First Ladder Test - need help

[Mikecr]

I see no reason to dismiss horizontal (any more than vertical).
To get ladders down to a fewer variables, You need to take your cases to stable capacity(fireformed), and of course weigh the powder.
While you're fireforming, you might as well run Berger's seating test, and pick better seating, so that later ladder testing won't be spraying shots all over due to poorly chosen seating on top of everything else.
Shoot the ladder in pristine conditions, fouled & timed shooting, using good rests and a good long range scope. I would recommend across a chrono to normalize your data.

There is a good bit of work to be done before shooting an effective ladder.

 

[Kennibear]

Mikecr

You are absolutely right in what is needed. You are the expert here. I need velocity for most of my data to get anything meaningful. But my intention was to derive something useful from the target. Except #14&#15 nothing is really grouped.

I actually find the target pretty vague. Maybe better to re-shoot it and hope for better results.

KB

 

[live2huntmt]

I loaded up 5 rounds of each (11) 65.0gr H4350 and (14) 66.5gr H4350 and shot them at 200 yards tonight. 67 Deg F, 30.29 inches and dropping, 25% humidity, Winds NNW @ 3 MPH, 3315 elevation. Shot off a concrete bench using a bipod and rear bag. Tikka T3 300 WSM w/ Vortex PST 6-24x50 in Vortex Precison Matched 30mm Ring Set.

Once fired, neck turned, weight sorted Norma brass, sized w/ Redding Type S bushing die, shoulder bumped back .0015 using Redding competition shell holders, bullets weight sorted and seating individually to same CBTO using Redding Micrometer Seating die.

Here is the 65.0 grains of H4350 (shot 11 on my Ladder Test picture)

 

[live2huntmt]

Here is 66.5gr of H4350 @ 200 yards (shot 14 on my Ladder Test) .... totally not acceptable. What am I doing wrong?

 

[Barrelnut]

The 66.5 looks good except you seem to have two separate groups. IMO you are pulling the rifle somehow. The Tika is probably light and a 300 WSM, at that powder lever with the 180 AB, has some punch ( I shoot a 300 WSM myself). I would make sure the rifle is not jumping on you. Pull in square into your shoulder with the same pressure each time ( don't try to shoot it free recoil). If the rifle is jumping significantly left after each shot, try moving your left hand from the rear bag and holding the from of the stock a little. Sometimes this is how you have yo shoot a lighter weight rifle.

 

[Kennibear]

The #11 load has an ES of 85fps which is a lot. So that group maybe explained away. But #14 is ES= 34fps and while not great it is not terrible. Your technique could be the culprit but lately I've started checking my scope screws as I found the 1 1/2X Weaver on the 45/70 was loose (after only 47 years of abuse).

Put a sandbag vertically between the butt plate and your shoulder and see if that helps. It absorbs some of the recoil but it also serves as dead weight at the butt end to quiet down movement.

KB

 

[Kennibear]

One other thing. Switch your primer to something milder. Maybe a CCI #250. That may help. It's a long shot, well, a medium range shot in the dark anyhow...

KB

 

[justgoto]

Here is 66.5gr of H4350 @ 200 yards (shot 14 on my Ladder Test) .... totally not acceptable. What am I doing wrong?

View attachment 34820

That is exactly what I would have expected from shots 14 and 15, if wind wasn't placing them at the outer edge of your ladder. You're in a horizontal vibration.

The other target displays too extreme of a velocity spread. By recording the velocity of each shot during the ladder test, you might have been able to predict that.

 

[live2huntmt]

That is exactly what I would have expected from shots 14 and 15, if wind wasn't placing them at the outer edge of your ladder. You're in a horizontal vibration.

The other target displays too extreme of a velocity spread. By recording the velocity of each shot during the ladder test, you might have been able to predict that.

