Load development efficiency

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Warpiece

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Even if we weren't facing a component famine, being efficient with load development has a lot of benefits.

Saving components from unnecessary testing is easy money, and i don't really enjoy shooting over my chronograph, too focused on not hitting it to even care that I'm doing something I love. Then there's the time, planning the groups, making adjustments and verifying. Trying to keep everything organized properly from home, to range and back. Then interpreting the data becomes it's own little 3 ring circus that can lead to a whole lot of nothing useful.

There are lots of methods people use to get the most out of testing. Design of experiments is an incredible concept, testing multiple variables at the same time, wasting minimal resources and still getting good data. Sounds awesome on paper, but getting it to work isn't something I've seen happen very often.

What is your preferred way to develop a new load? What do you look for? Do you decide what you're trying to do first and see what it takes to get there, or do you go through a preset process and let the data tell you what you have to work with? How much data do you need before you're confident enough to start producing? 3 rounds each group, 10, 50 or more? How thorough are you? Do you test every tenth of a grain or skip half a grain or more between groups? Do you test different seating depths at the same time or is it a separate process, if you even do it.
 
Get a different chronograph which eliminates your risk of bullet strike.

5-10 rounds warm up and foul, 24 rounds (8x incremental weights in triplicate). Load development is done, well beyond the expectation of “famine phase load development.”
 
I start by figuring out what I want/expect, so I know what I am after before I start.

Then do the research to gather baselines for everything I am going to be testing.

Then gather up everything and start testing, might even take a press to where I am going to shoot.

I have worked up loads using 3 different bullets and 4 different powders, all to the same power factor, in under two hours. Once reached I loaded up enough rounds for later testing.

D3A592E8-6FEC-41C6-8D92-343084F64DD0.jpeg

If your load is not accurate enough to miss the window above a chronograph at 10 feet, it would be completely useless anyway.
 
Load development for pistol
1. Search and read old threads on THR. Will help decide step 3
2. Start with a normal for caliber weight, cheapest avail (probably cast coated). 158gr 38/357 . 240gr 44 . Etc
3. Start with a powder that gets 1000 fps or more out of a 4” barrel or longer with 5 grains or more powder.
4. Shoot over chronograph & resting groups at 25y. Good when velocity you want & 3” or less group.
5. Load up 1000 rounds and shoot off hand. No more shooting from a rest / bench. And shoot. And shoot.

Load development for rifle
1. Search and read old threads on THR. Will help decide step 3
2. Start with a normal for caliber weight, cheapest avail (probably cup / core). 55gr 223 . 150gr 308 . Etc
3. Start with a powder that fills case to about 90% (bottom of shoulder) for starting loads.
4. Shoot over chrono & resting groups at 100y. When StDev in teens & 1” groups you have your hunting load.
5. Load up 500 rounds and shoot. And shoot. When you have 40 rounds left, proceed to step 6.

6. For a better hunting load get better bullets. Same powder, make 1 change at a time. Partitions, Barnes, etc.
7. For better target shooting do more advanced testing like ladder testing with various powders, bullets.
 
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>There are lots of methods people use to get the most out of testing. Design of experiments is an incredible concept, testing multiple variables at the same time, wasting minimal resources and still getting good data.

DOE software, last I checked, ran about $2000 or $200/month.
First, don't take safety short cuts. Start at the start load. You may only fire a round or two to verify no issues, but at least do that much.
Next, are you after accuracy or power factor? I wouldn't chase the two at the same time. For me, accuracy is the name of the game and never had a real desire for a chronograph except as a toy.
The only time I know of where power factor/velocity is critical is where absolute accuracy is not critical (or for long range rifle where you need exterior ballistics knowledge).
So, you can simply fire a round at each powder increment, inspect cases for pressure signs, plot the data and calculate the linear regression (Excel and such will do this for you) and then you can hone in on the PF you want and do your large data sets right there (seems to me the general consensus is that you need at least 10 velocity readings to get a good handle on the average velocity).
If you want accuracy, leave the chronograph and concentrate on shooting over a mechanical rest (or Ransom Rest).
Sorry, but both accuracy testing and PF testing will require many rounds (10-20 rounds for velocity or maybe five 5-shot or three 15-shot groups, depending on what you think you need).
Finally, DOE does not give you the final answers, it simply points you to the most significant variables to concentrate on for further testing.
 
