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Confused over Berger seating depth test

On calibrating anything you adjust coarse, then fine.
Berger's test works for any bullets, as long as you're testing with a charge that allows you to see seating changes as dominate to results. Then go to powder development, or already developed.
 
On calibrating anything you adjust coarse, then fine.
Berger's test works for any bullets, as long as you're testing with a charge that allows you to see seating changes as dominate to results. Then go to powder development, or already developed.
I’m thinking since I know I’m about .01 in the lands that I should start there and back off .005 for each new group . What do you think?
 
As a load developer, I have found that most of the time, Berger or Hornady "accuracy type" bullets in hunting rifles like around .020" off the lands. This includes Hybrids and VLDs. So I always start at .020" and test powder charges. If I need a small tweak I'll test .015, .020, .025. If I need a big improvement I'll test .025, .050, .075, .100.

What I do for LRBR rifles really only applies to LRBR rifles......
 
As a load developer, I have found that most of the time, Berger or Hornady "accuracy type" bullets in hunting rifles like around .020" off the lands. This includes Hybrids and VLDs. So I always start at .020" and test powder charges. If I need a small tweak I'll test .015, .020, .025. If I need a big improvement I'll test .025, .050, .075, .100.

What I do for LRBR rifles really only applies to LRBR rifles......
Our matches are 300 and 500 yards from bench . No hunting guns . Please tell me what you do for benchrest ?

Thx

Mark
 
I ran their test on Saturday for a hunting rifle. .010 / .050 / .090 / .130 jump six rounds each shooting groups of three just like Berger suggests. The .130 had the smallest group (and aggregate) with .050 in a fairly close second place. .010 jump finished in last place

140gr VLD H

Just for fun I'm going to give .050 and .130 another run to confirm
Normally from that, i would pick one of the two and try .005 up and or down. If .130 shot good, id load up .125, .120, maybe .135. Maybe .115. Kind of a fine tune around that .130.

I got lucky in my gun twice, that at max mag oal, with the 210 vld and 180 elite hunter in my 300 wsm, they shoot ragged single holes when the powder charge was found. Both are jumping .120+. But i did move to single feed the 210’s with next higher node at .030 off.
 
As you change the CBTO, do you see the groups shrink or expand in a uniform fashion? I have been using the Berger method and I do not find the group size uniformly changing? I figured the groups would shrink to the sweet spot and then start to expand. Tha's not what happens to me.
 
Mine only seem to shrink or expand when close to ideal and move in small increments.

Like .025, .030 are somewhat expanded groups. Move to .035 and see it shrinkng like two very close one just off. .040 it was a round hole. .045-.050 it started opening

Then again some setups i just cant seem to get to shoot well with bergers lol my guess is powder isnt ideal or im trying to force the high node when the low node would be more accurate. Maybe its my shooting skills with lighter long barreled guns. Not sure
 
Our matches are 300 and 500 yards from bench . No hunting guns . Please tell me what you do for benchrest ?

Thx

Mark

I have a pretty good idea of what will work for my LRBR rifles. I also consult with those I compete with who consistently do well.

In a 6 BRA I first run though the powder in .2 grain increments (.4 for a 300 SI or WSM) with a seating depth that commonly works. Usually +.006 from touch for the 6mm and +.021 for the 30s. There is usually a high node and a low node. Typically, the low node shoots best to 600 and the high node shoots best at 1000, but that still needs to be checked.

When I find the best powder charge I then check seating, and that can take some time. I'll start with the jam and test, then go to the jump and test. I start with .003 increments. Roughly from .021 jam to .021 jump. There will be a couple of seating nodes.

After I find the best seating depth I'll refine the powder charge, checking in .1 grain increments for the 6 and .2 grain increments for the 30.

That is my basic procedure, probably very common in LRBR. It assumes you have all the other stuff sorted out like neck tension. Neck tension is worth testing as well.

Of course, like I found at the last match, sometimes even with the most thorough development process, things can still go sideways. With BR, EVERYTHING has to be as perfect as possible and we can leave nothing on the table.
 
