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Thread: Flawed or not, will this work?

  1. #1
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    Default Flawed or not, will this work?

    Okay I want accuracy plus speed. I know faster does not always equate to better accuracy but I want a blend of both. Here is my game plan on developing some future hand loads. My goal is to achieve the best accuracy/speed combo without wasting a lot of components and since I have started reloading various calibers I am working up a collection of partial powder containers.

    Step 1: Load up one cartridge of each weight stepping up in .5 grain increments from min to max. Shoot each cartridge over the chronograph going from lightest charged to heaviest. Watching for pressure signs and monitoring speed. This step is basically to test the upper end of the charge scale and see if it is safe in my rifle and also to see the approximate fps gain for each half grain increment and see if the speed increase flattens at a given point.

    Step 2: Once complete with step one load up 3 cartridges each of the top 5 loads from above. Now shoot these for groups at 100 still using my chronograph. If one load shows promise then work around it in smaller increments and more shots per group (maybe 5). If not try a different powder that I have on hand known to work in the cartridge I am loading and repeat from step 1.

    Again my goal is to find a good accurate load with upper end velocity. I know sometimes slower is more accurate in certain combinations, but I feel with the right combination I should be able to get both or at least a good balance.

    Thinking out loud but thought this would be good food for the brain!

  2. #2
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    Your theory is sound but the dimensions are off center a bit.

    First, depending on the size of the case, the .5 grain increase may not be noticed. In a 223 or similar sized case it is the right amount but for a 30-06 or larger you'll need to use 1.0 grain increments.

    Secondly one shot doesn't prove anything and will at best be misleading.

    Load five of each charge weight in .5 or 1.0 grain increments and slowly shoot all five into a group through the chronograph. This way you will get some useful data and a good average velocity of the load. Then let the rifle cool and shoot five of the next increment of powder charge. Use only the same lot of brass bullet and primer and seat all at the same depth throughout the test.

    This is the technique I use and it generally takes 25 rounds, five groups of five shots, checking velocity all the way. Then the velocity gain per grain of powder will be obvious. Variations in velocity (Extreme spread) and ultimately Standard Deviation (SD) shows how consistant the load and how uniform the loading technique. We want low numbers here. Good SD is less than 10 fps, and this is still suspect with only five shots but will still show trends in velocity spread. The ES number should be no more than 25 or 30 fps for a good load. If we don't change the charge weight by enough the velocity gain will be less than the ES number and we don't see any difference and don't learn anything.

    After this 25 rounds it is now time to go to another powder without changing anything. I usually take three rifles and 25 rounds each to the range with the chronograph and alternate rifles to allow adequate cooling. This gets a lot of useful data in a short time.

    I like your approach. Accuracy is always important but in a hunting rifle it makes no sense to use only the most accurate bullet and disregard terminal performance. By the same token it makes no sense to buy a powerful magnum rifle and down load it some mild load just to get match accuracy that isn't needed.

    If you feel it necessary to test fire with only one shot just to see if things are kosher, that load in your rifle, that's fine but the chrony will only give you a close guess of velocity but will help assess the load. If your chrony says your velocity is over max you certainly should reduce and start over.

    The flat spot or knee of the curve can be quite subtle and often isn't very obvious at all, sometimes it is. It is a good indicator of the load and it is at maximum. If you shoot all 25 rounds, five of each charge weight, and see gain per grain of 64 fps, 72, fps, 58, fps, 52, fps and 34 fps (this was taken from my last actual shoot with a 376 Steyr size case and one grain increments, no signs of pressure) The maximum load is the last load before the velocity increase dropped to half the mean three. I'll save you the math but the first three gave an average of 65 fps increase, the drop to half (actually 34) is a maximum load.

    Now go back and find the most accurate load of the previous four, do not shoot the last load with the gain per grain of only 34 fps. I would guess the best load would be half way between the 72 fps change and the 58 fps change. In my case one was 64.0 grains (gave 72 fps over the 63.0 grains) the next increment was 65.0 grains, (gave 58 fps gain over the 64 grain load) I loaded 64.5 and got an SD of 4 fps and an ES of 16 for five shots. They all touched in the target at 100. This was with 350 grain Swift Aframe bullets at 2412 fps in a forty caliber (.411) rifle. It was time to quit. The powder was H4895, I do love that stuff.
    Is there nothing so sacred on this earth that you aren't willing to kill or die for?



