Range results:
Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)
.25x40mm 16" 1:10 carbine length gas system, fire-formed brass...worked up several loads between but only posted the whole and half unit loads....
85gr Nosler BT, 21.5gr 1680 = 2,757 fps
85gr Nosler BT, 22gr 1680 = 2,810 fps
85gr Nosler BT, 22.5gr 1680 = 2,853 fps
85gr Nosler BT, 23gr 1680 = 2,913 fps
Averages of 20 rd. strings......
the 1680 produced very linear velocity results with the 85s.......very good velocity per grain of powder......
I tried about eight different powders with the 85 and 100 grainers today.....the only thing that even came close to the performance of the 1680 was 5744 but ran out of room at 21.5grains and was still 150fps slower....
Kurtz