Help with ladder test #'s

jmccracken1214

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Using H4350 and Sierra 110smk

Shot 10 rounds. Little puzzled by some of the higher charges having a lower velocity. Had to seat these long arse bullets 56thou off lands to fit in mags.

Any promising #'s here to start at?

IMG_20181014_101919.jpg
 
Shows nothing but velocities, no mention of accuracy.
Sometimes the fastest load isn't the most accurate. And as we all know ACCURACY is KING!!!
 
Shows nothing but velocities, no mention of accuracy.
Sometimes the fastest load isn't the most accurate. And as we all know ACCURACY is KING!!!

He's looking for flat spots in velocity where slight variations in charge weight don't result in much of a pressure change. It's a method for finding low SD/ES rounds which in theory should also produce an accurate load since consistency = accuracy.
 
He's looking for flat spots in velocity where slight variations in charge weight don't result in much of a pressure change. It's a method for finding low SD/ES rounds which in theory should also produce an accurate load since consistency = accuracy.
True true!
100 yard shooting, velocity doesn't matter so much but if I have a 50-75fps spread, I will not be getting accurate hits out to 1000 yards.

May try 40.8
 
He's looking for flat spots in velocity where slight variations in charge weight don't result in much of a pressure change. It's a method for finding low SD/ES rounds which in theory should also produce an accurate load since consistency = accuracy.

I think you're both missing the point. If it doesn't hit where you're aiming it's worthless, regardless of how fast it misses. And since you have no method of measuring pressure that theory is worthless as well. All you're doing is measuring velocity.
I have records and targets that have not so hot ES and SD but have phenomenal accuracy.
Always work toward accuracy first and then see how fast it can be pushed before the accuracy goes away.
 
I think your OAL is what’s throwing you off. Try loading 42gr at 2.900 coal and hand feeding. You may have to put some DBM on that stock and use AI mags


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I think your OAL is what’s throwing you off. Try loading 42gr at 2.900 coal and hand feeding. You may have to put some DBM on that stock and use AI mags


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I've got bottom metal and ai mags. But the Magpul mags dont allow as much space as the expensive accuracy mags.

I agree on length, I did not want to be that far off the lands, but this is what they look like in the mag.
IMG_20181014_094641.jpg
 
e7b0c22213ff3c1a28c39ff7b3125f9a.png



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I thought it said 2.27 in your notes


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That was to the ogive of the bullet, when touching my lands. I write that down so I know where to base my loads off of, if i want to do 5,10,15 off the lands, i subrtract from that. but case length, with bullet seated, tip to tip is 2.87 to fit in the mags.
 
I think you're both missing the point. If it doesn't hit where you're aiming it's worthless, regardless of how fast it misses. And since you have no method of measuring pressure that theory is worthless as well. All you're doing is measuring velocity.
I have records and targets that have not so hot ES and SD but have phenomenal accuracy.
Always work toward accuracy first and then see how fast it can be pushed before the accuracy goes away.
^^^what he said^^^
 
I've also had groups shoot great at 100, 1 hole and have bad Es and Sd.... But when you have a big velocity spread, you don't know what round is going what speed. Could be 50-75fps difference. I shoot long range. Not trying to print benchrest groups. If I have 1 round leave the barrel at 3000 fps, at 1000, and hold the same, the next one coming out faster or slower is going to be way off. High or low whichever speed it's coming out at.
That's why I do my tests this way. Lots of pro long range shooters do this.
 
I've also had groups shoot great at 100, 1 hole and have bad Es and Sd.... But when you have a big velocity spread, you don't know what round is going what speed. Could be 50-75fps difference. I shoot long range. Not trying to print benchrest groups. If I have 1 round leave the barrel at 3000 fps, at 1000, and hold the same, the next one coming out faster or slower is going to be way off. High or low whichever speed it's coming out at.
That's why I do my tests this way. Lots of pro long range shooters do this.

Someone told me to shoot for a target velocity (the happy zone where ES and SD may or may not be flat) and then fine tune seating depths and things like neck tension to fine tune accuracy.


