Tag Archives: load work up

RELOADERS CORNER: Incremental Load Work-Up

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To get the most from your load testing, in the shortest time possible, learn the “Audette Method,” and put it work for you. Here’s how!

sight in target
Use a target that’s, one, easy to line up on, and, two, lets you make notes on the target itself. I usually circle and note the 3-shot increments, or you can add a number by each shot hole to indicate which try they belong to. Midsouth has some HERE

Glen Zediker

Last edition I suggested taking the step toward putting together a “portable” loading setup to allow for load development right at the range. This time I’ll talk about an idea on getting the most out of a test session in the quickest and surest way.

I have followed an “incremental” load work-up method for many years, and it’s served me well. Some call it the “Audette Method” named for the late and great Creighton Audette, long-time long-range and Benchrest experimenter.

Backing up a bit: Being able to employ this method efficiently requires having spent the preparation time, doing your homework, to know exactly how much “one click” is worth on your meter. Whether the meter clicks or not, it’s the value of one incremental mark on the metering arm. The value of that click or mark varies with the propellant, but by weighing several examples of each one-stop variation (done over at least a half-dozen stops) you’ll be able to accurately increase the charge for each test a known amount.

harrell's meter mounted
I count on a Harrell’s Precision meter. Its Culver mechanism allows for easy and accurate incremental adjustments in working up a load. The dryer sheet eliminates static electricity.

I usually test at 300 yards. That distance is adequate to give a good evaluation of accuracy and, for the purposes of this test, is also “far enough” that vertical spreads are more pronounced. Testing at 100 yards, sometimes they all look like good groups… So it’s at about 300 yards where we’ll start to see more difference in good and bad.

Get to the range and get set up, chronograph in place. Put up a target. Use whatever gives you a clear aiming point, but it’s helpful to have a light background not only to see the holes easier using a scope, but also to make notes on. More about that in a minute.

Use the same target for the entire session. (Put pasters over the previous holes if you want, but don’t change paper.) The reason for using the same target for the whole session is that helps determine vertical consistency as you work up through successively stouter propellant charges.

I fire 3 rounds per increment. As it gets closer to “done,” I increase it to 5 or 6. At that point I’ve hit a couple of speed points, two or three increments that represent a performance level I can live with (one is on the “iffy” end of the pressure, and I rarely choose that one) and am focusing more closely on group size. Final confirmation comes with one 20-round group. For what it’s worth, I usually pick the one in the middle.

A 3-round volley might seem inadequate, but it’s not if there’s confidence that the rounds are being well-directed and speed is being monitored. If I’m seeing more than 12-15 fps velocity spreads over 3 rounds, I’m not going to continue with that propellant. Same with group size: if it’s a big group over 3 rounds, it’s going to be a bigger group later on.

I’m sho no mathematician-statistician, but from experience I’ve found that, while certainly there’s some probability that the first 3 rounds fired might represent the extreme edges of the load’s group potential, and that all the others are going to land inside them, uhh, that’s not even a little bit likely. If it starts bad it finishes bad. On the contrary: no, just because the first 3 shots are close together and the velocity spread is low doesn’t mean it’s not going to get worse. Groups normally get bigger and velocities get wider, but, we have to start somewhere. It’s a matter of degrees. Also, the quality (accuracy) of the meter factors, and the better it is the better you can judge performance over fewer examples. And this is new brass, so that’s going to minimize inconsistencies further.

I can also tell you that it’s possible to wear out a barrel testing. No kidding.

Back to the “incremental” part of this test: As you increase the charges, bullets impact higher and higher on the target paper. You’re looking for a point where both group sizes and impact levels are very close together. If the groups are small, you won! That’s what Crieghton called a “sweet-spot” load, and that was one that didn’t show much on-target variance over a 2-3 increment charge difference (which is going to be about a half-grain of propellant). The value of such a load is immense, especially to a competitive shooter. It means that the daily variations, especially temperature, and even the small variances in propellant charges that might come with some propellants through meters, won’t affect your score. It’s also valuable to a hunter who’s planning to travel.

