Some days chickens, some days feathers. Today it was "chickens". :)

This thread will relate the results of shooting the Anschutz .22 Hornet at 100 yd. The details on the "day at the range" will be relayed in the Campfire.

I shot two bullet types:
1) My cast lead (see here: http://thehunterslife.com/forums/showthread.php?t=18311)
2) Hornady factory (see here: http://thehunterslife.com/forums/showthread.php?t=18245)

The cast bullets were very disappointing. Here's the 5-shot group. Note the red arrows.


That's about a 6 1/2" x 8" 5-shot group. Pretty grim. I'm not sure what I should do about it at the moment. Here are the MVs: 1880, 1842, 1845, 1878, 1799. The average is 1848.8 f/s. Standard Deviation is 33.04 f/s. The MV goal was 1633 (according to QuickLOAD). The charge was 3.89 grains of TrailBoss. Gotta come up with a different charge.

On the other hand, the factory Hornadys were pretty good.


That's about an inch high by and inch wide. I like that. Probably could do better with more effort. Oh yeah; there was a wind of between 10 - 15 mph, almost directly from behind, but slightly from my right shoulder. Note the tight MVs: 3022, 3022, 3032, 3037, 3039. The average is 3030 f/s. Standard deviation is 8.08 f/s. The 3030 f/s is 'good' :) and the standard deviation of 8 f/s is very good. I don't often praise factory ammo, but this will be difficult to beat with handloads.

I didn't shoot at longer ranges, AND I chose not to shoot any more. I'm saving what I've got!

Paul

Here's my statistical analysis of the groups produced by shooting these two bullets. First the cast bullets:


Then the Hornady 35 grainers:


Of primary interest to me is the value for the Area of the 95% Confidence Ellipse seen in cell "F16". For the 5-shot cast group, that value is 76.35 square inches; for the factory group it is 1.04 square inches. What that values predicts is the area into which I could expect the next 95 out of 100 shots to go at 100 yd.

If you look at cell "B3" you will see the value of "Student's t". That value is based on the sample size. The larger the sample size, the smaller the Student's t value. The Student's t value is a MULTIPLIER of the variance observed in the shot string. Therefore, the greater the number of shots you are using to determine the parameters (average, variance, etc.) the better the estimate of 'reality' you will have. Since the smaller the sample size the less confidence one has that the samples used actually REPRESENT REALITY, you have to broaden the PREDICTED parameter.

Taking "max spread" as an indicator of THE BOUNDARIES AROUND where the "next bullet" is going to hit is "optimistic" at best. Put another way, it's fooling yourself. There are PLENTY of people in the world that want to fool me, I don't need to fool myself. What I want to know is my BEST GUESS at where the 'next' bullet is going to hit based on where the last "X number" of them hit. Max spread is "easy", but it's not "good" for making that prediction/guess.

Paul

PS - If you have MicroSoft Excel and would like a copy of the spreadsheet so you could perform your own calculations, shoot me a PM and I'll email a copy with some instructions to you .

Paul