How do you perform your ladder tests/load development

[Kelsey Cooter]

Run me through how you blokes develop a load from start to finish?
How much do you jump up in weight on your ladder tests?
How many ladder tests do you do?
What is your starting distance from lands?

[SCJ429]

Add .3 of a grain until I am getting worried and slow it down to 0.2.
If I don't get the speed I am looking for and no pressure signs I do another ladder. If it is the 6.5x55 Swede you may have to do several more.
I start off 20 thou off the lands or if feeding from a magizene, what ever will fit.

[straightshooter]

I have to admit I am impressed by the credulous nature of those that place any faith in the value of a so called 'ladder test'.
You would be far better served gaining an understanding of what are the physics and mechanics of firing a rifle and a grasp of statistical analysis, and thereby acquiring at least some resistance to any belief in myth and magic.
Otherwise you will spend the rest of your shooting life trying to 'make a silk purse out of a sow's ear'.

[Oldbloke]

Add .3 of a grain until I am getting worried and slow it down to 0.2.
If I don't get the speed I am looking for and no pressure signs I do another ladder. If it is the 6.5x55 Sweed you may have to do several more.
I start off 20 thou off the lands or if feeding from a magizene, what ever will fit.

What he said. But i dont care about velocity. I just want accurate enough for hunting. We arnt all long range target shooters.

[SCJ429]

I have to admit I am impressed by the credulous nature of those that place any faith in the value of a so called 'ladder test'.
You would be far better served gaining an understanding of what are the physics and mechanics of firing a rifle and a grasp of statistical analysis, and thereby acquiring at least some resistance to any belief in myth and magic.
Otherwise you will spend the rest of your shooting life trying to 'make a silk purse out of a sow's ear'.

Not quite sure what you are saying here but in order to have some statistics to analyse you need to shoot a ladder test.. At the most basic level the test will tell you how fast you can push the bullet. Other information is around possible nodes as indicated by clusters of bullets with similar velocity, this gives you a place to start with load development.

I want to find a node close to the maximum safe velocity avalible. This is why I increase by 0.2 of a grain near the top, you won't miss the node.

[straightshooter]

You can't wilfully ignore all the other possible variables in firing a shot and imagine that any change is purely attributable to a slight change in the quantity of powder. Particularly if it is merely a 2 shot 'group' shot at a shortish range as is often the case with these so called ladder tests.

[marksman]

tut tut tut
just do an ocw to find the sweet spot for your load to hopefully get a minimum 1/2 moa
http://optimalchargeweight.embarqspace.com/

[bladeracer]

You can't wilfully ignore all the other possible variables in firing a shot and imagine that any change is purely attributable to a slight change in the quantity of powder. Particularly if it is merely a 2 shot 'group' shot at a shortish range as is often the case with these so called ladder tests.

Ladder tests are one-shot "groups", shot at 200m or more to look for elevation stability across charge weights. I tend to agree that a single round is not enough to bet the house on so I would suggest to anybody that they shoot several ladders and confirm the data are accurate before loading up several thousand rounds for the season. For that reason I prefer to just shoot 5rd groups and monitor the horizontal and vertical shift from point-of-aim. Ladders are best confined to long-range precision rifles that already shoot very, very well, before any load development, and by a shooter capable of harnessing that precision with _every_ shot. You never want to think to yourself, "did I pull that shot?" during a ladder test If you don't have the ability then it is possible to shoot only across a chronograph and look for a velocity node (where velocity remains stable across several charge weights) without considering accuracy - I'm not convinced by this method though. For me, the end result of "holes in paper" is what wins the match, not how close the velocity is or how stable the elevation shift is, so we might as well just use "holes in paper" as our standard.

Something I tried a few times testing .22LR ammo was to shoot a page of targets putting a single round on each, then going around four more times to end up with ten 5rd groups . Whether it has any real value I can't say, but it does ensure you aren't shooting every shot in the group without changing your shooting position and sight picture for every shot. Real-world shooting rarely involves firing several shots at the same animal without changing your position, or the target's position.

Keep in mind that the primary purpose of a ladder to test is to minimise barrel wear, ie load development with the least possible amount of shooting.

[bladeracer]

Run me through how you blokes develop a load from start to finish?
How much do you jump up in weight on your ladder tests?
How many ladder tests do you do?
What is your starting distance from lands?