Google "modified Audette load ladder"

Shoot at 200 or 300 yards (prefer 300). Leave the chronograph at home. The holes tell the story.
 
>Powder charge and pressure do not follow a linear proportionality. This isn’t a real thing.

No, you plot velocity vs charge weight. This is almost always linear. Pressure only comes into being mentioned because you have to INSPECT your fired cases for any pressure signs.
 
Here is a pic of me testing a .45 Colt load. It's my usual chrono at 5 yards and target at 7 yards setup.
I started setting up the target to keep my rounds in the middle of the chrono to keep them consistent,
as well as keeping the chrono safer, but it turned out to be a good way to check accuracy potential while
working up and getting numbers. When it shoots well at 7 yards and the numbers are good as well, I
shoot it at longer distances to check it.
12 Shots of Load #51 - 6 PB & 6 PF Pic 1.jpg
 
I had to chang lots of powder in 6 Dasher, so I tweaked it recently. I did three shot groups with 32.1, 32.2, & 32.3 Grs
and liked what I saw, so I loaded up some more with 32.2, 32.3, & 32.4 Grs in Lapua cases, and tried some Alpha brass
for the first time, and loaded them with 32.2 & 32.3, since they were slightly heavier, shot 2 warm ups, then five shot groups.
6 Dasher Test Loads - New lot of RL-15 - Lapua & Alpha Brass - Numbers @ 30%.JPG 6 Dasher Test Loads - New lot of RL-15 - Plus 3 Alpha Cases - Target @ 29%.JPG

Primers looked great, extraction was as easy as with no case, nice. :)

This was just tweaking, to get there I shot three shots each on target for a wider range of powder charges to get there with the last
lot of powder, so after shooting that charge with the new lot of powder I knew where I needed to look.
 
noylj said:
>Powder charge and pressure do not follow a linear proportionality. This isn’t a real thing.

No, you plot velocity vs charge weight. This is almost always linear. Pressure only comes into being mentioned because you have to INSPECT your fired cases for any pressure signs.
Click to expand...
ill go out on a limb her and say that pressure is felt in bolt lift resistence as the charges increase the cases exhibit radial expansion to the chamber walls first then in CBTD so once I start feeling that heavy resistance or pressure then I don't go further. I may give a case a quick look but Inspecting cases is done at the shop. Im also pretty sure a chronograph is not required to develop quality ammunition but as posted are very informative tool
 
I look at my load data & take my lowest to my highest & divide the difference by 5. That gives me 5 steps to reload from min to max & I load 5 rounds each of those 5 loads. A little something a wise man told me (if you are scared of shooting your crono use it with a total overcast sky & take the top diffusers & wires off it works just as good.) Then you have an almost unlimited height distance from the crono, so you won't hit it.
As I shoot each round I inspect the case for signs of overpressure, if I find any signs I STOP shooting & check the rest of the rounds. Each 5 round group is shot at one target & the gun is cleaned between each 5 round group. This gives me the best pattern out of my guns. If I have two patterns that are close I do another load of .1gr of powder between those two loads to see if I can get better.
 
I didn't realize how long and boring this post was till I finished. Didn't mean to write a book

My own methods are constantly changing, I don't think I've settled on doing it the same way twice at any point. Lately, I usually start with the bullet, decide what it's purpose is intended to be and capable of. Fmj pistol is usually plinking/ blasting, hollow points usually loaded to replicate self defense ammo. While I don't hunt anything aside from paper or steel, I load rifle with the intention of it being suited to that purpose. I take measurements from bullets anytime I buy a new projectile and keep them in a spreadsheet. I'll use this to compare results from similar bullets and loads developed with them.

