Second round of testing
- Thread starter welderboy
- Start date
4-5-6-7 have the least vertical spread between them, indicating minimal increase in muzzle velocity. Your chrony numbers support this, with 5 and 6 being the closest. This is the "node" where increasing the powder charge causes the smallest increase in muzzle velocity.
I would do another ladder, going from 99.5 to 101 in smaller 0.3gr increments. This will let you narrow down the exact range of powder for the node. If you can do it at a longer distance, the better, 300yds is really the absolute minimum for a ladder test.
Then pick the best charge from it and shoot a few groups to confirm the spread in muzzle velocity.
You can also then try to fine-tune the group size by tweaking with the OAL of the rounds, but I have had very consistent success using the method above.
Lastly, I pick the charge at the bottom of the node when doing the tests in cold weather, that way when in warmer weather, the increase in velocity from the higher temperatures won't push me out of the node.
I would do another ladder, going from 99.5 to 101 in smaller 0.3gr increments. This will let you narrow down the exact range of powder for the node. If you can do it at a longer distance, the better, 300yds is really the absolute minimum for a ladder test.
Then pick the best charge from it and shoot a few groups to confirm the spread in muzzle velocity.
You can also then try to fine-tune the group size by tweaking with the OAL of the rounds, but I have had very consistent success using the method above.
Lastly, I pick the charge at the bottom of the node when doing the tests in cold weather, that way when in warmer weather, the increase in velocity from the higher temperatures won't push me out of the node.
