Ladder interpretation, please

358Rooster

358Rooster

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Got out to do a bit more load testing a while ago and would like some insight from guys who know how to read this well.

Straight .284 loaded with Berger VLD's in the top picture, Sierra MK's in the bottom picture, both 168's, both burning H4831SC at a range of 52.0 to 56.5 grains in 1/2 grain increments. All shot at 264 yards, bipod, sh*tty rear bag. Ugly day with 20 km winds from 1:00 - 2:00, +2 degrees, and a whole raft of other excuses.


I think shots 6 through 9 show promise even though #8 is way out. I thought it felt good at the time but I guess I was dead wrong.


Again, with the SMK's, one odd dropped shot (#5....and #8 shouldn't be there either IMO). I don't really remember the call on this one though - but there it is.



Forecast for Wednesday shows 5 km winds, so I'll head out to test this range of charges again to see how the two results compare. Thanks for any input you guys will share.

Rooster
 
Agree, 6-9 look best, at this point you really want 3 shot groups for each powder wt, this will allow you to focus on the vertical for that load, without trying to decide if the flyer was you, or the load.

Also, different bullets will layer copper differently, ideally you should not switch bullets between tests unless you clean and re-foul the bbl with the new bullet

M
 
Guys. You really need to start stretching out further for accurate ladder test. Min of 500 yards.

6-7 maby? It's really to hard to tell.
 
Thanks guys, I plan on running the second set of the same charges on a more cooperative day (I loaded up two of each and decided to only shoot one per, on that crappy day). I think what I'll do when I get home again is load two or three between 54.0 and 56.5 (shots 5 thru 10 as pictured) in 0.3 grain increments. This way, I'll cover the full range of the suspected node in smaller steps to hopefully define it a bit better. This, of course, after I confirm the second round of the first test. I don't think I have a need to go much finer than that, do I? I don't compete - I just want to get to the other corner of the 1/4 section:D



roberti11 said:
Agree, 6-9 look best, at this point you really want 3 shot groups for each powder wt, this will allow you to focus on the vertical for that load, without trying to decide if the flyer was you, or the load.

Also, different bullets will layer copper differently, ideally you should not switch bullets between tests unless you clean and re-foul the bbl with the new bullet

M
Click to expand...

One thing I failed to do with the pictured tests was run a few warming shots prior to (apparent by shot 1, at least). I've long wondered about one brand/type of bullet affecting a different brand/type but have not read or heard any concern about this for quite some time. This barrel now has 45 rounds through it and when I started development (shots 3 through 13 of total), the difference between the first shot of the first test and the fifth shot was quite dramatic. Shot 1 was low left and shots 2 through 5 hits were POA elevation and slowly worked their way back to the right to then start a counter clockwise "revolving" cluster. I cleaned again it after that test lot (shot total 13) but have not touched it since. Each outing after that was the same; first round cold bore was low but windage was good. When I swithced to the SMK's after the VLD's in these latest tests, no corrections were made and POI's were pretty much the same at the distance. But you're right - I should at least remove that variable.

Thanks again,
Rooster
 
Tikka6xc said:
Guys. You really need to start stretching out further for accurate ladder test. Min of 500 yards.

6-7 maby? It's really to hard to tell.
Click to expand...

This has also been on my mind a lot since this last test. Much past 300 is a pain in the a$$ for me to keep track of 'per shot' impacts, as my spotting scope isn't the greatest and they're getting tough to see with my 6.5-20 Zeiss. I think I'll colour code the ogives, move back a ways and investigate the results when the lot is finished next time. Maybe a switch to plain white paper with a bright sticker dot would be better? I find impacts tough to see on gridded targets past 3-400.

Rooster
 
Make yourself a big shoot n see target. Bright colored paper ro cardboard, tape over it packing tape, then spray paint it black. I would think if you can see a bullet hole at 300 in white paper you should be able to see the shoot n see style target from a lot farther away.
 
Big sheet of white paper - Called banner paper. Works like a charm. black speck on white background is visible from a surprising distance.

Put your aiming point(s) above the banner and drop the bullets into the white sheet. should be easier to see hits that way... or just get a wireless camera set up.

300yds or there abouts is plenty far enough to start tuning.

Definitely start using 2 or 3 rds per load step cause you need to eliminate human error and prove consistency. See my tuning articles on my website in the TECH section. I gave up using 1 shot ladder testing a long time ago.

And I would move quickly to smaller steps once you identify interesting nodes.

Good luck with your tuning.
Jerry
 
Thanks Jerry. Yes, I've read your article several times and this is essentially what I've modeled my tests from. I intended to shoot two full rounds of single shot ladders to find the basic nodes and account for human error but that day was just not conducive to real reliable results (at least at my competence level). I still intend to shoot that lot but will also take with me the next step in the process. As some others have identified (and I agree), charges around shots six through nine are what I'll be chasing but further reducing each charge to 0.3 grain increments, using the now fireformed brass.