For powder, I look into how loud and flashy it is, Longshot and power pistol get the blasting role often. I narrow it to powders that show a good potential for getting the bullet to an appropriate velocity for it to reliably function for its intended purpose.

Next I collect as much load data as I can find, I compile it into a personal load development sheet. This sheet is also constantly changing, generally all relevant load data will be listed side by side, I'll choose a starting point roughly at the average of the minimums, while not exceeding the lowest max. Charges outside of the range of the intended purpose are kept to a minimum, as little as a single round per charge, they're nothing more than a safety check assuming velocity comes anywhere close to the data. The charge increments depend on the spread within that required velocity window from the compiled data. If 26.1 to 28.9 grains falls within that window, I'll probably go half grain increments, with another development cycle based on those results to further narrow down potential loads. If it's a half grain spread, I'll do every tenth of a grain. I use a fine tip sharpie to mark each case with its charge weight, powder type and oal. I have occasionally included weights for each component to allow for later verification of the completed cartridge, which can be satisfying, but really pointless. I'll also load different oal based on the available data as it best matches the bullet, keeping the max charge per oal from the source data. I measure the seating die adjustments with calipers from body base to stem apex at the desired increments. I'll measure bullets lengths, get an average from a dozen or so, then use a comparator based off that info to get what I think would be a more consistent oal measurement. I don't know if I'm actually getting more consistent seating between adjustments, but the measurement suggests it. Number of rounds per group tends to parallel number of groups, less groups means more shots per group, more groups get less rounds each. I'm usually a minimum of 50 shots, up to 150 that in hind sight, was overkill that didn't give any better results.

Brass prep, I might be better off not discussing it much, I seem to have an obsession with cleaning brass and general prep. Most of my brass has been cleaned and polished more times than its been shot, some many, many more times. I can't justify it, but I can't stop myself. Most of you would probably be disgusted with what even one of those cleanings entails. We'll leave it at that.

I sort brass by headstamp, but I still mix it, in a controlled way for load development (just pistol) . I try to run each charge in roughly each headstamp by percentage on hand (general estimation) if i have 40% fc, 40% Winchester, 10% blazer, then each charge gets a distribution the same. Yes, it has an impact on the data, but one that I consider a positive. I load around max often enough that I don't want to be surprised by pressure signs from the headstamp I didn't run in the load workup. I can rarely get matching components enough to justify a separate workup for each headstamp. I'm not accurate enough with pistol that it's going to hold me back from reaching perfection anyway, but it has helped me reconsider what I'm doing when things unexpectedly started looking concerning from one type of brass but not another on the same charge. If I'm loading something special I'll stick to one headstamp, but even then, it's after load development, not before.

My development sheet will list test groups and variables for that workup. I'll include some detailed measurements with blank fields for chronograph results, weather, range location, cycling notes, date and time, gun, unusual recoil and muzzle flash along with a few other things I keep changing or rarely fill out. The sheet will have the compiled source data as well. This usually gets folded up and stored in the ammo box with the test groups. After it gets filled out, it gets entered to a spread sheet in Google drive.

I'll skip describing range day, there's no real procedure as I am limited by other members behavior and range conditions that change minute to minute.

Even though I go into it with a general goal for what kind of load I'm going for, I still end up just looking at the results with a "this is what this combination can do, how can I use it?" mindset. Even if the data doesn't show what i wanted, it puts me in a position to find another combination that might work. Even something as simple as noting the minimum charge still cycles the action in that combination, or doesn't is a bit of a headstart for planning similar combinations in the future.

