So here are my last two results with the 198 Flatlines and N570.
The target with 6 different groups (5 are from the .300 NM, the one on the very bottom left is from one of my 7 WSMs) is the most recent and was testing seating depths. All my previous shooting was done with the projectiles touching the lands. The rifle/projectiles seem to prefer .005 jump better for accuracy than touching and definitely didn't seem to like jumping .020 or .050 jump. This wasn't much of a surprise since they are so long. These groups were shot at 100 yards and the best was the CCB with .005 jump and measured 2/3 MOA.
No, they aren't 5-shot groups with the cost to shoot these things, plus barrel life; I'm not keen on wasting them.
The other target with one group was shot at 300 yards. It was 6x 3-shot groups with varying powder charges, and the projos were set to touching. It managed about 1.1 MOA.
I only have about 70 rounds through this barrel but 1 MOA seems to be about where I'm at with it or a little better. I'm also not pushing these projectiles as fast as I could but I'm not trying to kill the brass within 2 firings either.
By the way, I have an unopened 8-pound jug of Retumbo if anyone has some N570 to trade around Texas.
The target with 6 different groups (5 are from the .300 NM, the one on the very bottom left is from one of my 7 WSMs) is the most recent and was testing seating depths. All my previous shooting was done with the projectiles touching the lands. The rifle/projectiles seem to prefer .005 jump better for accuracy than touching and definitely didn't seem to like jumping .020 or .050 jump. This wasn't much of a surprise since they are so long. These groups were shot at 100 yards and the best was the CCB with .005 jump and measured 2/3 MOA.
No, they aren't 5-shot groups with the cost to shoot these things, plus barrel life; I'm not keen on wasting them.
The other target with one group was shot at 300 yards. It was 6x 3-shot groups with varying powder charges, and the projos were set to touching. It managed about 1.1 MOA.
I only have about 70 rounds through this barrel but 1 MOA seems to be about where I'm at with it or a little better. I'm also not pushing these projectiles as fast as I could but I'm not trying to kill the brass within 2 firings either.
By the way, I have an unopened 8-pound jug of Retumbo if anyone has some N570 to trade around Texas.
