Nature Boy
Member
- Joined
- Apr 21, 2015
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- 8,254
I’ve been curious how load development performed at 100 yards would stack up compared to the traditional ladder test shot at distance. Time and weather finally allowed me a window to get it done this morning.
Bottom line: both methods compared favorably to each other.
First, here’s the hundred yard load test a did a few weeks ago. This is my preferred method.
You load 3 rounds each at increasing charge weights and shoot them in order (not round robin). To find the accuracy nodes you look for group centers that deviate the least from point of aim when compared to adjacent groups. Also, flat spots in FPS data should correlate to the node. My notes on the target indicate avg FPS on the left, charge weight on top, group center distance to POA on right and velocity change between charges underneath.
As the target above indicates, the node is between 30.7 - 31.0
Here are the same charge weights shot today at 500 yards in a more traditional ladder method (note: usually you shoot 3 at each charge but since I already had the data at 100 I only shot one each)
Similar to the 100 yard test, charges from 30.7 to 31.0 change the least vertically.
To verify, I loaded 10 rounds at 30.8g and shot two 5 shot groups at 500 yards
Both 5 shot groups are under 0.3 moa
I’ll finish with some more background on the complete load development process and some notes on equipment in a following post.
Bottom line: both methods compared favorably to each other.
First, here’s the hundred yard load test a did a few weeks ago. This is my preferred method.
You load 3 rounds each at increasing charge weights and shoot them in order (not round robin). To find the accuracy nodes you look for group centers that deviate the least from point of aim when compared to adjacent groups. Also, flat spots in FPS data should correlate to the node. My notes on the target indicate avg FPS on the left, charge weight on top, group center distance to POA on right and velocity change between charges underneath.
As the target above indicates, the node is between 30.7 - 31.0
Here are the same charge weights shot today at 500 yards in a more traditional ladder method (note: usually you shoot 3 at each charge but since I already had the data at 100 I only shot one each)
Similar to the 100 yard test, charges from 30.7 to 31.0 change the least vertically.
To verify, I loaded 10 rounds at 30.8g and shot two 5 shot groups at 500 yards
Both 5 shot groups are under 0.3 moa
I’ll finish with some more background on the complete load development process and some notes on equipment in a following post.