Sorry....I should have listed each shot's velocity during my Ladder Test...here they are:

300 WSM, GM215M, H4350 60.0-67.0, CBTO 2.250", COAL 2.880"

1) 60.0gr 2726 fps
2) 60.5gr 2754 fps
3) 61.0gr 2801 fps
4) 61.5gr 2818 fps
5) 62.0gr 2842 fps
6) 62.5gr 2861 fps
7) 63.0gr 2892 fps
8) 63.5gr 2936 fps
9) 64.0gr 2943 fps
10)64.5gr 2956 fps
11)65.0gr 2956 fps DUP 1
12)65.5gr 2989 fps
13)66.0gr 3016 fps
14)66.5gr 3009 fps
15)67.0gr 3058 fps

"The other target displays too extreme of a velocity spread. By recording the velocity of each shot during the ladder test, you might have been able to predict that"

- Can you please teach me how to predict that by the above data? Thanks!

 

[live2huntmt]

One other thing. Switch your primer to something milder. Maybe a CCI #250. That may help. It's a long shot, well, a medium range shot in the dark anyhow...

KB

I actually tried this yesterday with the same two powder charges, but used GM210M primers instead of GM215M. Here are the targets & velocities....what do you think?

65.0 gr H4350 GM210M




66.5 gr H4350 GM210M

 

[justgoto]

I actually tried this yesterday with the same two powder charges, but used GM210M primers instead of GM215M. Here are the targets & velocities....what do you think?

65.0 gr H4350 GM210M

View attachment 34833


66.5 gr H4350 GM210M

View attachment 34834

If you switch any component at all, you'll need to start all over and preform a new ladder test. Once you switch a component, it changes the whole dynamic of the load.

I would not expect the load to get more precise by changing primers; that would be like guessing on a different powder charge, it may work, but probably not.

 

[live2huntmt]

If you switch any component at all, you'll need to start all over and preform a new ladder test. Once you switch a component, it changes the whole dynamic of the load.

I would not expect the load to get more precise by changing primers; that would be like guessing on a different powder charge, it may work, but probably not.

I appreciate your input but would like to kindly disagree with you on this one.....I have on multiple occasions cut my ES in half by switching between Magnum & Standard primers.....WSM's can go either way. However, I did not see my ES cut in half this time.

 

[justgoto]

Sorry....I should have listed each shot's velocity during my Ladder Test...here they are:

300 WSM, GM215M, H4350 60.0-67.0, CBTO 2.250", COAL 2.880"

1) 60.0gr 2726 fps
2) 60.5gr 2754 fps
3) 61.0gr 2801 fps
4) 61.5gr 2818 fps
5) 62.0gr 2842 fps
6) 62.5gr 2861 fps
7) 63.0gr 2892 fps
8) 63.5gr 2936 fps
9) 64.0gr 2943 fps
10)64.5gr 2956 fps
11)65.0gr 2956 fps DUP 1
12)65.5gr 2989 fps
13)66.0gr 3016 fps
14)66.5gr 3009 fps
15)67.0gr 3058 fps

"The other target displays too extreme of a velocity spread. By recording the velocity of each shot during the ladder test, you might have been able to predict that"

- Can you please teach me how to predict that by the above data? Thanks!

When you develop a load you need to things to happen that makes for long range precision, the velocities to have a low extreme spread, and small group.

So would first look at the groups finding something with a minimum of height difference, and not too extreme of a width, (unless you had high winds,) and shots not on the outer edges of the entire ladder.

So the first two I see are 3 and 4; they are 1/4MOA apart; with a 17FPS difference, (the cartridge containing more powder at a faster velocity.)
I would consider that a node, but I would try a charge weight between those 2 shots.

One way I can eliminate shots from being a node, is by looking at similar velocities not grouping together. We can see that with shots 11 and 12. Shot 10 is the same velocity at shot 11, yet they are very far apart. So when you're near that velocity, you're in a vibration.

With this new information, I would venture to select the charge weight between 3 and 4, the charge weight between 5 and 6. If shot 7 and 8 are in the same hole, a charge weight between those 2 may produce a good load.

 

[justgoto]

I appreciate your input but would like to kindly disagree with you on this one.....I have on multiple occasions cut my ES in half by switching between Magnum & Standard primers.....WSM's can go either way. However, I did not see my ES cut in half this time.

Actually, we do agree. I find that I can guess pretty well on finding a charge weight that shoots great. I simply preform a ladder test because it is a sure thing, almost always finding a node within 7 shots.