??? Correct process; adjust seating depth

Country Bumpkin

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Sep 22, 2015
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Boise, ID
Hoping someone can give me some best practices for adjusting seating depth during load development.

Current Progress:
7RM
22" Proof
8.5 twist
.6-.7 MOA
Barnes 160 TSX
66.0 RL26
COAL 3.185 SAAMI

SO, what I do NOT have interest in... is making minuscule adjustments that will require 2 years and 37 range trips to finally see any results (in hopes of finding that unicorn perfect load).

If I can get away for Trying 4 different COAL's and finding a consistent load at or under .5 MOA, I'll be over the moon.

So, is this achievable given my current .6-.7 load, by adjusting seating depth?
 
Pm if you want to go to my range. Has 500yd setup.
1. trip to test for vertical nodes
2. trip to test best node with 5 groups .010" apart
Just for a quick load
 
Seating depth is more critical than powder charge, it's worth investing the time in!! You can usually nail a node range in a few depths then two more .005 on either side to see if you on it or need to tune a little more.
 
So do the initial jumps span .010 per set?

Start at current charge and depth, .010 closer to lands for each group until I see pressure signs (pick the best node and go .005 on either side from there)?
 
I differ from bg. I think the powder charge to find the node is the most important while the seating depth fine tunes after. Eric Cortina has a nice write up on load development. Find powder charge .005" off lands. Seating depth backing away from lands in .010" increments. Not the only way to do it though
 
Well shoot, I'm bass-ackwards from that approach. I wonder if a guy would ultimately end up at precisely the same charge and depth if they tried both strategies independently.
 
You can shoot your barrel out trying to keep a barrel in tune with just powder if your not on your seating node especially your vertical.

You have to do seating depth with Barnes differently than some, you want to start in the .050 of range and go .025 increments from there and you'll find a sweet spot. Bergers I look at 10 in the lands 10 off then .010 increments then .005 on either side of the node.
 
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If you have a Chrono, look at this video from 6.5 guys. It may have what you are looking for.

 
I use the Saterlee method for every rifle I start loading for. Finds the node super fast and then a few seating changes and your good to go. For my 1000 yard match rifles I do just a little finer adjustment on seating depth. Works fast and simple.
Shep
 
I do a node pressure work up at distance with 0.020" jump. Then do a refined 3 shot group test with 4 power charges. If that doesn't work, I do the seating depth tests. I can usually get it done in 30 to 40 rounds.
 
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