First, I don't think the CM will be off 1.4 gr. I have a friend who uses one that is much more repeatable than that.
Second, I will always trust my target over my chronograph. Personally, I primarily use my chronograph to watch muzzle velocity as a means of watching for excess pressure. By the time you are seeing pressure signs on your brass you are already in dangerous territory.
Third, if you pay attention to your target and find a good node then minor variations in charge weight won't affect you appreciably. I recently ran a test with my 600 yd F-Class load. I loaded 2 rounds each at my charge weight and 0.1gr above and below my charge weight. I shot these at 287 yds, the longest range available locally. I shot a 0.45 moa group with these 6 rounds at 287 yds. I had one shot that I knew I pulled and was out of the group but was included in the 0.45 moa. Without that shot, it would have been 0.2 moa.
FWIW, I subscribe to Dan Newberry's OCW method. It has worked well for me for quite a few years.
Second, I will always trust my target over my chronograph. Personally, I primarily use my chronograph to watch muzzle velocity as a means of watching for excess pressure. By the time you are seeing pressure signs on your brass you are already in dangerous territory.
Third, if you pay attention to your target and find a good node then minor variations in charge weight won't affect you appreciably. I recently ran a test with my 600 yd F-Class load. I loaded 2 rounds each at my charge weight and 0.1gr above and below my charge weight. I shot these at 287 yds, the longest range available locally. I shot a 0.45 moa group with these 6 rounds at 287 yds. I had one shot that I knew I pulled and was out of the group but was included in the 0.45 moa. Without that shot, it would have been 0.2 moa.
FWIW, I subscribe to Dan Newberry's OCW method. It has worked well for me for quite a few years.









