Help with Reloading Data

[kcary1776]

All, I could really use some help here. I'm relatively new to fine tuning loads to get consistently small groups. For the first time ever I have a rifle that I believe I can tune a load to shoot small groups. After my ladder testing, the image below outlines the loads I decided to test. I know it's a lot of loads but I have some new Lapua brass that I wanted to fire form so I figured what the heck. Would anyone be willing to take a look and advise on where to go next? Load 1 seems obvious to test further, butI would really like a little higher velocity if possible. However at Load 7 I can't tell what is happening with that group. Is it possible that the higher 2900 fps velocity is where the load starts to come apart? If I overlay all these groups while taking exception to one flyer on the right on load 3 and one flyer on the left on load 7 (if indeed those are flyers) that leaves me with a roughly 1.170" 35 shot group. That leads me to believe that this powder, primer, and bullet combination are promising. But again I am relatively new to the fine tuning of a load and am not very sure what I am looking for at times. Any help would be greatly appreciated. Thank you for your time in advance.

 

[simonp]

I think I would be looking at load 4, see if the numbers and the target is consistent, if so then perhaps a little adjustment in the seating depth will tighten up the group.

 

[Nunna]

Have a look at the attached graphs, a tool I built for myself when doing load testing and this also shows that Load 1 and 4 is most probably the best to peruse for smaller refinement although Load 4 was very good with one outlier as seen in the first graph. You can see that the results on target is supported by both the SD and ES in the data and graphs. As SimonP above commented, I would look at playing with the seating depths on these two load to see if you can tighten them up.

 

[R_A_W]

You will likely be able to tighten up the groups and SDs with a different primer. #41s are designed for semi/full auto & have thicker cups and more clearance between the anvil & the primer compound.

 

[918v]

You’re way over pressure. Play with load #1 and don’t go higher.

 

[Doom]

It does appear you are significantly over on pressure but the degree to which this is true depends on your barrel length. 2825 fps is about the max you should see in a 26" barrel and around 2775 in a 24" barrel. It unusual to see #41 primers but I assume this may be because of pressure signs in other primers.

As for velocity and group size, what is your use and requirement for this load and rifle?