audette method loading
Audette Method: If it would only always work this way… This actually did work as shown so I captured and recreated it for posterity. The numbers on the left represent approximate propellant charge weights and the lines each indicate one click on my Harrell’s powder meter, a value about 0.15 grains of the propellant used in this test. Going up two clicks at a time for eight tries took me from 24.0 grains to about 26.0, which is a good range from a reasonable starting charge to pressure symptoms. I didn’t add in the velocities since that’s inconsequential to this illustration, but will say that “8” was too much and I settled on “6.” To make more sense out of this illustration, that ended up being 25.5 grains — step 6. I also went up using three rounds and skipping ahead by adding more clicks to the meter after viewing the (low) speeds on the first three groups (that’s why there’s no number 4 step; I went from step 3 to step 5). This has a lot to do with intuition sometimes. Point is, and should be, that here’s how the “Audette Method” is supposed to work: impact elevation on target goes up (these were fired at 300 yards) with charge increases, groups get smaller (hovering around two inches for this test) and stay small, and then elevation begins to stabilize. Choose a load that’s within this range. Then it’s a “sweet-spot” load. If this happens in your test, ask for no more!

That was the whole point to following this process. First, and foremost, it’s to find a good-performing load. It’s also how you find out if the propellant you chose is going to produce predictably. I can also tell you that I have chosen a propellant and a load using it that wasn’t always the highest speed or even the smallest single group. It was chosen because it will shoot predictably all year long. I base everything on the worst group, biggest velocity spread, not the smallest and lowest. If that doesn’t make sense it will after a summer on a tournament tour. If the worst group my combination will shoot is x-ring, and the worst spread is under 10 fps, it’s not the ammo that will lose the match…

As said to start this series, I started loading at the range because I got tired of bringing home partial batches of loser loads. And, you guessed it, the partial boxes usually contained recipes that were too hot. The only way to salvage those was to pull the bullets. Tedious. Or they were too low, of course, and fit only for busting up dirt clods. Plus, I’m able to test different charges in the same conditions. It’s a small investment that’s a huge time-saver.

If you do invest in a portable setup, exploit potentials. The possibilities for other tests are wide open, seating depth experiments, for instance.

CHECK OUT MORE TARGETS AT MIDSOUTH HERE

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.

RELOADERS CORNER: 3 Helps For Easy Load Work-Ups

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Read this before you start the process of working up a load for your new rifle! It could save you huge amounts of time and money… Find out more!

Glen Zediker

Spring is around the corner. Well, if you walk way out into the street and squint really hard you can at least think you see it… Well it’s coming soon enough, at least, now’s a good time to get ready.

I never have been big on the personal value of published load data. The data I’m referring to is that from propellant and other component manufacturers, and also from articles done by independents. I think all such information, at most, provides a place to start, and it also gives some ideas on tendencies and cautions, and provides means for comparisons. But. I don’t think it can be taken straight to the loading bench with any guarantee of success, or of attaining “advertised” performance. And I say that not because I don’t think these folks don’t know what they’re doing. They do! It’s because, after way more than enough experience in proving myself right, I can tell you absolutely that their rifle is not your rifle! Neither, necessarily, are their propellant, primer, case, or bullet. Always take careful note of the barrel and components used for any published test data, and compare them to yours. In later comparisons of my notes with published data, sometimes I’m higher, often times I’m lower, and enough times I’m way lower… That’s the main concern there.

It’s not at all difficult to learn to develop your own loads, to essentially write your own loading manual.

To do this efficiently, you need to learn to load at the range. Right, right there near to where you’re testing. An unremarkable investment in a few tools and a little creativity can provide a way to take your show on the road.

Lee press mounted outdoors
You don’t have to invest a fortune to take your show on the road. A C-clamp and one of these little Lee Reloader presses is all you need! And a good powder meter. One with a clamp is handiest, or just mount it to a piece of wood and clamp that down (even a pickup tailgate works just fine). One clamp is adequate on the press since bullet seating is all in the “down” direction and not much force is needed.

The reason to do this is because it provides a way to precisely chart results. It’s a more reliable and accurate way to proceed. Otherwise, the option is to load varying charges at home and then see what happens at the range. That’s okay, but not nearly as good as on-the-spot experiements. Plus, you won’t have left over partial boxes of poor-performing rounds. It’s more economical and way on more efficient.

The preparation part, and this is what you might spend the remaining cold month or two working on, is, first, to get the tooling ready and, second, and most important, to start making notes on your powder meter.

