Thread: 440m ladder test

Howdy
Matey and I have been working on some 6.5cm/143eldx/2209 reloads.
This was shot at 445 meters-

Our next step is to bracket the loads of shots 3,4 and 5.
At what stage would you adjust your seating depth?

Um, I don't understand your target...

Were these all shot at the same point of aim, and the lines represent vertical climb ?

Originally Posted by ebf

Um, I don't understand your target...

Were these all shot at the same point of aim, and the lines represent vertical climb ?

Yes,but the lines just lead to where I wrote the charge and velocity.

riiiight, and why are you choosing 3,4,5 to focus on ?

also, what chrony did you use ?

single shots don't tell you much. how do you know you did not shank any of the shots and affect where the point of impact is ?

I guess I am asking if your primary focus for analyzing this is velocity or drop ?

if it is speed I would be focusing on 5,6,7,8

6 and 7 would be my pick I always do a ladder at 100 as you are mainly looking for a flat spot in vol.
If no pressure I would go higher my Creedmoor used to group best around 2770 with the 143 the 2 powders I used were the same the best groups were around the same speed.
For a ladder I load as you have and shoot at 100 sometimes I don't even shoot on a target I look for the flat spot or node and check for pressure then load 5 of each 3 loads around that flat spot then I'll shoot them on a 100 m target.


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Why would 3 be above 4 and 9 be above 10. I don’t think anything can be derived from this data?

Originally Posted by mimms2

I just assume he knows how to shoot.

I've learnt not to make that assumption for any shooter - even myself

Relying on point of impact or groups as an initial method of doing load development is flawed in my view. Shooters often gravitate to small groups, even if it does not make sense or is not supported by better data. VERY FEW people can consistently shoot to poa...

In my mind a good chrony (labradar or magnetospeed) is a much more repeatable method of finding nodes. Forget about shooting groups till you identify the middle of the node. Then mess with seating depth to change group size. Several years back I watched some of the best F-class shooters in the world do load development at the Belmont complex in Aus. They shot over high-end chronos. Aiming at a sandbank 25 yards away. No target ! Kinda tells you what they think was important...

Figure out where your most likely margin of error is, and avoid that for analyzing results.

How sure are you that your powder charges are consistent ? If you shoot 5 (or even better 10) shots over a high-end chrono, do you get low single digit SD ?

How sure are you that the velocity is accurate ? What chrono are you using and do you get repeatable results.

How sure are you that you can shoot to point of aim EVERY time ? See the 5x5 accuracy challenge thread...

Watched a video recently by Ryan Furman on Long Range Only about this type of load development (which I'm going to try) and his experience showed that the testing needs to be done at a minimum of 600m and preferably 800-1000m if you have a very accurate rifle. And 2 shots per charge weight.

You need to be this far away to get meaningful results and to be able to isolate vertical nodes properly

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shots four and five are close for velocity and that. you could try load 40.7, 40.9, and 41.1.(fill in the gaps) if its a real flat spot for velocity and vertical spread go with a charge in the middle.

Originally Posted by The Claw

Watched a video recently by Ryan Furman on Long Range Only about this type of load development (which I'm going to try) and his experience showed that the testing needs to be done at a minimum of 600m and preferably 800-1000m if you have a very accurate rifle. And 2 shots per charge weight.

You need to be this far away to get meaningful results and to be able to isolate vertical nodes properly

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I have read a fair bit Ryan has written and he is a clued up guy read alot of info he has put up about the 30 nosler. To test that far the conditions would have to be pretty perfect. Not saying it cant be done. I think 440yards has given a good indication there. two shots per charge is definatley idea though.

I would look at 41.3 but would also extend the ladder into the 42+ range so long as there are no high pressure signs.

Originally Posted by Tim Dicko

I have read a fair bit Ryan has written and he is a clued up guy read alot of info he has put up about the 30 nosler. To test that far the conditions would have to be pretty perfect. Not saying it cant be done. I think 440yards has given a good indication there. two shots per charge is definatley idea though.

He reckons the results are still accurate with some wind. As long as you accurately place your shots and call any pulled shots before you see the target. It's vertical nodes that you are looking for and can discount horizontal due to wind. He also doesn't use a chrony during this testing phase as he reckons tight vertical is more important than flat velocity nodes

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Originally Posted by The Claw

He reckons the results are still accurate with some wind. As long as you accurately place your shots and call any pulled shots before you see the target. It's vertical nodes that you are looking for and can discount horizontal due to wind. He also doesn't use a chrony during this testing phase as he reckons tight vertical is more important than flat velocity nodes

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Thats interesting. Its a combination of things It depends on your methodology. i remember watching a video Dave Tubb was saying he does a ladder load at 200 yards quite offen by the sounds of it. https://www.youtube.com/watch?v=qP4PBnX6cZ8 11minutes in.

If you discount shot no.1, 9 bullets from cartridges loaded with a 1.8 grain different charge weight went into 4.5”.
Bullets 3,4 and 5 went into 2.25”.I think thats good shooting at 440m from a factory B14.We are loading for accuracy not speed,its a hunter.
We will repeat the ladder with 6 from 40.6 to 41gn and report back.

So it shoots 1 MOA with a slight change in powder loads is all I can interpret from that. If saving powder and projectiles is the aim of the test
( and getting the job done in a short time frame ) Then it looks good. These new idea methods seem a bit odd to me, I cant see how one shot groups prove anything at all.
As you say the rifle is a hunter and it may never get better than this either. Although its pedigree should help with smaller groups.
IIRC most CM's shoot 2209 well with 41.5 Grains for 143's sorry 140's

I went through a whole bunch of OCW and other tests with mine only to find this out a short time later.