  3. #3
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    That sounds OK.

    The only thing I would say, is that when you actually do it, it might not work out exactly like your plans.

    The velocity is a good way to determine if you have a max load.

    Smitty of the North
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
    You can't out-give God.

  4. #4

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    Quote Originally Posted by BigBlack View Post
    Okay I want accuracy plus speed. I know faster does not always equate to better accuracy but I want a blend of both. Here is my game plan on developing some future hand loads. My goal is to achieve the best accuracy/speed combo without wasting a lot of components and since I have started reloading various calibers I am working up a collection of partial powder containers.

    Step 1: Load up one cartridge of each weight stepping up in .5 grain increments from min to max. Shoot each cartridge over the chronograph going from lightest charged to heaviest. Watching for pressure signs and monitoring speed. This step is basically to test the upper end of the charge scale and see if it is safe in my rifle and also to see the approximate fps gain for each half grain increment and see if the speed increase flattens at a given point.

    Step 2: Once complete with step one load up 3 cartridges each of the top 5 loads from above. Now shoot these for groups at 100 still using my chronograph. If one load shows promise then work around it in smaller increments and more shots per group (maybe 5). If not try a different powder that I have on hand known to work in the cartridge I am loading and repeat from step 1.

    Again my goal is to find a good accurate load with upper end velocity. I know sometimes slower is more accurate in certain combinations, but I feel with the right combination I should be able to get both or at least a good balance.

    Thinking out loud but thought this would be good food for the brain!
    This is basically my approach, except I load 2 of each step up, and at the lower end I step up 1 gr at a time, and near the upper end I step up a half gr each step.

  5. #5
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    when loading hunting cartridges, generally it is a waste of time and resourses to begin at starting loads. i usually start 1 gr under max and crono from there. if the chrono shows consistant shot to shot numbers, accuracy will be consistant also.

    be sure to log your results.....or label cartridge boxes with your load data, then pick your favorites.

    *note/ there are many different combinations available that will be from satisfactory to excellent. use caution when assembling cartridges from components not listed in your manual as it may spike pressures.

    most of my testing is at temps of 60degrees or lower, this gives a better "pressure curve" consistant with cool-cold weather hunting. you may be amazed to know rounds tested in the heat will crono slower in the cold!

    happy trails
    jh

  6. #6

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    Another way:

    see http://www.desertsharpshooters.com/m...incredload.pdf
    or read on, looks interesting.
    The Incremental Load Development Method
    There is a load development process I used more than l0 Years that can tell you quite
    a lot about a rifle and that kinds of components it likes and at what velocity levels it will
    shoot best. I first read about this method in an article by the late Creighton Audette
    entitled, "It Ain't Necessarily So". This article appeared in the NRA's National
    Championship Training Clinics Manual Series in the volume, High-Power Rifle
    Shooting, Volume III. I never saw this load development method mentioned anywhere
    else, although Creighton may have published something on it in Precision Shooting
    back before I became familiar with the Magazine.
    I once commented that some of these NRA manuals had been out of print, for indeed
    some of them had been. The NRA has informed the Precision Shooting editor that all
    three of the High-Power manuals are now back in print. These manuals contain a
    wealth of Information for High-Power shooters, not found anywhere else.
    I tried Creighton's method. It is simplicity itself and certainly seemed to work well
    enough to tell me which loads would give me the best accuracy in my rifles at
    reasonable velocities and pressures with a particular bullet.
    Creighton Audette's Incremental Load Development Method (or ILDM for short)
    essentially is: Choose a bullet, primer, powder and case brand. Once you have
    chosen these things, there are two numbers you need to choose to use this method: A
    starting load and a load increment. With that chosen, load 20 rounds, start with the
    starting load and increase the charge weight stepwise by the increment you chose for
    each subsequent round. Load only one round with each charge weight. Then, using
    the same aim point, fire all these rounds on one target and interpret the results. Here
    are the details.
    For medium case capacity cartridges such as the .308 Win. or .30-06 Sprg. Audette's
    standard increment was 0.3 grains. For small cases such as the .222 Rem, .223 Rem
    and the like, use 0.2 grains. For medium-large Cases such as the .30-338, 0.3 shall
    also do. For really large cases, so large that I don't know of anybody who is crazy
    enough to bench test them a lot, pick anything you like, 0.5 or even 1.0. It's your
    Shoulder.
    Your start load (charge weight) should be simply the maximum charge weight for that
    cartridge with that bullet minus a decrement, that is 20 times the increment. Example: If
    you choose an increment of 0.3grs., the decrement would be 6.0 (= 20 times 0.3). In
    this example the decrement would be 6 grains. Make sure your starting load is a safe
    load. If you use a really slow powder, such as 4350 or slower, do not go below the
    recommended minimum load for that powder to avoid the risk of secondary explosion.
    The secondary explosion effect occasionally occurs with light loads of slow powders,
    or partly empty cases. It does not happen every time, but is frequent enough and
    dangerous enough, that almost all load manuals now list minimum charge weights. For
    you safety, never charge a case with less than the minimum recommended charge for
    Page 2
    Incremental Load Development Method
    a specific powder.
    Next, load up a set of test rounds by loading only one round, that's right, only one
    round, with each charge weight. Start with the starting load and load one round. Then
    load the next round with 'starting load + Increment'. The next round would be starting
    load + increment + increment. The next, starting load + increment + increment +
    increment. You step up a Ladder. An example will make this clearer.
    Example: If the starting load were 40.0 grains of 4895 and your increment is 0.3 grain,
    You would load the 1
    st Round with 40.0 grs., the 2nd with 40.3, the 3rd with 40.6, the
    4
    th 40.9, the 5th 41.2, the 6th 41.5, and so on ... . Twenty incremental loads will take
    you the Ladder up from 40.0 to 45.7 grains in 0.3 grain steps. When loading it is
    important to keep track of which charge is in each case. An easy way to keep things
    orderly is with a fine tip marker, like a Sharpie, write the charge weight on each case
    just before charging the case. Approximate weights are not good enough; weigh each
    charge to a tenth Grain (1/10 gr.).
    Once you have 20 rounds loaded, store them in a shell box starting with the lowest
    charge weight incrementing to the highest charge weight. This way you know precisely
    what charge is in each particular shell. Marked cases are a good safe guard against
    confusion. Now starting with the lightest charge, shoot them in charge weight order. To
    learn the most information from your efforts, there are some precepts you should do
    prior to beginning the test. They are:
    Start with a clean barrel and shoot about 5 fouling rounds, loaded with the
    starting load before you begin the ladder test. Shooting the fouling shots achieve
    several benefits: (1.) Fowlers allows you to get on target and gives you a chance
    to move your group on the target to a desired aim point. (2.) Fowlers give you a
    chance to properly adjust the position of your Chronograph screens. (3.) Fowlers
    fowl the barrel properly with powder foul from the powder used for the
    incremental Ladder test. This last item is important: After firing with one powder
    and then changing to another powder, even though both powders were from the
    same manufacturer, all too often a barrel needs as many as 4 or 5 rounds to
    "settle down". I don't know whether changing primers, while using the same
    powder would have the same effect, but it might. To begin with a clean bore and
    then to foul it with group shots with the starting load results in a controlled test
    beginning.
    Starting with lightest charge round , shoot the ladder test rounds in increasing
    charge weight order. When you are approaching the maximum load level watch
    for signs of excessive pressure. If they appear, stop!
    If possible chronograph all shots. Velocities should monotonically increase, but
    an occasional Oddball shot may yield an off-order-velocity. Logging velocities
    helps you to interpret the target. The chronograph has occasionally helped me to
    determine the powder charge, when I shot a round out of order.
    This step is the key to the method: Shoot all rounds on the same target using the
    same aim point. Number the shots and shot holes to identify which shot caused
    4.
    3.
    2.
    1.

