Howdy
Matey and I have been working on some 6.5cm/143eldx/2209 reloads.
This was shot at 445 meters-
Attachment 146673
Our next step is to bracket the loads of shots 3,4 and 5.
At what stage would you adjust your seating depth?
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Howdy
Matey and I have been working on some 6.5cm/143eldx/2209 reloads.
This was shot at 445 meters-
Attachment 146673
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 ?
Yes,but the lines just lead to where I wrote the charge and velocity.Quote:
Originally Posted by ebf
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?
I've learnt not to make that assumption for any shooter - even myself :DQuote:
Originally Posted by mimms2
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.
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.Quote:
Originally Posted by The Claw
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.
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 nodesQuote:
Originally Posted by Tim Dicko
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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.Quote:
Originally Posted by The Claw
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.
Group size is irrelevant for a ladder test, especially at that distance. There is no consistent speed increase or a flat spot to call a node. A ladder test is an advanced technic for good reloaders who uses the right procedures through brass prep to bullet seating. So if you are using mix brass not trimmed as the same batch. Loaded with pulled bullets. Then you are wasting time.
Ok, so you are pretty much focusing on "group size". Although as John pointed out above, groups of 1 kinda mean zip.Quote:
Originally Posted by marky123
I would suggest you look at the speeds. Assuming of course you have a reliable and repeatable chrony.
Shots 5,6,7,8 are all within single digit ES from each other. It looks like a likely node in this ladder. Having said that, I would much rather look at SDs for 5 shot groups, the more data you put in the better the quality of the info you get out...
If (and it is a big IF), that is a node, then I would look at choosing a load in the middle, and playing with different seating depths. Shoot at least groups of 5. Do it at 100m and make sure the wind is not affecting group size.
I shoot mine with 140s and use 41.5 of 2209,but I don't even get 2600fps.Quote:
Originally Posted by johnd
The first time we went out matey shot a 2" three shot group with Hornady Match ammo.
Quote:
Originally Posted by ebf
As far as I understand,a ladder test is the relationship between POI and velocity.If unsuitable powder charges are used then they are nowhere near their next or previous.If it is,then they are closer together,hence 3,4 and 5 are suitable charge weights in this instance.Further testing with those charge weights will prove or disprove that.Happy to be proved wrong.
https://www.6mmbr.com/laddertest.htm...%20of%20primer.Quote:
Originally Posted by marky123
SUMMARY: Repetitive, round-robin Ladder Testing with multiple charge weights can reliably identify those loads which deliver minimal vertical dispersion at long range. ... While the Ladder Test method is primarily used to divine optimal charge weight, it can also be used to find the best seating depth or brand of primer.
Yup, but you are shooting single loads. How can you be sure the vertical dispersion is due to the load and not due to your shooting.Quote:
Originally Posted by marky123
That is why I keep stressing 5 shot groups. If you can show me 5 shots of the same load, all on the same vertical plane, then I will be convinced.
The correlation between increasing load and increasing velocity is not completely linear.
The target you posted has vertical all over the place (some of the slower loads land higher etc), so it does not really show much. If you were shooting a whippy hunting barrel, that may have been due to harmonics causing the projectile to leave the muzzle at different points in the whip, but then you would struggle to shoot accurate groups at most time.
All things working well, you would expect to see poi climb as the charge weight increases. Where that climb becomes contracted for equal increases in charge, is likely to be a node. I am not seeing any of that on your target (based on poi)... I do however see a potential node if you look at the speeds.
2 questions:
1) what chrony are you using ?
2) rifle ? particularly barrel profile ? is it a noodle or something a bit more beefy like HMR ?
Assuming the chrony and the shooter (not me) were working correctly and the conditions were good (there was no readable wind) then the test shows less POI dispersion and velocity between some shots to others.Quote:
Originally Posted by ebf
You can reasonably presume that those charge weights are ‘good’ loads.We will then repeat the ladder test hopefully under the same conditions with a smaller variance of charge weights at the same distance.Hopefully some of those loads will be ‘good’.Then we will select a load and shoot groups with it to confirm.
If that works then we have found a ‘better’ load with 20 shots.
More charge weight is not linear with velocity,I haven’t said it is.
We will shoot some 3 or 5 shot groups but only when we have dialled in a ‘good’ load.
Fuckit , you can lead a horse to water... :D
Good luck to you.
My observation has been that most people who come on here asking about ladder tests already know the method they are intent on using, and will go on to interpret the data in the way to which they are predisposed, irrespective of the advice received. The recipe they end up with may or may not be better than any other, but they will be more comfortable with it than they would otherwise be, having received from the test results what they perceive to be validation of their choice.
Happy shooter. Not my rifle.
Hard to argue with that.
I might add that there are already a lot of opinions on ladder testing and load development in general on this site for anyone who cares to look these out.
https://i.ibb.co/NFn15s4/Screen-Shot349.jpg
Start shooting groups with (40.8) 41-41.6gr and see what groups best with the lowest ES at the same time. After that, play with jump to fine tune.
If I have read and measured your target correctly the group of shots all fall within 36 cm or 14 inches in old money vertically and with one exception 15 cm horizontal 6 inches, There is no indication of point of aim and I understand that for your purpose that's not important.
However you seem to have produced a group of just over 2 moa at a range that most people would be over the moon about, so I can't see how it proves anything. Chances are choosing one of your ladder loads and firing that number of rounds would produce a similar looking target.
Marty, there is no group !
They have produced a target where there are 10 individual shots, each at a different charge weight. Instead of seeing vertical climb for increasing loads, the poi is all over the place.
Several people have pointed this out, and also tried to steer the op in the direction of velocities as a higher quality metric, but he seems to insist on loads 3,4 and 5 being where it is at...
In the article link posted earlier, the author mentions "rung groups" for the ladder. So shooting 3 at each charge weight. That would show that the shooter is actually able to shoot accurately to a poa, especially if done in rotation as described...
https://r.tapatalk.com/shareLink/top...ink_source=app
Here's the video and corresponding thread I talked about earlier
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And further interesting information
https://r.tapatalk.com/shareLink/top...ink_source=app
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Thank you @ebf Group may have been the wrong word for a loose association of random holes.
My point is a similar number of shots of any one of those loads would likely have produced a similar distribution so impressive though it is it actually provides no useable data. Three shots of each load and you might be getting somewhere, 9 and you are pretty much on the money.
Interesting Marky, do you have a short..ish barrel. My Speed was 2700 for a 26 inch barrel. Verified with drops and data out to 600 yds for 1/2 MOA on a good day, but usually "blew" out to 1 1/2 with wind. Still maintained 1/2 MOA verticallyQuote:
Originally Posted by marky123
Dont take any of the critique, we have given, the wrong way we just obviously do things differently.
Interesting video @The Claw, tx for posting. He makes several really valuable points about choosing the middle of the node for extra security. Something I've seen time and again at Seddon. Typically at least one of the days during nationals week, it turns southerly and temps drop. Guys who are at the margins of nodes (the speed demons) suddenly find themselves with massive vertical issues.Quote:
Originally Posted by The Claw
The other comments I found interesting were his statements about horizontal dispersion at long range due to seating depth. Probably more of an issue with the VLD type projectiles.
It would be a cool exercise to run a blind comparison between a long range ladder and a short range chrony only type node hunt, and see if the results differ. I suspect they will be very similar.
My over-riding comment is that in order for ladder tests to be of value, the shooter better be shit-hot and able to shoot to very small margins of error :D
