Ladder test fail. Stop telling newbs to use advanced techniques.

Discussion in 'Reloading' started by entoptics, Oct 29, 2018.

  1. entoptics

    entoptics Well-Known Member

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    This is gonna be long, so be warned.

    I recently posted an opinion on load development (because the OP asked for opinions), and got a pretty healthy dose of "that's simply not true" responses. The OP had a 300 WM, some 215 Bergers, and a custom rifle. He was getting 1.5 MOA groups. His posts indicated he was not a salty dog of reloading, though I could be wrong.

    I suggested that if it's shooting 1.5 MOA from a custom gun, then it's likely an exercise in futility to chase 3/4 MOA, and his problem may have been bullet selection (and gently mentioned overall loading technique). I advised that he first "find something that works OK", before spending resources on forcing a square peg into a round hole.

    The couple of posters who claimed I didn't know what I was talking about effectively stated that any powder/bullet combo could be made to shoot with proper tweaking of powder/OAL.

    Anyway, I decided do a test today, to see if I was actually out of my mind, and my thousands of rounds downrange had lied to me.

    This is a ladder test I did, to see if I could find a load to redeem a so far 3 MOA bullet (145 ELDX) in my Marlin X7 270 Win. Before you consider these results, it is important to note that only I spent a hundred rounds of load development on it when it was still my dad's. Almost immediately, after trying ~10 rounds of 5 different bullets, I found that it liked 140 NABs. Currently, with about 60 gr of H1000, at 200-300 yds this rifle will shoot about 1.25 MOA "all day", and has tossed ≤0.75 MOA groups on quite a few occasions. It's a bone stock $300 rifle, with some mid-range glass on top (4-16 Vortex HST), so I consider it a "decent shooter".

    400 yds, H1000, 145 ELD-X, 59.7 - 61.5 gr in 0.2 gr increments. ~2930 fps to ~2990 fps.
    [​IMG]

    As you can see, the ladder test finally illuminated what was wrong. It's clear, that with a load that settles in at the "node", it will shoot some real nice groups. Oh wait...Yeah, shot two is entirely off the target, and shot 8 and 8B (fired same load again, as LabRadar wasn't armed) are 8" apart...

    Before you shout "Brass! Concentricity! OAL! Hold your mouth right!"...Runout <0.004, neck turned brass, weight sorted to ± 2 grains, trimmed to 2.530", and a previous OAL test showed no love, so I ran this ladder at 0.04 off the lands, cause I hadn't tried that one before.

    In summary, I'm no Broz, and never claimed to be, but if I can't "find the node", then perhaps it's a bad idea to tell folks that are relatively new to the game about all this voodoo. If the rifle is shooting 1MOA with a load, then sure, it's time to look at the minutiae, but if your $2000 custom rig is printing 1.5 MOA, then it's probably not seating depth or powder charge that's your problem.

    P.S. For giggles, my buddy also tried a ladder test today on his Savage LRH 300 WM, using 212 ELD-X and H1000, and actually did appear to find a "node". I can post pictures if anyone is interested, but he got 4 rounds into half MOA at 400 yds, with 0.8 gr charge weight spread. Thing is his rifle already was shooting the 212 ELDX into sub MOA reliably, with my reloads developed for my Shilen equipped Savage 300 LRH, so we figured "What the hell?", and are hoping to tune another 1/4 off for his gun.

    Point is. Ladder/OCW/OAL/etc isn't stupid, but IMO, it's for advanced users who already have their rifle at "~MOA" levels. Suggesting otherwise is likely an expensive waist of time for the average shooter/reloader.

    (Update: OP from other thread reported a half MOA group, after "all day" shooting a bunch of OAL/charge combos. Perhaps this refutes my post, or perhaps he learned his rifle, or it shoots better fouled, or luck, or ...). Just wanted to give full disclosure.
     
  2. Mikecr

    Mikecr Well-Known Member

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    For me a gun will shoot 1/2moa or better to 300yds -unless there is a problem with the shooting system, cartridge, or load.
    And load development itself is not slinging out random abstracts and settling on something like 1.5moa, because the gun is expected to do better no matter what, but hasn't yet.

    Hell I can make a true 1/4moa gun open to +1moa & back with Berger's full seating test. If I do this test while fire forming cases, and then run a powder ladder, then tweak best seating in it's window to shape grouping, I'll be close to 1/2moa grouping. Repeating for best bullet/primer/primer striking/tension will likely scoot me in solid 1/2moa grouping, and well under 1/2moa of accuracy. Further testing dials me even tighter, and with that being cold bore accuracy.

