Chono ?

[wisconsinteacher]

Well I got my chono today and will start playing with it in the house with rubber bands and then with my bow. Other than fps, what other function do you like to use and why? I want to be able to use the Beta Master to its fullest. The reviews said that the directions were hard to read and they are right. I need to read it when I am fresh and ready to focus.

 

[DrMike]

Check consistency of your loads by noting the standard deviation. SDs can be strange if there is not a sufficiently large sample. So, when you have completed your initial assessment of a load, prepare ten or so rounds and get a true SD. The SD has proved much more valuable to me than the Extreme Spread.

 

[wisconsinteacher]

I know my chono will spit out SD and ES along with the low and high of 10 shots but is there a webpage where you can take your pen and paper notes and then plug them in so it is more user friendly?

 

[JD338]

The chronograph will allow you to find consistency in your loads. Low ES and SD's is the first step in achieving top accuracy.

JD338

 

[DrMike]

I carry a separate notebook for each cartridge I'm loading. These notebooks accompany me to the range where raw data is noted. Then, I can work it over at home as I analyze the data. There are perhaps web sites, but none that are able to take the place of what I'm compiling.

 

[wisconsinteacher]

So you just do it long hand?

 

[FOTIS]

Microsoft excel works for me

 

[wisconsinteacher]

I just did a quick look and found this. I think it would work great.

http://easycalculation.com/statistics/s ... iation.php


What is your goal number for SD. I know lower is better but at what point are you happy?

 

[JD338]

I strive for single digit SD's.

JD338

 

[DrMike]

My completed data is stored in an excel version on my computer. For working at the bench, however, I use a pencil and my data books.

 

[Guest]

If you have much skill at all with Excel you can create a spreadsheet formula that will calculate all your statistics for you. That's what I do, and I have the same Beta Master Chrony you just bought (wise choice!). When I'm at the range, I set out my targets and label them alphabetically. I use a consistent numbering scheme where I count the different bullseyes on my 5-bull sight in target in a "Z" pattern, starting at the top left and ending at the bottom right. So A3 is the center bull, and A5 is the bottom right, and so forth. Then I can just record the specific target aiming point and the velocities for the various shots in my notebook at the range. I use a single notebook and flag the pages for dates, unlike Dr.Mike who uses a different book for each. When I get home, I put the shot velocity and group sizes into the Excel sheet. I have it set to automatically calculate the mean, SD, and ES. At one time, I played with trying to find a statistically significant difference between the mean group size for different loads, so I had both a simple T and ANOVA set up on an excel sheet. I got tired quickly of trying to accumulate enough data on enough consistent days (weather-wise) and scrapped that project, though. But the point is, Excel is very robust for this type of work and will do all the hard parts for you with pre-programmed formulas.

 

[Hegland]

I keep spreadsheets of what I write down while at the bench. I suspect you're probably familiar with the Average, Standard Deviation and Max/Min functions in Excel; these will get you the most useful information. As dubyam noted, there is a whole statistical tool pack available, but my experience matches what he found regarding sample size.

As several have stated, I usually keep my eyes glued to the SD. I take it another step and convert it to a percentage of the mean velocity, and in most instances the most accurate load will achieve an SD under 1% (sometimes well below 1%).

If you need any help, feel free to ask or shoot any of us a PM.

The only way I've found to get around writing down readings is to get one of those fancy chrono's like Mr. Price, which will dump directly into Excel.

 

[DrMike]

Even though my Oehler prints out all the data, I still write down the information obtained in my notebook. I may tape the output from the Oehler printer on the page with the load information, as I do with the target. However, the information is still written down. Hegland brings up an excellent point. I take it as a given that a SD of 1% or less is not only desirable, it is the goal of each test. A low SD holds the promise of accuracy.

 

[JMUPT]

I have this http://www.midwayusa.com/product/858623 ... oaders-log I haven't used it yet but seems like it's a good way to keep everything organized and written down.