First I get a bunch of different bullets from minimum to maximum weights, even some heavier than I would expect to stabilise. If you only have a single-purpose for the rifle then you can probably just test one or two bullets best suited. Then I look at the ADI data to determine the best powders to try, looking for most velocity with least pressure, ideally with compressed loads at the top end.
Then I load some cheap-bullet, mid-range AR2206H loads and go shooting

I don't hunt much past 300m, and I don't shoot any competitions, so I don't need half-MoA accuracy - consistent sub-MoA regardless of my field position is all I need. Ladders are shot for long-range precision, well past 300m, with rifles that are shooting well under 1MoA already, before load development. I generally don't bother with ladder tests, I just shoot 5rd groups at 100m for accuracy and patterning, then shoot the more promising loads out to 300m to confirm they work, and record the trajectory and real-world BC. That's about as far as I go most of the time, but if I'm still hunting an improvement, and am seating long enough, then I'll play with the seating depth a bit. I don't bother trying to go closer than 20-thou as you'd need very high-end bullets and a custom ogive gauge to keep them at a consistent jump.

I see no value in shooting a 300m ladder with a rifle that groups much more than 1.5MoA, with 135mm group capability you're just going to get confused trying to decipher where they are on the ladder. With something like that I'd just shoot it over the chrono and try to find a velocity node rather than an elevation node. If I don't shoot a ladder I do record group position from point-of-aim, and keep photos of my groups for future reference. I also record the velocities. It's worth noting that while I do shoot development off a bench sometimes, and even off a rest, most of it is just the bipod with no rear bag, basically the same as I'd expect to shoot it in the field. I do sometimes shoot with bags front and rear to see just how tight a rifle can group, but I don't consider such efforts to be realistic. With .22LR I have been using a rear bag at longer-ranges to avoid spraying bullets all over while trying to find the gong at 300m or more, 240m is about the furthest I can consistently stay on the five-inch gong currently with .22LR, once I've worked out what the wind is doing.

Charges would be around 1% of case capacity, .3gn increments on smaller cartridges (say up to 30gn), 0.5gn on mid-size (up to about 50gn), and a full grain on bigger stuff. If I were loading for the Hornet or anything else in the 10gn range, I'd probably work in .2gn, and for the .50BMG I'd probably go 5gn increments with its 220gn+ loads. I load ten rounds of each charge weight to shoot two sets of groups, on different days if possible, plus some of the aforementioned AR2206H loads to warm the barrel beforehand. While I do load past maximums I have no interest in chasing velocity, I just like to get a feel for exactly where the pressure limits are. Most of my ammo is loaded below factory-spec as I consider precision to far outweigh velocity. I do load above maximums listed by ADI, but I don't bother loading anything that exhibits any pressure signs at all during testing, regardless of how accurate it might be.

I load to feed from the magazine, but my Rugers with AICS mags allow significantly longer than the standard 2.260" mag length for .223Rem, I load the 80gn ELDM at 2.450" (nearly 5mm longer than standard spec). And I also play with single loads that are too long to feed through the mag just to see if they shoot any better.

I'm currently working up long-range 6.5x55mm loads with the 147gn ELDM and AR2206H from 33.0gn to 35.5gn. In my M38 the 147gn ELDM touches at 3.265" COAL so I'm loading at 3.220". Despite being 70-thou over the 3.150" spec they feed from the magazine just fine.

[Kelsey Cooter]

Add .3 of a grain until I am getting worried and slow it down to 0.2.
If I don't get the speed I am looking for and no pressure signs I do another ladder. If it is the 6.5x55 Sweed you may have to do several more.
I start off 20 thou off the lands or if feeding from a magizene, what ever will fit.

What he said. But i dont care about velocity. I just want accurate enough for hunting. We arnt all long range target shooters.

Thank you for giving actual imput on how you do your ladder tests SCJ & Oldbloke

[Kelsey Cooter]

Run me through how you blokes develop a load from start to finish?
How much do you jump up in weight on your ladder tests?
How many ladder tests do you do?
What is your starting distance from lands?