    Overall, this just takes a lot of effort. Add a poor build and cheap components and bad cartridge & bullet & powder choices, and expectations need to open with that. I just don't ever put myself in those places.
     
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  3. Barrelnut

    Barrelnut Well-Known Member

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    Also, could be he just finally figured out how to shoot the rifle....

    I've had a few times where a rifle just didn't seem to like a particular bullet. Last time was 178 Gr. ELDX in a 300 WSM. Shot the whole box and could reliably only get 1 ~ 1.5 MOA. This is in a rifle that shoots Bergers and Noslers very well...

    IMO, Nosler BT bullets will shoot well in about anything. If I'm having an issue trying to get something to shoot, I will often try Nosler BT's to see how they do.
     
  4. bob4

    bob4 Well-Known Member

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    It'll be interesting to see him post back if that 1/2 MOA is repeatable.
     
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  5. rfurman24

    rfurman24 Well-Known Member

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    Mikecr you pretty much nailed it but the OP is suggesting that seating depth testing after seeing a 1moa plus load is a waste which is completely false. Obviously I can not make others do seating depth testing nor do I really care but the reality is it matters so stop telling people it does not. Have you considered why Berger suggest their seating depth testing? As far as a ladder test being advanced that is wrong as well. A ladder is the easiest to read of any testing you can do. No one has ever said that every single powder/bullet/seating depth/rifle combination will give .25 moa. Entoptics I do agree with some of your post but could not disagree more with you telling someone seating depth testing was a waste of time. I even showed several seating depth test pics. Every single one of the 50ish loads I have developed have required seating depth testing and as stated in the other thread, just as Mikecr stated, seating depth can take a .25moa load to well over moa. I have found that certain cartridges are easier to tune such as the 204R, 20VT, 6.5 Creedmoor so the change in powder and or seating depth was not such a huge swing but I just have not seen that with larger overbore cartridges.

    "but if your $2000 custom rig is printing 1.5 MOA, then it's probably not seating depth or powder charge that's your problem."

    I showed you pics of this being completely false yet you came and started another topic to lead new guys astray. Do you want more pics of load development? I have $4k rifles that shoot over 2 moa at the incorrect seating depth and powder charge and .25 at the correct powder charge and seating depth. I can not for the life of me understand why you would spend that kind of money on a rifle and not do proper load develpment and if you are ok with 1moa then why would you not just but a cheap rifle? Most rifles are easily capable of 1moa these days.
     
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  6. Tyler Kee

    Tyler Kee Active Member

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    I've always felt that Berger's seating depth test is sort of a mandatory starting point for load development in a precision rifle. Barring that, working off whatever the bullet manufacturer suggests with the help of an OAL gauge. ex: Barnes says .050" off the lands.

    From there, I always load up a dozen or more rounds at different charge weights (.2 or .3 gr increments depending on case volume) and run it over the chrono until I start seeing signs of pressure on the primer. This gives me a good little graph in Excel so I can look for flat spots in the velocity curve, a decent amount of fireformed brass, and the upper boundary I can work within.

    From there, it's ---- or get off the pot time. Did I get the velocity i was looking for? Is there a big flat spot in velocity over the span of a grain or so? Did the Berger test show me that seating depth doesn't matter? Or that it matters a lot? If it all looks good, I'll load up 10 rounds in the middle of that velocity node and then go shoot it for groups (preferably 250+ yards) and velocity.

    Wam. Done.
     
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  7. Alex Wheeler

    Alex Wheeler Well-Known Member

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    Ladder tests are not necessarily advanced but they only work with accurate rifles. You also have to be willing to swap components. From your 10 shot ladder I can tell you, the rifle is not very accurate and does not like the bullet or powder your feeding it. 10 rounds to eliminate a component is not bad. And eliminating a component is the biggest hurdle out there when struggling with tuning. Most of the time your feeding it the wrong stuff. JMO
     
  8. Slickrick0999

    Slickrick0999 Member

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    I saw that you were using a labradar.
    Could you post the velocities of each round and powder charge?
    Just something got me interested in seeing.
    Thanks,
    Rick
     
  9. entoptics

    entoptics Well-Known Member

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    All of the following tests used reloads with hand weighed charges and weight sorted, neck turned, trimmed, etc., brass.