For pistol, I don't even bother with paper targets, steel is more than suitable. If I'm ringing the little steel plate in the face of the target while in the proper velocity range at 30 feet, I'm happy with it. I don't have the eyesight for any relatively long range accuracy testing for my handguns. For rifle, I'm still working on trying to figure out what I consider good or bad, I just haven't spent enough time working up rifle loads to say I'm finished developing any load I've worked up so far, I'm too aware of how much I don't know about rifle to be confident anything is good enough to be finished. I'm still surprised by things with some of my pistol loads, but it's not usually anything that makes me feel I need to go back and change to get it right.

Shooting the chronograph, I'm stunned more of you don't feel the same. The whole not pointing at what you're not willing to destroy thing i took you much to heart, or care to much about the chronograph i guess. Magneto speed isn't good for pistol, and a lab radar is just ridiculously priced in my opinion. I could kill 5 of my current chronograph and might almost have enough to buy another for the price of that thing. I also hear it's a bit quirky to get it to work right. I'll stick to wincing every time I pull the trigger and save the money. I'll probably need it to afford primers anyway.
 
I modified the Audette ladder test. I can get really good results with about 20 rounds.
Handgun and iron sight rifles get ocw test.
 
South Prairie Jim said:
ill go out on a limb her and say that pressure is felt in bolt lift resistence as the charges increase the cases exhibit radial expansion to the chamber walls first then in CBTD so once I start feeling that heavy resistance or pressure then I don't go further. I may give a case a quick look but Inspecting cases is done at the shop. Im also pretty sure a chronograph is not required to develop quality ammunition but as posted are very informative tool
Click to expand...
I can agree, but I still inspect at the range before moving to the next charge increment.
For those interested:
Pressure Signs
Load manuals and experienced reloaders frequently advise working a load up in small charge increments while watching for pressure signs (without any other details—typewriter cowboys are the worst).
Most people are unaware of all the signs (I certainly don't know them all), so, below is a partial list of pressure signs gleaned from numerous articles, along with possible alternate causes of these signs.

1.Case bulging, particularly near an unsupported part of the head.

2.Case crack along the side (may mean excess pressure, but may mean brittle, defective, draw mark scored, or worn out brass). I get this in about 2 out of every 100 .38 special rounds I fire and I don't remember the last time I saw this in .45 Auto, .44 Mag, or 9mm Luger. Also, I get this more often with nickel plated .38 Spl cases than brass cases.

3.Case head expansion (CHE) may mean high pressure, may mean nothing in isolated case, but ALWAYS a concern.

4.Case head separation (may mean high pressure, but may mean excess headspace or worn out brass).

5.Case splits in body in under 10 reloads-back loads down at least 2% (can also be due to ammonia vapor exposure or a brass defect in an individual case).

6.Case mouth split (may mean high pressure, but more often means case needed neck annealing).

7.Case pressure ring expansion (PRE) is not much more reliable than case head expansion but may mean pressure is excessive. I have found that with pistol rounds, I can track "pressure" quite well by measuring the pressure bulge about ⅛" above the extractor groove and compare to factory ammo, using the same head stamp virgin cases.

8.Case primer pockets getting loose in five reloadings or fewer.

9.Case excessive stretching (this is actually visible pressure ring area stretching which may be due to excess pressure or to excess headspace).

10.Extractor marks appear on case head in semi-auto rifle after incrementing powder charge up (may be high pressure or bad timing or an extractor standing proud on the bolt face).

11.Fired case won’t fit back into chamber.

12.Gas leak (see Primer Leaking, below).

13.Groups start to open up at or beyond a suspected maximum load pressure.

14.Hard bolt lift.

15.Incipient case head separations (partial case head separation).

16.Incremental increase in powder charge results in lower velocity or at least in no increase in velocity (may also mean uneven bolt lug contact being forced to touch down on both sides; watch for stringing on the bolt lug axis as additional symptom of this). I have found this to be quite repeatable for .44 Mag--I can track charge weight v velocity and reliably get a decrease in velocity at what other signs say is max or over max.

17.Primer blown (primer falls out when gun is opened; same as loose primer pocket).