First I get a bunch of different bullets from minimum to maximum weights, even some heavier than I would expect to stabilise. If you only have a single-purpose for the rifle then you can probably just test one or two bullets best suited. Then I look at the ADI data to determine the best powders to try, looking for most velocity with least pressure, ideally with compressed loads at the top end.
Then I load some cheap-bullet, mid-range AR2206H loads and go shooting

I don't hunt much past 300m, and I don't shoot any competitions, so I don't need half-MoA accuracy - consistent sub-MoA regardless of my field position is all I need. Ladders are shot for long-range precision, well past 300m, with rifles that are shooting well under 1MoA already, before load development. I generally don't bother with ladder tests, I just shoot 5rd groups at 100m for accuracy and patterning, then shoot the more promising loads out to 300m to confirm they work, and record the trajectory and real-world BC. That's about as far as I go most of the time, but if I'm still hunting an improvement, and am seating long enough, then I'll play with the seating depth a bit. I don't bother trying to go closer than 20-thou as you'd need very high-end bullets and a custom ogive gauge to keep them at a consistent jump.

I see no value in shooting a 300m ladder with a rifle that groups much more than 1.5MoA, with 135mm group capability you're just going to get confused trying to decipher where they are on the ladder. With something like that I'd just shoot it over the chrono and try to find a velocity node rather than an elevation node. If I don't shoot a ladder I do record group position from point-of-aim, and keep photos of my groups for future reference. I also record the velocities. It's worth noting that while I do shoot development off a bench sometimes, and even off a rest, most of it is just the bipod with no rear bag, basically the same as I'd expect to shoot it in the field. I do sometimes shoot with bags front and rear to see just how tight a rifle can group, but I don't consider such efforts to be realistic. With .22LR I have been using a rear bag at longer-ranges to avoid spraying bullets all over while trying to find the gong at 300m or more, 240m is about the furthest I can consistently stay on the five-inch gong currently with .22LR, once I've worked out what the wind is doing.

Charges would be around 1% of case capacity, .3gn increments on smaller cartridges (say up to 30gn), 0.5gn on mid-size (up to about 50gn), and a full grain on bigger stuff. If I were loading for the Hornet or anything else in the 10gn range, I'd probably work in .2gn, and for the .50BMG I'd probably go 5gn increments with its 220gn+ loads. I load ten rounds of each charge weight to shoot two sets of groups, on different days if possible, plus some of the aforementioned AR2206H loads to warm the barrel beforehand. While I do load past maximums I have no interest in chasing velocity, I just like to get a feel for exactly where the pressure limits are. Most of my ammo is loaded below factory-spec as I consider precision to far outweigh velocity. I do load above maximums listed by ADI, but I don't bother loading anything that exhibits any pressure signs at all during testing, regardless of how accurate it might be.

I load to feed from the magazine, but my Rugers with AICS mags allow significantly longer than the standard 2.260" mag length for .223Rem, I load the 80gn ELDM at 2.450" (nearly 5mm longer than standard spec). And I also play with single loads that are too long to feed through the mag just to see if they shoot any better.

I'm currently working up long-range 6.5x55mm loads with the 147gn ELDM and AR2206H from 33.0gn to 35.5gn. In my M38 the 147gn ELDM touches at 3.265" COAL so I'm loading at 3.220". Despite being 70-thou over the 3.150" spec they feed from the magazine just fine.

Cheers Bladeracer,
When you say -

I just shoot 5rd groups at 100m for accuracy and patterning, then shoot the more promising loads out to 300m to confirm they work, and record the trajectory and real-world BC.

Those 5 rounds groups at 100m, is that just a few charges you've picked or are you doing a ladder test?

[bladeracer]

Cheers Bladeracer,
When you say -

I just shoot 5rd groups at 100m for accuracy and patterning, then shoot the more promising loads out to 300m to confirm they work, and record the trajectory and real-world BC.

Those 5 rounds groups at 100m, is that just a few charges you've picked or are you doing a ladder test?

Five rounds would not be a ladder, ladders are shot with single rounds of each charge weight. https://www.youtube.com/watch?v=ACyfeeBHVOA&feature=youtu.be

The 6.5x55mm AR2206H loads I have in front of me are ten rounds of each charge from 33.0gn to 35.5gn in .5gn increments. I'll shoot them in two strings of five-round groups at 100m, ideally on different days so I have a true indication of the potential of each charge weight. The charge(s) that show the most promise I will then load 50-60 depending on how much empty brass I have, and shoot a bunch of 100m groups to confirm it lives up to the limited data I got from the initial development groups. I'll also shoot these out to 300m to record the trajectory over several distances to calculate the real-world BC and to confirm they remain tight at longer ranges.