I really need a different rear bag setup. Which of the Protektors that you offer do you recommend for use with a 6-9" bipod? Nobody in this area carries anything like that and I don't know anyone who owns one.

Thanks,
Rooster
 
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300 is still to clusterd. 500 is the closest you should do the test. At that range in .5gn inc your nodes really show up and you can pretty much guess what bullet was what..... However to make sure the way you do it is by colouring the bullets with a marker and keep track of what's what. The hole will have a red or green ext around it.

My old user name here was The AKD. I had posted pictures in the past of ladder test done with some range.
 
The biggest problem with distances beyond 300 is the affect of wind. Given that you have a single data point, a slight gust pushing a bullet this way or that can really have a dramatic affect on your interpretation of the results.

Even the affect of mirage can distort your results.

That is why I do not use a single bullet but I do track where each pair or triplet land and how that group forms.

Jerry
 
Travelling home this afternoon, shooting tomorrow. F'n forecast has changed now to +4 (from 14) with 10k (from 5) west winds, moving to south at 20 - I shoot straight east. Guess I better get out there early......and contend with the sun.

I'll stretch it out a bit. Just a bit hesitant about exaggerating things due to wind effect and operator error (as I'm sure the pictures dictate). Yes, several groups are in order. As I said, I don't compete and am not necessarily looking for the 'nth' degree. I don't want to play the benchrest game. I've been out to 800 on steel (different rifle) but was only looking for hits. I want this, only further out soon. If I can consistently hit steel at 1000, I'm a happy guy. How finite does one need to be with ammunition in order to do this? Seems a hit on an IPSC target requires 1-1.5 MOA out there. For me, I could likely load up a bunch anywhere between my test shots 6-9 and pound away and that would still shoot better than me. Time will tell...

What annoys the pizz out of me is reading about guys who get way out there with stock rifles and factory ammo or a load they just "threw together" and I struggle with a custom and top shelf components. I definitely don't get out as much as I'd like (have had the rifle since Sept 25 and have 45 rds thru) and that definitely factors. But I like to think that my loading OCD should compliment the results and also like to think I'm of high-average intuition. It's frustrating when it doesn't come out that way on paper.

I appreciate everything you guys have contributed and look forward to more if you have it. I'll post results from tomorrow's shoot.

Cheers!
Rooster
 
Don't fret. I'm fairly sure the the 'bone stock rifle shooting half MOA with federal blue box' guys are fudging a bit. You're just an honest shooter.

You probably take pictures of your fish beside a tape measure too!

See what I'm saying?
 
Mystic Precision said:
The biggest problem with distances beyond 300 is the affect of wind. Given that you have a single data point, a slight gust pushing a bullet this way or that can really have a dramatic affect on your interpretation of the results.

Even the affect of mirage can distort your results.

That is why I do not use a single bullet but I do track where each pair or triplet land and how that group forms.

Jerry
Click to expand...


Vertical spread is all your looking at in a ladder test. If the bullets are left or right from wind it does not matter.

Mirage @ 500 ..... are u serious ? Your thinking to much. Even my 6yr old nephew can shoot @ 500y with out even knowing mirage exsist.

The point of a ladder test is to quickly get you in the best node to develop an accurate load using minimal ammo. You can either do it right or keep loading testing groups all day to shoot at close range.
 
lol wow blackwater. I might quote that in my sig.

op. you can either take my advice or not. I am giving you the info I am from experience not what I think or have read.


- my nephew is actually in grade 5. However old that is was not the big point, the big point is that if mirage effects you that much @ 500y..... Either move off the lava ur on or accept long range is not for you.
 
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Alot of the mirage/wind and affect has to do with the terrain you shoot in. When I was competing in SK, the winds were huge but the vertical component was mild.

You dont get much vertical off a flat field even with a few cows around.

Where I normally shoot, getting 1 MOA of vertical from a gust is no problem at all. Wind swirls and you get all sorts of fun. But you learn that and adjust for it.

So I adapt my tuning to suit as many different conditions as I can. Vertical is a huge part of successful LR tuning and I feel my methods get them down to minimal levels.

There are so many ways to reach the same end goal that it really doesn't matter what you choose AS LONG AS IT PROVIDES CONSISTENT AND REPEATABLE RESULTS.

And mirage can affect your POA quite substantially even at 300m.

Try shooting on the Wet coast after a drizzle and the sun comes up. Affect of mirage on your ability to aim is massive.

Jerry
 
I've been hunting the same slough for over 25 years. When a stiff wind is coming down off the hill in my face and rolling down over the jack pines it definitely affects my shots vertically as opposed to a still day especially when lobbing 150's from a 270.

These days I use a 7mm mag and it's less of an issue.
 
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