Load Development - Process

[kthomas]

As for statistics I spent part of my career as a test engineer and I always hated statistics and when using it was forced to follow Test Codes so most of the times it was cookbook. The shooting world has gone from one extreme to another with regards to testing and statistical significance. We used to work with three or five shots but now we say that that number is worthless and we should have 20, thirty, or more. The reality is three or five may be all that is needed based on what is being looked at and with the understanding of the limitations of small sample sizes and how larger sample sizes would affect the results of the small sample size tested.

With todays equipment and components, I think many of us make good ammo not because of our process and "tests", but despite of it.

3-5 rounds for testing variables certainly "works" for what we are doing. Not because those are sample sizes statistically relevant to make the deductions we do, but rather because some of the variables we try to control and test just don't matter as much as we think they do.

1 5-round group isn't going to give enough information to conclude how one variable change affects the outcome, but a lot of times we prescribe too much influence on that variable we are trying to test anyways.

 

[Andrew863]

I use to turn over every stone, but now my hobby has turned into shooting and not just loading. All I do now is put 100 or so rounds on a new barrel, find a powder charge that gets me where I want to be for velocity. Then I go do a seating depth test and then see where I'm at. Most of the time I'm getting .300 to max of .500 and that is all I need for PRS.

 

[whatsupdoc]

While I do not shoot benchrest I shoot with a guy that does shoot and compete in short range bench rest.

He loads and does development at the range but when he shoots on a different day at a different place that
load development dont mean much as he has to tweak the load for the current conditions. He takes his best guess
for the first round of shooting and tweaks the load for the second round. Now when you add wind to the mix
the wind call's may carry more weight than that perfect load.

So you can develop a load all you want but the next day it may not be so developed.