Bullet weight: 55 gr
Powder: 23.0 grains H4895
Brass: Mixed headstamp
Rifle: Standard AR W/ 16 barrel (twist unimportant)
I've used the same load for 20 years. It had a 2900 fps give or take. Since I used range pick up, that caused some deviation. I put a new optic on it and wanted to zero it at 100 yds instead of 50. Took the chrono out and ran some so I could get a reading to make a ballistic drop chart. Avg velocity was 2550 fps on 20 rounds. (two sets of 10). Came home and picked out 10 pieces of brass with same headstamp. Measured the load by hand then back to the range. I called a friend to meet me there with his chrono. We set them up end to end. Same results. 2550 avg.
I cannot figure this out. Powder was stored on a shelf in the basement. 8 lb jug.
What's your thoughts?
Powder: 23.0 grains H4895
Brass: Mixed headstamp
Rifle: Standard AR W/ 16 barrel (twist unimportant)
I've used the same load for 20 years. It had a 2900 fps give or take. Since I used range pick up, that caused some deviation. I put a new optic on it and wanted to zero it at 100 yds instead of 50. Took the chrono out and ran some so I could get a reading to make a ballistic drop chart. Avg velocity was 2550 fps on 20 rounds. (two sets of 10). Came home and picked out 10 pieces of brass with same headstamp. Measured the load by hand then back to the range. I called a friend to meet me there with his chrono. We set them up end to end. Same results. 2550 avg.
I cannot figure this out. Powder was stored on a shelf in the basement. 8 lb jug.
What's your thoughts?