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I have a pretty good idea of what will work for my LRBR rifles. I also consult with those I compete with who consistently do well.

In a 6 BRA I first run though the powder in .2 grain increments (.4 for a 300 SI or WSM) with a seating depth that commonly works. Usually +.006 from touch for the 6mm and +.021 for the 30s. There is usually a high node and a low node. Typically, the low node shoots best to 600 and the high node shoots best at 1000, but that still needs to be checked.

When I find the best powder charge I then check seating, and that can take some time. I'll start with the jam and test, then go to the jump and test. I start with .003 increments. Roughly from .021 jam to .021 jump. There will be a couple of seating nodes.

After I find the best seating depth I'll refine the powder charge, checking in .1 grain increments for the 6 and .2 grain increments for the 30.

That is my basic procedure, probably very common in LRBR. It assumes you have all the other stuff sorted out like neck tension. Neck tension is worth testing as well.

Of course, like I found at the last match, sometimes even with the most thorough development process, things can still go sides ways. With BR, EVERYTHING has to be as perfect as possible and we can leave nothing on the table.
Thank you sir ! I will try this .
 

Thanks; How did you get there? I still don't see it on the their site.

Ah, found it. Buried pretty well: Main page, Technical Support (at bottom of page), Shooting Knowledge (again at bottom), select article.
 
Thanks; How did you get there? I still don't see it on the their site.

Ah, found it. Buried pretty well: Main page, Technical Support (at bottom of page), Shooting Knowledge (again at bottom), select article.
I found it by accident the first time. I just Googled it the second time.
 
Ok ! So Berger states that with a target rifle you should start .01 in the lands and then move back .04 , .08 and then .12 ! Holy cow that’s a lot . They state one of those distances will shine over the others . Here’s the confusing part . Erik Cortina shoots Berger’s and he says to start with touching the lands and then move back in .003 increments till you find the sweet spot which he says you will get to within .03 !!!!

So you guys see why I’m scratching my head ! What’s up with this HUMONGOUS DISCREPANCY????

Thx

Mark
Everyone HAS, a different approach ! With most of, the Secant Ogive designed Bullets like, Hybrid's, Classic and Elite Hunter, Berger's, and, a LOT of the Sierra & Hornady Bullets that, are Secant Ogive designs,..
First, I find, my Rifle's, "Jam Point" then, back off, .015 to .020 from Jam and Start working up Loads to find my rifles, Maximum, SAFE Pressure and the Velocity that's, estimated by the Data that, I've used, using a Chrono.
After finding, a SAFE Powder Chge, I "move' the Bullets "back" in, in .010 to .015 increments and usually find my most accurate Loads at, .025 to .070,.. "off" Jam. ( found THIS, to Work well, in my, .243 Win., 6 XC and 6.5 Creed )
Remember that, the Throat / "Leade area" is, CONSTANTLY "moving" a little, every few shots and "may" need further "Tuning" later. I start my serious load "Work up" at about, 100 rds thru Barrel. After cleaning a couple of times and, the barrel's "Breakin in" is,.. DONE.
My .270 WSM shoot's, the 140 gr. Berg Classic Hunters at 3,185 FPS into, 1/2 MOA and 3/4 MOA on my "Bad Days" at, .110 "Off" the Lands ( Magazine Length for, a Tikka T-3 ) and the recommended COAL from, Berger.
Tangent Ogive, H-VLD's and VLD design's, can take a bit more, "Tuning" thus, Berger's "moves" in .040 increments and then, fine tuning from, there. Watch Eric Cortina's Vid's., on YouTube. Good Luck !
 
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My contention is that you calibrate things with coarse adjustments first, before moving to fine adjustments.
Berger laid this method out for you
I’ll have to try that on next load . I’ve already loaded 50 that are .01 in the lands (newbie mistake) and it’s not a starting load so I would feel much safer moving back .003 at a time till I get to say .025 jump . I think moving back .1 would raise pressure too much .
 

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