test results help: UPDATE 300 yard test

Re: test results help: UPDATE with seating depth

took it out to 300 yards today, testing .050 and .070 off the lands.

weather when I started was decent, but things got colder as I went, which may account for the second strings of shots being what they are.

Conditions:
Cloudy
temp: 42 starting, dropped to35 while I was shooting
Pressure: 30.06
humidity: 36%
wind. varible 2-5 MPH from 7 o'clock

Method: round robin, alternating back and forth between the 2 loads every shot to make two 3 shot groups. I then walked out and retreived the first target, posted the second, and then shot the second strings, reversing which load was fired first when alternating.

String one:
string1stats_zps7c8bcbac.jpg



String two:
string2stats_zps0809567a.jpg


I am not sure why I got the big vertical spread on the second groups, I think I may have sped up my shooting because it was getting cold, I was taking notes between shots, but that's about it, there were no called fliers

I also got decent chronograph data this time, here are those results:

.050 off the lands:
Average: 2918fps
ES: 26fps
SD: 10.55

.070 off the lands:
Average: 2922fps
ES: 57fps
SD: 21.33

as usual, comments, questions, suggestions always welcome
 
Explain group 1, string 1 to me. That cluster is what I would look for in a consistent load. Vertical is minimal and the horizontal is fine with inconsistent wind 2-5 mph.

I really like group 2 horizontal.

I am not sure what is going on with vertical spread since you are not playing with powder charge at this time. However, it is one of two things in my mind. Shooter or charge.

Let's go with charge weight. Right now I like string 1. I like the consistency across the board. Personally. I would go with this seating depth and adjust the charge slightly to see if that fine tunes it.

I don't know about the weather changing and messing up loads such as string 2 group 2. Unless you had a big pressure change the temp should not be enough to create that much change down range. Me, I would rule that out as shooter focus issue's. My LR loads were worked up 10 degree weather and have been shot up to 60 degree temps and it is still shooting .5 MOA or less. Just my thoughts anyway.

If you can work with string 1 a bit more I think you are super close to dialing it in....IMHO
 
Group one string one is the load I've been leaning toward, 44.8 grains of IMR 4895 under a 155gr VLD at .050 off the lands. Both of the groups with .050 off the lands were under .6MOA, so that does seem to be a good seating depth for my rifle.

I'm really not sure about string 2 group 2, I was shooting round robin for both strings, and every shot felt good, so I really don't know, probably just me having issues, though I'd think that would show up on both groups, shooting round robin for them...stupid Murphy getting in the way

I'm half tempted to try 45.0 grains of powder again, now that I found a decent seating depth, but not totally sure on that, I am right at the lower edge of the velocity range I want with my current load(2900+fps), and it is shooting well, and looks to have the potential to shoot even better.
 
I'm thinking that, before I try tweaking any more, I'll try the load that's 44.8 grains IMR4895 and .050 off the lands, and try it again, just do like 3 groups at 300 yards and see how it averages out...the load looks really god to me, so I think I want just a little more data before trying something else
 
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