Thread: Testing a conventional approach to load development

Originally Posted by McNotty

Just chose it because it’s the longest length of the lot. I don’t think it’s going to matter anyway.
Go with what you’ve suggested 1.852 as it’ll hopefully prove a point to some.

I am interested in doing the best I can to test the truth of the matter.


at present the average 3-shot group with 24.5gr 2206H (across different seating depths) is 0.6MOA
the smallest is 60% smaller than the average
the largest is 45% larger than the average

my current understanding is that with any particular load, you would expect + or - 60-70% variation in 3-shot group sizes. So what I'm seeing with the "tuning" of different seating depths is within the normal variation expected of any load. But I am very interested to do my best to test the process as so many people believe in it.

The current 21-shot group has a mean radius of 0.088 MRAD (0.88cm) and a predicted O95 of 0.37MRAD. The current observed (overlaid) 21-shot group size is 1.09 MOA (0.32MRAD).

If tuning works - a 20 shot group of the "best" load will have a smaller mean radius and a smaller observed group size over 20rd (overlaid) than the "worst" load.

If tuning doesn't work - both loads will be similar (within say + or - 20%) of each other for mean radius (more powerful) first and observed group size second (more variable), and also similar to the current overlaid 21rd group (although they should both be better than a group with 0.021" variation in seating depths - that's not consistency...)