    270 Win test shown in the target picture in the OP. EDIT: The graph label is WRONG. This was a 145 ELDX.
    270 Chrg Wt Ladder.jpg

    The following graphs are for my 300 WM, Savage LRH, Shilen 24" heavy sporter. All groups were prone, bipod, rear bags, calm winds. 100-400 yds, majority at 200 yds. The average group size for this rifle, from ~50 measured groups is about 0.9 MOA, but that includes all testing, so there's some real stinkers in the mix (it hates all NABLRs). With the ELDM, 80% of the groups are ≤0.8 MOA.

    Ladder tests for charge/velocity. Find the nodes! (Interesting side lesson for newbs, even bullets of similar weight/construction, can produce quite different velocities and pressures!)
    300 Chrg Wt Ladder.jpg

    OAL vs MOA. Solid symbols are entire 4 shot groups, open symbols have the worst flier subtracted to evaluate the influence of a loose nut on the trigger. Find the node!
    300WM Seating.jpg

    In my experience, with 8 or 10 reloading projects for $300 - $1500 off the shelf rifles, various forms of ladder tests and such haven't produced anything useful beyond picking a velocity I like.

    Regardless, I recently decided to revisit it for curiosity sake, and since I love shooting and collecting/analyzing data. I've tested my Shilen equipped, and my buddy's bone stock Savage LRH 300 WMs (consistent sub MOA shooters), two heavy barreled AR15s (~MOA shooters) as well as the aforementioned Marlin 270 (~1.5 MOA shooter). So far I have found no "nodes" in length or charge that shoot better than the recipes I settled on in the first place.

    I'm sure it works for some folks/guns. I'm also fairly certain there's some reports of "nodes" out there that are likely just bad statistics. As you can see in the graph below (essentially the "Berger Test"), I got the absolute OPPOSITE results on two different days. If I'd seen either of those day's results alone, I'd be convinced I'd found something real.

    OAL vs Group for two sessions. My rifle loves a good long jump...No wait...It likes them near the lands...
    300WM Conflicting Results.jpg

    In summary, I'm not saying it doesn't work. I'm saying that for the new reloader, and this particular experienced loader, it may not be all that useful.
     
    Last edited: Dec 16, 2018
  10. entoptics

    entoptics Well-Known Member

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    You are correct on the rifle not being that accurate. It's a $350 Marlin X7 that was essentially given to me. The test above is with the bullet/powder it likes the best EDIT: Wasn't paying attention, the OP test was with the ELDX, which it hates END EDIT: out of half dozen I tried in it (at the time, my dad was paying for the components, so I went hog wild with it and probably sent 20 different recipes down range). It shoots the 145 ELDX into a bench rest winning 3 MOA...

    It's about 1.5 MOA with stuff it "likes", and my favorite recipe will keep them between 0.8 and 1.25 MOA 80% of the time, which is good enough for it's purpose as a "free to me" backup elk/deer gun for ≤400 yds.

    I only revisited it recently, because I let my buddy, a new hunter, use my Savage for this hunting season to give him the best chance of success. I tried to use my best techniques to wring a little more out of it, but didn't get much. Hence this thread...
     
    Last edited: Dec 14, 2018
  11. Slickrick0999

    Slickrick0999 Member

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    Thanks! I'm new to looking at reloading like this. I mess around loading for my 308 but have played with it for years.
    I am about to have to develop a load for a new 300rum. I would like to minimize the rounds fired as much as possible if course. Thank you for the data, very impressive.
    I think I may run the deal with my 308 (everything else I've done returns my original load) before I try the Rum.
    Again, very interesting and I appreciate it!
     
  12. dok7mm

    dok7mm Well-Known Member

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    I have a great deal of confidence in using ladder tests, along with LabRadar velocities. It's a good way to find potential nodes. But it is also a useful tool to see things that don't work, be it seating depth, neck tension, powder/bullet combo, bedding, scope issues and lots more.

    I think seating depth is the key to improving good groups to great groups. When our brass prep is exacting, charge weight is consistent and bullets are sorted, tuning the seating depth decides how well that load shoots at long range. JMO
     
  13. oldfortyfiveauto

    oldfortyfiveauto Well-Known Member

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    Just to help making some sense of your ladder targets you might try doing a target like this. In this case I used 6 loads of three each. I find this much easier to see what is really going on. Note how much the loads shifted to the left as the charge was increased.

    Ladder.jpg
     
  14. Mikecr

    Mikecr Well-Known Member

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    Looks like you're just repeating a min-ladder, each with a POA change in the middle, and obviously too close.
    The best powder load there does not seem easier to see than a standard ladder.