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I'm not trying to be an ass but this is a good way to find consistent speeds and I have to know my ammo is consistent at long range.

Example, 3050fps for my round is 68 clicks at 1000 yards. If my next round is 3000fps, it's 71 clicks. At that distance, that's a 10.8" drop from the first round. And not knowing your speeds, that could mean a miss, depending on where you're holding, wind, size of target.
 
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I'm not trying to be an ass but this is a good way to find consistent speeds and I have to know my ammo is consistent at long range.

Example, 3050fps for my round is 68 clicks at 1000 yards. If my neck round is 3000fps, it's 71 clicks. At that distance, that's a 10.8" drop from the first round. And not knowing your speeds, that could mean a miss, depending on where you're holding, wind, size of target.

We are on the same page


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Shows nothing but velocities, no mention of accuracy.
Sometimes the fastest load isn't the most accurate. And as we all know ACCURACY is KING!!!
Very true, if you are shooting at 100 yards. Going out past 300 yards, a significant spread in velocity starts to show as vertical stringing. BUT, just because one finds a flat spot in velocity does not mean it will translate to accuracy at any distance, as the barrel harmonics may not line up with a velocity node.

The vast majority of my load testing occurs @100 yards, simply because that is what is available to me. I tried the ladder test once at 300 yards, and looking at either the vertical dispersion or the velocity numbers did not really tell me much (or I did not know how to interpret it). I believe a single shot at a given charge level is not statistically significant as one has no idea where that single shot would fall inside the extreme spread that might exist at that given charge. When I have shot 3 or 5 shot groups, then I start to see not only a flat spot (or two) in a given charge range, I also see where the extreme spread and standard deviation also decrease (usually in a velocity node). Hopefully, it will also be an accuracy node as well.
 
Have you always been an asshole, or is this a recent turn of events?? You seem to have a real boner on for me, you gay or something??
No sir. you're just extremely wrong on a lot of things I'm starting to see all at one time on the Forum I'm guessing you're an older guy and think you know everything. get on Google and search a little instead of being on the forum so much you might learn something
 
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I would have thought most on this forum would be open to learning and trying new things.. I used this method my first time doing load development, picked a charge base on velocity nodes and shot a ragged hole at 100 with great es/sd.. and didn't burn through a ton of bullets and powder doing it the traditional way of 5 rounds each charge.
 
I would have thought most on this forum would be open to learning and trying new things.. I used this method my first time doing load development, picked a charge base on velocity nodes and shot a ragged hole at 100 with great es/sd.. and didn't burn through a ton of bullets and powder doing it the traditional way of 5 rounds each charge.
Most are. Can't fix stupid though.
 
I spent a lot of time thinking on this subject- and over-analyzing it. As others have said, accuracy is key. Velocity nodes are a secondary effect. It's really weird when you're doing an OCW and the velocity goes down. Ladders in the traditional sense take a lot longer. Some pundits say it's the faster way to find where to start looking for accuracy, but since you get more than one, I disagree. The good news is that OCW doesn't require a chrono, but is fine to confirm that you get both and accuracy and velocity node.

There are many factors involved, but two are key- barrel harmonics and velocity. Velocity by itself is intriguing- how a higher load has a lower velocity is tough to figure out, but it's because of flame wave propagation, charge density, charge alignment, etc. Typically the most consistent load has a full charge. That does not mean it will be accurate.

Accuracy is a black art, and I'm still not sure how rounds like Federal Gold Match work so well in so many situations.

Nevertheless, the more interesting thing to chase is the harmonic. When you pull the trigger and it goes 'BANG', a shockwave travels to the end of the barrel faster than the round does. To be fair, for non-subs, the bullet builds up speed, and will be faster than sound as it gains velocity from the pressure but it starts at zero. And- sound in metal is faster than sound in air. And^2, the acceleration is not linear and depends on a lot of factors. But, from that 'BANG' the shockwave goes to the end of the barrel, vibrates your muzzle and returns back to the receiver, reflects back and goes down the muzzle again, rinse repeat. The end of the barrel is still when just as you pull the trigger (keep your caffeine down), but will vibrate several times as the shockwave goes down and back, pausing in between cycles. The most consistency is when the muzzle is still, so the goal is to find a velocity that the bullet exits when it is still. Look at Blake's groups above- they grow (vibrate) and contract between different charges. Nirvana is when you get both a non-vibrate and a consistent velocity for the best accuracy.
 
