Hey everybody, I wanted to start this thread to see everyone’s load development method(s) and what works for them. I’ve tried many methods including OCW, modified versions of OCW, the “Satterlee” method, my own version of both combined, and I’ve witnessed shooting buddies performing long range ladder testing. It also seems that everyone has their own way of doing things and some swear by their way, while others do equally well with a completely different strategy and method within the same discipline. I’ve tried many methods and have not been able to replicate the test results on separate days of testing with some of these methods.
Having said all of that, what do you guys do? I want to keep this thread on track and not have too much discussion or debates. I just want the down and dirty description of how you develop loads for your long range rifles. Whether it’s for hunting or competition or both. How many shots per charge? What charge increments for each load? Do you pay attention to ES/SD? What range do you do the testing? Do you repeat the test on separate days? Etc Etc. Thank you!
I feel a lot depends on just how much accuracy-precision one really intends to get out of their rifle. Some shooters are satisfied with 1 MOA, 3/4 MOA, etc. and some are not satisfied unless they're getting less than 1/4 MOA. In my case, since I don't shoot a fully customized rifle (factory rifle with a few mods to include a high end barrel), I look for ES's of less than 1/2 MOA and satisfied when getting consistently in the .3's, especially with my .308. Here's my way for getting there:
As part of my load development, I start by uniforming my brass. This starts with fire forming and goes on to uniforming primer pockets and turning necks and trimming to uniform length. Cases are annealed after every firing to maintain uniformity. I'll weigh the batch of cases and cull the outliers out so that the case volumes aren't too varied. Also, I'll sort my projectiles (quality one's like Berger or Sierra match grades) from base to the seating stem's contact point on the ogive so that seating depths will be consistent within +/- .001". I feel if I don't do these things first, it just makes it harder to see good results from OCW testing.
I like to start my OCW testing at about .010" off the lands. I'll load up 5 rounds each of charge weights in .3 gr increments. Though I've loaded up 5 rounds each, I'll fire just 3 rounds each at a different POA along a straight horizontal line. I'll use one of the extra rounds if I feel a shot wasn't done properly (like something to do with my mechanics that resulted in a POI that skews the test). For the first test, I'll choose a day for testing when weather conditions are relatively good, early in the morning, and is done at 100 yds to minimize the effects of outside variables. After this first test, I'll OCW test the same loads again at distance of 200 - 300 yds. and compare the results with the first test. I'll look for location and shape of the 3 shot groups. Once I figure I can identify an accuracy node, I'll load up 20 of them at that same seating depth and when I shoot them, I'll adjust the seating depths by .003" at the range to see what depth produces the tightest group. On another day, I'll repeat that to see if it compares that first test. Once I've found the seating depth that works well, I'll not change that load configuration until I see it's no longer working . . . which I've found can be quite a while (especially for a .308).
Note: Because of the projectile sorting that I do, when I use up a batch, I'll have to change my seating die setting so that my actual seating depth remains the same as the previous batch. I don't not pay any attention to jump once I've established a starting point (like the .010" I mentioned previously).
As far as chrono ES and SD's go, I only look to them for telling me how well I'm prepping my brass and weighing my powder. My goal is simply single digit SD's and low to mid teen SD's. I don't look to them to tell me anything about accuracy or precision on paper.