)
Alexander Arms 100 grain Berger OTM 2,723
Alexander Arms 120 grain Barnes TSX 2,494
Alexander Arms 120 grain Nosler BT 2,535
Wolf 120 grain MPT 2,445
Alexander Arms 123 grain Lapua Scenar 2,523
Hornady 123 grain A-MAX 2,463
Velocities are averages of five shots measured on an Oehler 35P chronograph 12 feet from the muzzle at an ambient temperature of 90 degrees F at 1030 feet above Sea Level.
Alexander Arms 12.5 inch 6.5mm Grendel
Alexander Arms 100 grain Berger OTM 2470
Alexander Arms 123 grain Scenar OTM 2330
Velocity figures are 10 shot averages recorded on an Oehler 35P placed 12 feet from the muzzle 1,030 feet above Sea Level at an ambient temperature of 30 degrees F.
*Note the low temps with the 12.5 inch gun
From the first link here 12” chronograph results.
Wolf 100 Grain, 10 shot average: 2361.5 GPS
123 Grain Amax 27.8 gr 8208 XBR, 10 shot average: 2275.5
This load averages 2420 FPS in my 18 inch Odin barrel.
Elevation: 300 ft
90 degrees F
Here is a link to 12.5” with suppressor from post on AR-15.com.
https://www.ar15.com/forums/AR-15/Suppre...16-728810/