Yes, accuracy is the ultimate goal, but it must be accurate at the farthest distance you intend to shoot. At 100 yards, velocity differences don't matter much. At 1000 yards, it absolutely does matter. It is my opinion that accuracy at 100 yards doesn't mean squat if you intend to shoot at 1000 yards and you have large extreme spreads in velocity.

@Sas quatch , I also have a hard time understanding why the velocity is not always linear with the powder charge. And I also wonder about velocity nodes and how the extreme spread will vary with charge as well. Several times I have seen standard deviations drop to single digits around a velocity node, but open up to as much as 30fps between velocity nodes. Same powder, same bullet, same brass, same reloading session - only the charge level varies.

This is why I quit doing the "10 shot" ladder tests and went back to a pseudo OCW method. When there can be a 20-30 fps standard deviation, you can't put much faith in a velocity number from a single shot. Five, or even three, shots per charge tell me lot more about what is going on. Just my opinion.

I don't have any problems with anyone doing what works for them. If someone only shoots 100, or 300 yards, and they do their accuracy testing at those distances, then who needs a chrono - the accuracy they see on the target is the only thing that really matters. Shoot at varying distances, then everything changes. Different goals for different people.
 
Shoot a different bullet that gets you closer to the lands at mag length. Or buy the roomier mags. You’re just trying to force something here.

In my experience, monster jumps like .056 will not yield consistency.
 
Ran across a great video and excellent video on the difference between Optimum Charge Weight (OCW) ladder testing and the Satterlee "mini ladder" test. This is in the context of an experiment on the benefits of neck turning premium brass, but the demonstration of how the Satterlee method compares to the OCW method using actual group sizes and chronograph data is pretty compelling.

I will have to add this guy to my watch list.

The 6.5 guys spreadsheet is a great tool also.

Link to the video is below:

https://thereloadersnetwork.com/201...rass-improving-load-development-and-analysis/
 
Update.
Took the bergara 6.5 and the Ruger Precision 6mm out for ladder test's yesterday. Here's what I came up with. It was very cold yesterday morning and I guess that messed with speeds a bit, as it warmed up, my speeds increased with both calibers.

Ruger:
41.2 -2935
41.4 -2947
41.6 -2951
41.7 -2953
42. -2993

Loaded up 10 rounds at 41.6, shot 2 groups of 5. Average speed was 2988 (warmer weather) SD: 5 ES: 16 over 10 shots. Both grouped .50-.51.
15 shots total and I have a .5" grouping load with very consistent #'s out of a barrel with less than 80 rounds down it.

Bergara:
41 -2625
41.2 -2631
41.4 -2645
41.6 -2659
41.8 -2659
42 -2680

Loaded up 15 rounds at 41.7, lucked up and of 15 rounds, Avg Velocity : 2640 SD: 5 ES: 15

Grouped 5 shots, best group was 0.283" measuring center to center of impact. Worst group was 0.4745"

21 rounds fired. Found a load it likes, slower than I would have liked, but Im not messing with this level of accuracy or consistency.

H4350 used for both rifles.
Federal LR Match primers (bergara)
CCI small magnum primers (ruger)
108 ELDM 2.800 (ruger)
140ELDM 2.850 (bergara)

This is a good example of how this load work up should pan out. It doesnt always come this easy, but almost everytime, its faster and uses less ammo than loading up 5 rounds at each charge and testing. I fired 36 rounds total between 2 different platforms and came out with smoking loads for both. Can't beat that! Saved a buttload of time, and money on powder, bullets, primers.
 
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