18.Primer cratering (may mean high pressure, or it may mean a worn firing pin or firing pin tunnel, or may mean you have a new production Remington bolt with chamfered firing pin tunnel).

19.Primer flattening (may mean high pressure, or may mean long headspace; some loads always make flat primers; softer primer cups (Federal) flatten more easily than harder ones (CCI), so it also can mean nothing at all).

20.Primer mushrooming (may mean high pressure, or may mean long headspace).

21.Primer piercing (may mean high pressure or may mean incorrect firing pin protrusion or incorrect firing pin nose shape).

22.Primer leaking around primer pocket (may mean high pressure, may mean loose primer pocket in case, may mean damaged primer was inserted, may mean primer backed out too far during firing, which excessive chamber headspace makes possible).

23.Short case life -back load off at least 2% (under 10 reloads in non-self-loaders or with military brass in self-loaders, 6 or less in self-loaders with commercial brass).

24.Sticky or hard case extraction (especially in revolvers this is a positive sign to knock the powder charge down at least 5%).

25.Torn case rim (from hard extraction).

26.Primer pocket expansion (PPE; this is likely no more accurate than CHE (3., above), but is a more sensitive measure for those with tools that can measure the inside diameter of a primer pocket repeatably to the nearest ten-thousandth of an inch).

27.Ejector and extractor impressions on the case head (can also be due to ejector and extractor fit problems).

28.Increase in required trimming frequency (this is a sudden increase in case length growth per load cycle; it can be caused by excess pressure, but can also be a sign of increasing head space due to some other problem. It is especially common as a pressure sign in lever action guns because the greater span from bolt face to rear lug allows more steel stretch when pressure gets excessive.)

29.Increasing apparent headspace (this means the cases are coming out longer, including from casehead to shoulder. It can mean bolt lug setback, which is usually an extreme pressure sign. It can also mean a loose barrel or an improperly set Savage barrel. Whatever the cause, the gun should go straight to the gunsmith for inspection.)

30.Gas or Flame Cutting of revolver top strap. (Can also be due to excessive barrel/cylinder gap that needs correction.)

31.Gas cutting of rifle bolt face by gas leaks around primer pocket. (Can also be result of occasional leaks from normal rounds firing, as is observed in many military gun bolts.)

So, if there is a change in one of these signs from one increment to the next, take note and don't just blindly keep shooting.
 
I take a much simpler approach than most. I'm about to gore the sacred cow of folks that have thousands of dollars of gear and a painstaking process carefully sorted out over many years and tonnage of components to wring the most minute improvement in accuracy out of their loads/rifles, so if you are in that boat, you may wish to look away. My basic approach is as follows.

1. Review existing data, including first hand reports, talking to fellow shooters, my notes from similar applications, perhaps a question on this forum to find a likely candidate.
2. Start 5-10% below maximum with book COL. 2x 5 shot groups after 3 fouling shots with random ammo I usually have lying about to use up. Increase at roughly 1.5-2.5% increments to maximum power level desired, depending on my familiarity with the cartridge and component combination.
3. Compare precision across the groups, and decide if changes are needed or if load is suitable for purpose.
4. Tweak or abandon component combination or C.O.L. as dictated by #3,

My check list is:
1. Safe load?
2. Consistent load?
3. Suitable for intended use?
4. Load, shoot, be happy.

This approach has guided me to an OTC high power Master Card with a service rifle shooting in mostly open class matches, a CMP Distinguished badge, and consistent gold and silver scores with vintage bolt service rifles and the M1Garand, as well as countless game animals and varmints.
 
A friend uses Red Dot to load everything in pistol calibers from 9mm to 44 magnum, and in all of his shotshell trap loads. My goodness, does he get mileage....out of 8 lbs of Red Dot, he could launch projectiles around the world 80 times over again if you end for ended them.
Ive got Win 231 as my efficient powder for target loads. Its in the hopper as we speak.
 
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