Ladder Tests

[USMCDOC]

I thought a ladder test was using different loads like 23.1, 23.3, 23.5 etc. Then find the flat spot where they landed on the target at the same level to find the middle of a node. Maybe I am reading this wrong. Matt

i went up at one tenth for each test load. i already knew a ballpark area.. going up .3 at a time is just too much of a jump with the .223.

 

[dkhunt14]

i went up at one tenth for each test load. i already knew a ballpark area.. going up .3 at a time is just too much of a jump with the .223.

I wasn't sure what our were doing. I just used a .2 as an example. I don't think .2 would be too much of a step for a .223. It would only change velocity about 10 to 14 feet a second. Then I would test,in between nodes with 5 shot groups. I believe Ray is right. Matt

 

[USMCDOC]

I wasn't sure what our were doing. I just used a .2 as an example. I don't think .2 would be too much of a step for a .223. It would only change velocity about 10 to 14 feet a second. Then I would test,in between nodes with 5 shot groups. I believe Ray is right. Matt

That is what i will be taking to the range later today.. 4,5&6 off of target #1, but i am also going to try off target #3 numbers 4 & 5.

 

[jrb572]

That load would be 27.0 grs of 2KMR.

I wouldn't worry about what the charge is as long as I was getting the velocity that would work.

 

[USMCDOC]

I wouldn't worry about what the charge is as long as I was getting the velocity that would work.

It is around 2900

 

[mikecr]

Have you tested for & set best(rough) bullet seating yet?

Mike, the load was set at 10 in..

Is that a yes, or no?
Why 10thou ITL?

 

[Riesel]

That is what i will be taking to the range later today.. 4,5&6 off of target #1, but i am also going to try off target #3 numbers 4 & 5.

I, for one, am anxious to hear and see the results.

 

[USMCDOC]

Is that a yes, or no?
Why 10thou ITL?

From past experience.. i have always started at 10 thou into the lands..

 

[USMCDOC]

Don't mind that one that has all that black around it.. that was from another group.. ended up worth nothing that one was!

A storm front has been moving it.. where i am shooting the tests at are in a hollow.. no flags and it is a very hard place to get mirage at too.. so i just tried my best at keeping the elevation good..

 

[Zero333]

On your first post, on target #1, I like 1-2-3 because they're very close to each other.

Some say windage doesn't matter when deciphering ladders, and I agree that a small amount of windage probably doesn't matter. But I don't like to see more windage poi shift than what the wind should of affected the shot.

 

[JohnMill]

Yes.. on Target #1 i am going to look real hard at 5 & 6.

Say Doc, where did you get that ladder test from? The one I use is from JB1000's article on the tech page. I see one similar here that Audette used ( and I'm sure there are others). The point of the ladder test is to find a load that shoots near the same vertical for numerous shots. Shooting one shot of 10 different loads only shows they shoot different verticals but does not show the average vertical spread of any one load.I do not see that you have eliminated any "bad' loads.
Erik Cortina also has a good system on this page on how to find a good load at 100 yards. He explains the objective well.
JB does too but you have to read it more than once His training was in science or statistics or some such.
Hope this helps

 

[USMCDOC]

Say Doc, where did you get that ladder test from? The one I use is from JB1000's article on the tech page. I see one similar here that Audette used ( and I'm sure there are others). The point of the ladder test is to find a load that shoots near the same vertical for numerous shots. Shooting one shot of 10 different loads only shows they shoot different verticals but does not show the average vertical spread of any one load.I do not see that you have eliminated any "bad' loads.
Erik Cortina also has a good system on this page on how to find a good load at 100 yards. He explains the objective well.
JB does too but you have to read it more than once His training was in science or statistics or some such.
Hope this helps

I used the one shot method.. increasing each load by a tenth.. since i already knew a the bingo point

I just tried to isolate it with this FC 15 brass that i have gotten. The load don't like turned necks, i can tell you that.. it likes sizing.. expanding and then sizing again.. tension close to 2.5K.
I have seen some of the one Erik as been discussing.. but i have not read the one from JB1000, i will have to take a look at that.. next is to take it out to distance as see how it acts.. which is going to be next month before i can do that..