Important: To be able to work up at the range, it’s mandatory that you’re using a meter that has incremental adjustment. Either a “click”-type “Culver”-style insert or, at minimum, a micrometer-style metering arm. You’ll be relying on the meter, not scales, to progress upward in propellant charges, and you absolutely have to know what the values are for each increment using the different propellants you plan to test. That is where you’ll be spending time prior to doing your homework. It’s well worth it! It can be a nightmare trying to get scales to read accurately outdoors, including the digital type.

Harrells meter mounted outdoors
I map out the incremental values of each click on my Harrell’s meter adjustment drum with the propellant I’ll be testing, and it’s really easy to step up each trial with confidence. I carry the whole kit in a large tool box.
Harrells meter close up
This is a Culver insert. It’s a huge help in following this process. It’s precise and repeatable.

Equipment List and Set-Up
When I need to do load work, I size, prep, and prime new cases and put them in a cartridge carrier (usually a 100-round box). I then pack up my little press, seating die, my meter, some cleaning gear, C-clamps, and my propellants. The press and meter and cleaning gear go in a tool box. I usually carry the propellants in a picnic-type cooler. And, very importantly, my chronograph. A notebook, some masking tape, and a sack lunch… I might be there a while.

Always (always) use new cases for load work-up.

When I get to the range, I’ll clamp-mount my press and meter to a bench, get out all the rest, and set up the chronograph. Take a target downrange and tack it up. I test at 300 yards, unless the load is intended for shorter-range use. I initially test longer-range loads at 300. Maybe I’m lazy, but longer-range testing is a tad amount more tedious. I’ll come back for that after I have a contender or two.

Working Up The Load:
The reason it’s a “work-up” is clear enough: we’re almost always looking to get the highest velocity we can, safely. High velocity, or higher velocity, is usually all-good. Shorter flight time means less bullet drift and drop, and a harder hit.

So working up means increasing propellant charge until we’re happy: happy with the speed and also that the cases will still hold water. (And more about that next time…)

blown primer
Keep track of the cases in the order they were fired. This helps later on when the effects can be measured. This little outing here, though, didn’t require a gage to cipher: a tad amount hot on that last little go around (last case bottom row on the right). Thing is, I didn’t load a whole boxfull of those chamber bombs to take with me, and that’s the beauty of loading right at the range.

Very important: it is vitally necessary to have established a goal, a stopping point, prior to testing. That is one of the functions of published data. That goal is bound to be velocity, not charge weight. And that, right there, is why you’re working up at the range: you want to get “advertised” velocity and need to find the charge weight that produces it.

I work up 0.20 grains at a time. Sometimes it’s more if I’m reading an unuseably low velocity on the initial trial. Since my meter has a “Culver”-style insert, which I trust completely, I reference its number of clicks in my notes rather than the grain-weights (a Culver works like a sight knob, and reads in the number of clicks, not the weight itself). I check the weights when I get back, and I do that by clicking to the settings I found delivered, and then weighing the resultant charges. Otherwise, just throw a charge into a case and cap it with masking tape (clearly labeled).

It’s not necessary to fire many rounds per increment. “Mathematically” 3-5 rounds is a stable enough base to reckon the performance of one step. Of course, I’ll be shooting more successive proofs-per-trial once I get it close. Some folks, and especially competitive shooters, wear out a barrel testing loads. That’s not necessary.

Here are 3 things I’ve found over the years to better ensure reliable results. Learned, of course, the hard way.

1. Limit testing to no more than one variable. I test one propellant at a time, per trip. If you want to test more than one on one day, bring the bore cleaning kit and use it between propellant changes. Results are corrupt if you’re “mixing” residues. Same goes for bullets. Otherwise, though, don’t clean the barrel during the test. I fire my most important rounds after 60+ rounds have gone through it, so I want a realistic evaluation of accuracy and velocity.

2. Replace the cases back into the container in the order they were fired. This allows for accurate post-test measurements. Use masking tape and staggered rows to label and identify the steps. I use 100-round ammo boxes because they leave enough space for the tape strips.

3. Go up 0.20 grains but come off 0.50 grains! If a load EVER shows a pressure sign, even just one round, come off 0.50 grains, not 0.10 or 0.20. Believe me on this one…

Check out chronographs HERE
Take a look at suitable meters HERE

The information in this article is from Glen’s newest book, Top-Grade Ammo, available HERE at Midsouth. Also check HERE for more information about this and other publications from Zediker Publishing.