Thank you. I'm not a statistician but I think it's possible this does not show a statistically significant difference, even if the sample size is kinda small in the grand scheme of things. So to you I say, damnit, why'd you post that and make me feel like I routinely waste time and money?
In absolute terms,
@straightshooter1 's un-annealed versus annealed brass raw percentage difference numbers are pretty striking.
- At 100 yards, SS's data shows a 47+ percent increase in group size in un-annealed brass (.34 * 1.48 = .503)
- SD of un-annealed brass increased 76 percent (9.6 * 1.76 = 16.9)
Inside of 500-600 yards, though, the practical differences arguably don't matter much for PRS-style competition with PRS-common calibers. BUT the hit probabilities separate more as range increases.
At distance, AB Quantum "Weapon Employment Zone" modeling shows the following probability of hitting a 1-MOA circular target with wind set to 0MPH and everything else "perfect" for the shot (this data for 6.5 Creedmoor 140 ELDM at 2775fps):
- 1000 yards (11"):
- 93% with SD=9.6 and .3-MOA accuracy @100
- 70% with SD=16.9 and .5-MOA accuracy @100
- 500 yards (5.5"):
- 100% with SD=9.6 and .3-MOA accuracy @100
- 98% with SD=16.9 and .5-MOA accuracy @100
I haven't encountered many 1-MOA targets in the matches I shoot, but neither have I ever shot a match with no environmental effects - especially wind - on my shots. Adding in a little wind variability to the WEZ model drops percentages anywhere from a little (constant wind velocity) to a LOT (gusty, switchy), as one would expect.
Fwiw.