 

[Raythemanroe]

I used the one shot method.. increasing each load by a tenth.. since i already knew a the bingo point
View attachment 990282
I just tried to isolate it with this FC 15 brass that i have gotten. The load don't like turned necks, i can tell you that.. it likes sizing.. expanding and then sizing again.. tension close to 2.5K.
I have seen some of the one Erik as been discussing.. but i have not read the one from JB1000, i will have to take a look at that.. next is to take it out to distance as see how it acts.. which is going to be next month before i can do that..

You can tune like Cortina, I start my load testing at 200 yards.. Well, because my local range is 200 yards.. I line up a bunch of level targets and look for nodes working @ 2-3 grains and three shot groups.. You can clearly see how they print to the point of aim.. When you find a node usually two, three print similar.. I work from the middle of the node and using a chronograph start seating testing.. Chronograph helps verify findings.. Once a load works @ two hundred I revisit powder tuning before testing at 1k yards.. Point blank tuning doesn't always establish the best load at long range, many times another node just works better at 1k.

I would like to add I start my tuning borrowing proven loads from folks.. Speeds up the process..lol

Ray

 

[USMCDOC]

Well, i am going to shoot it one more time on some fired brass and see how it goes.. and then from there.. stop.. prep a lot of brass so that i can get it all sorted out..

 

[mikecr]

When you do start over, because you really have nothing to go forward with, I recommend Berger's full seating testing -before shooting ladders.
http://www.longrangehunting.com/for...accuracy-berger-vld-bullets-your-rifle-40204/

Also, there is no reason I can think of that incremental powder changes and ladders would apply only for vertical. And Horizontal, as caused by your combination, is just as important to accuracy.
It's been said that seating and tension affect horizontal. I don't know this to be true, but I know that in fine adjustment they act to shape grouping. In coarse adjustment, they can open/close grouping like shotgun chokes(far more than powder).

 

[USMCDOC]

When you do start over, because you really have nothing to go forward with, I recommend Berger's full seating testing -before shooting ladders.
http://www.longrangehunting.com/for...accuracy-berger-vld-bullets-your-rifle-40204/

Also, there is no reason I can think of that incremental powder changes and ladders would apply only for vertical. And Horizontal, as caused by your combination, is just as important to accuracy.
It's been said that seating and tension affect horizontal. I don't know this to be true, but I know that in fine adjustment they act to shape grouping. In coarse adjustment, they can open/close grouping like shotgun chokes(far more than powder).

I have often wondered that myself.. But Lady Wind is always there in abundance like like the Fat Lady singing.. but the story is over just because she is! Hence i have not ever really paid that much attention to the dispersion to the left or to the right.. but i would say that i have a feeling that the theory has merit.. in my mind at least.. Don't ask me to support that .. it is just a gut thing ya know..

 

[ranger3]

On target number four, bullets 2 4 6 & 8 look good, if they are somewhat similar that is a good group no vertical dispersion. If The Other bullets on that Target are the same, Then I would adjust seating depth slightly.

 

[mikegaiz]

I have found when using a ladder test and finding only vertical stringing means change bullet or powder. usually bullet. Here is what I look for. Then I test in the horizontal node. The velocity in noted next to the # shot. this shows almost 70 fps with only 1/2 in. vertical.

 

[USMCDOC]

I have found when using a ladder test and finding only vertical stringing means change bullet or powder. usually bullet. Here is what I look for. Then I test in the horizontal node. The velocity in noted next to the # shot. this shows almost 70 fps with only 1/2 in. vertical.

View attachment 990416

And out of that i probably would have further investigated number 8 & 9.

 

[mikegaiz]

Close # 7 set two IBS 1000 yd records this summer.