    Page 3
    Incremental Load Development Method
    which hole in the target. Make good notes. Always be sure to write down any
    pertinent data, such as the fact that you saw the crosshairs fade to the right, or
    down, or wherever for any particular shot. This information is needed to interpret
    the data.
    Shoot the test at a goodly distance, at least 200 yards, but 300 yards is better.
    Creighton advised in his article to use 300 Yards. The problem at 300 Yards is
    that it is very difficult to identify the shots by number on a target that is that far
    away, unless you have a superior spotting scope, and it is a very calm day with
    no mirage, or use an electronic target system. The Ladder test can work at only
    100 yards, but sometimes it is hard to discern what happens on the target. The
    first time I ever tried this method was at 100 yards with a new Obermeyer barrel
    that set 14 shots into a 1.25 Inch hole. That was kind of hard to interpret.
    A 300 Yard range with target pits and pit pulley is the best scenario. Pull the target after
    each shot and number each shot hole with a pencil on the target face, or put numbered
    white Pastem's over holes that are in the black. At 200 yards, the shot holes can
    usually be seen, but when a tight cluster occurs it is hard to identify which shot is
    which.
    At any distance on a pit-less range, you will have to resort to plot the shots by number
    on a target diagram. While you shoot have someone else watch the target through a
    spotting scope. Another good idea is to use Birchwood-Casey Shoot-N-C targets.
    An important guide to successfully learn from a ladder test, is to set up the rifle exactly
    the same way as you intend to use it later on. This means, if you intend to use the rifle
    with a scope sight, then shoot the test with a scope on the rifle. If you intend to shoot
    from a rest, or other support, use the same rest, the same way.
    If you are going to peep the target through iron sights (as in High-Power competition),
    then shoot the test with the iron sights you intend to use on the rifle.
    If you shoot a ladder test with a rifle configuration set differently than the intended use,
    the rifle's recoil and vibration characteristics will differ enough that the load may not be
    optimum. Shoot any ladder test with the rifle set up the way you are going to use it!
    Exactly!
    After you finished shooting the rounds, you will have two data collections, that when
    looked at together can tell you a lot about your rifle. They are: the data sheet listing the
    loads and their velocities and the target with the numbered shot holes, or the target
    together with a target diagram with shots numbered. The target with the numbered shot
    holes is the most important.
    To plot shots on a target diagram and to have the target itself to compare to the
    diagram is very useful. Usually this helps to correct the diagram and enables to
    number most holes in the target.
    Interpreting the Data
    5.
    Page 4
    Incremental Load Development Method
    I can hear the wheels turning in your minds out there. You all ask, "How in Hamburger
    Helper can this mess tell me anything. The answer is simple, but you need to know
    what to look for. While ignoring the chronograph results look first at the target. Are there
    any places on the target that produced a halfway decent group?
    As velocity increases the shot holes will usually pattern upwards on the paper. The
    lowest velocity shot will usually hit the target lowest. The highest velocity shot will
    usually hit the paper highest. In this upward ladder there will usually be clumps or
    groups of shots. These are the most important of all. Sometimes the groups will be
    round, other times the groups will be vertical. If the test was preformed in a windless
    environment and the holes scatter from left to right as well as up and down, it is
    probably time to try another powder or primer and/or check the bedding of the action in
    your rifle.
    However, with any powder and primer combination the following usually happens.
    Within the 20 bullet impact pattern on a target, five or six consecutive shot groups can
    be found. This is not random. The numbered shot holes will march up the paper then
    stop for a few shots in a group before jumping out of the group and then resuming their
    upward march.
    The key to interpreting the pattern are all numbered shot holes. You could shoot with
    all sorts mixed loads with different bullet weights, different powders and primers,
    different cartridge cases brands, etc., 20 shots at one target and probably get a few
    nice three or four shot groups and maybe even a small five or more shots group
    somewhere in the 20 hole pattern in the target, but that wouldn't mean anything. Even
    with all matched components and everything else done correctly with the ladder test, a
    small group would not mean anything, unless that group was made by consecutive
    shots in increasing weight charge order.
    We only look for small groups formed by consecutive shots. We call such groups
    "Sweet Spots". In a Sweet Spot, the fired Rifle "cares not " about the powder charge
    weight, as long as it remains in a certain range. The ladder test purpose is simply to
    pick a charge in the middle of the Sweet Spot group charge weight range. One benefit
    to find a load with this method is, a load, tolerant to minor powder charge weight
    variations. Even if your powder measure technique is not accurate, the Incremental
    Load Development Method (ILDM) with the ladder test will show a load to be accurate
    with thrown charges.
    The Ladder Test works because ...
    If you look at the reason the right way, it is simple. As the powder charge increases, the
    muzzle velocity also increases, but the time the bullet accelerates in the barrel (called
    barrel time) decreases. As powder charge and muzzle velocity increases, recoil also
    increases, whipping the barrel. I believe the recoil induced muzzle elevation interacts
    with barrel vibration and barrel time effects.

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