??? Correct process; adjust seating depth

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?
Take your time and do it right. Use the Berger seating depth test and then go in increments of .003 to find the sweet spot. If you go more than that you may miss it. I do this in 3 range trips including finding a node with the powder being used.
 
You can go to youtube and look up panhandle precision as well as others that will explain the process very well for you . I myself don't believe that there is any real short cuts if you are going to reload and want to wring out the best in you and your rifle . If you just want a fairly good group buy some factory loaded ammo and have fun shooting to see what does the best for you and your rifle . Keep your rifle clean and cool , Some of the Federal offerings will do you well in the 160 - 180 weight range .
 
Here is an example of seating depth at 300 yards with rough .015" graduations. All the groups looks crumby except one dialed in nicely. Sometimes the sweet load will sneak up on you
IMG_4137.JPG
 
Good lesson here. We have many ways to find loads that work for all of us. Try a few and see what works for you
 
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?
Hi Country, I'm from Boise also. Do you shoot at Black's Creek, Parma or ?? Maybe we can shoot together this Summer unless we are all still ordered to stay-in-place 😊 -Rick
 
So, is this achievable given my current .6-.7 load, by adjusting seating depth?
Absolutely!

I do all my LD for any of my cartridges with any projectile the same way.
Start at 10thou off the lands, go through the charge range, pick the best group of 5 shots, change CBTO for that load to 5thou, 15thou & 20thou.
Once I have found the best from those changes I will then again do a few incremental powder charge changes like -0.1gr, -0.2gr & +0.1gr, +0.2gr.
This has never done me wrong & I have never had to seat any deeper than the 20thou without getting the result even with Berger VLD's, however if I still wasn't happy I would go further than 20thou.

Imo though you should be working of CBTO not COAL, as all projectiles have different ogive shape you want to be working from a known distance to or from the lands, by measuring to the point how do you know how far you are away from the lands??
And as mentioned this changes for each projectile!
 
Absolutely!

I do all my LD for any of my cartridges with any projectile the same way.
Start at 10thou off the lands, go through the charge range, pick the best group of 5 shots, change CBTO for that load to 5thou, 15thou & 20thou.
Once I have found the best from those changes I will then again do a few incremental powder charge changes like -0.1gr, -0.2gr & +0.1gr, +0.2gr.
This has never done me wrong & I have never had to seat any deeper than the 20thou without getting the result even with Berger VLD's, however if I still wasn't happy I would go further than 20thou.

Imo though you should be working of CBTO not COAL, as all projectiles have different ogive shape you want to be working from a known distance to or from the lands, by measuring to the point how do you know how far you are away from the lands??
And as mentioned this changes for each projectile!
I agree that the COAL has potential accuracy problems unless you have high quality controls. 🍻
 
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?
I would recommend you stop measuring COAL (Cartridge Over All Length) and get a comparator such as the Hornaday LnL kit and start measuring CBTO (cartridge base to ogive). This is the critical measurement to use for seating depth. If you are already getting .6-.7 MOA consistently, you are likely at the point of fine tuning by making .002" adjustments in CBTO measurements.
 
I like the powder charge/pressure/ladder test first. Then adjust seating depth.
Are you running this gun as a repeater?
Yes, stuffing the internal box full. It's primary function is as a lightweight Hunter (not a true long range cannon), so follow up shots over maximum potential range/accuracy.
 
Hi Country, I'm from Boise also. Do you shoot at Black's Creek, Parma or ?? Maybe we can shoot together this Summer unless we are all still ordered to stay-in-place 😊 -Rick
Interestingly, I just shot at the Blacks Cr range for the first time two weeks ago. Fell in love with the place, now we are on lockdown. I used to be averse to paying for shooting spots because of all the public land we have... but with recent population swell I got nervous shooting out in the desert. I've not had the opportunity to try Parma yet but I've heard good things. If you know of any safe spots in the desert we might try to link up soon.
 
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