I have used and tested them for about two or three months plus competed with them. We ran them over a Oehler System with two rifles showing a .466/.467 G7 at 3120 FPS. One rifle we loaded a little warmer in the 3159 FPS range, and saw a .501 G7. The test was done at 1755 yds.
Here is what I would say. Make sure you have about .187-.189” of freebore. They will shoot but seems they prefer to be seating a little into the lands. The BC sd was .033.
N570 was really good. Retumbo is another good choice. We were using a 8 twist.
Good luck and great shooting.
Chris Schmidt
JJ Rock
IG: ChrisSchmidt_ELR