[bladeracer]

Not quite sure what you are saying here but in order to have some statistics to analyse you need to shoot a ladder test.. At the most basic level the test will tell you how fast you can push the bullet. Other information is around possible nodes as indicated by clusters of bullets with similar velocity, this gives you a place to start with load development.

I want to find a node close to the maximum safe velocity avalible. This is why I increase by 0.2 of a grain near the top, you won't miss the node.

I don't believe there is any _need_ to shoot ladder tests at all. You need to do some shooting to gather data you can use, but a ladder test really just reduces the amount of data you gather, which I don't consider to necessarily be a good thing. I contend that you can usually gather a lot more useful data from shooting twenty five-round groups than you can from just shooting ten rounds during development. But if your rifle only has an 800rd barrel life you risk trying to complete the season with a rifle shooting sub-optimally because of the extra hundred rounds you put through it during load development.

[SCJ429]

The ladder test is a good place to start, you have to begin any loading with a powder charge you can guarantee is safe. You will probably never load this charge again so why not load only one. Then increase the powder charge until you reach a velocity where you are happy. This might be when you see pressure signs. You now have a range in which to conduct load development. Sounds like a painless way to get started.

[SCJ429]

Bladeracer I note you said you were doing load development for the 6.5x55 using 147 ELDM. Your load testing was from 33 to 35.5 grains of powder, 2208?. How did you come up with that powder range?

I was testing the same case using 143 grain ELDX and with a ladder test I knew I could shoot in excess of 3000 fps. I found the node at just under 2950 fps after seeing a cluster around that speed. The SD for that load is around 3 fps. A fairly painless process from what can be a challenging case to get right.

[marksman]

the ladder test is looking for a sweet spot in velocity
just do an ocw test

[bladeracer]

Bladeracer I note you said you were doing load development for the 6.5x55 using 147 ELDM. Your load testing was from 33 to 35.5 grains of powder, 2208?. How did you come up with that powder range?

I was testing the same case using 143 grain ELDX and with a ladder test I knew I could shoot in excess of 3000 fps. I found the node at just under 2950 fps after seeing a cluster around that speed. The SD for that load is around 3 fps. A fairly painless process from what can be a challenging case to get right.

AR2206H. I didn't come up with the range, I used numbers offered by ADI - 32.5gn to 35.8gn for the 140/142gn jacketed bullet.
As I explained, I have zero interest in trying to push either the rifle or the brass to some arbitrary maximum velocity. If I can get good accuracy at 2500-2600fps I'll be more than happy. I need to do similar with my M96 in the hope of finding a single load that shoots equally well in both rifles if possible. I also have zero interest in SD or ES, just accuracy.

My "standard" load is the 95gn VMax on 41.0gn of AR2206H at 2.850". This load makes 2960fps in my M38 and maintains MoA consistently.

[SCJ429]

I understand your approach but for other people they are not chasing an arbitrary maximum velocity but exploiting the potential of their case. Why have the hairy chested Swede and shoot it at Grendel speeds?

I also find that accuracy is linked to low SD. You don't need to know the SD to have accurate ammunition but knowing the SD can help get you there.

[bigfellascott]

Never done a ladder test (wasn't known back in my day) I just start my reloads at min recommended in the reloading manual and just load 3 rounds of each load working up in .3gn increments until I find a load that shoots ok and leave it at that, I don't fluff around with seating depths much if at all either, I keep things basic and I find that's good enough for my needs.

Sometimes I don't even test loads for accuracy or I might just load what I think is a good enough load, put a couple of shots on paper to see if they are heading in the right direction and then go out and confirm it shoots fine in the paddock.

[bladeracer]

I understand your approach but for other people they are not chasing an arbitrary maximum velocity but exploiting the potential of their case. Why have the hairy chested Swede and shoot it at Grendel speeds?

I also find that accuracy is linked to low SD. You don't need to know the SD to have accurate ammunition but knowing the SD can help get you there.

Exploring the limits is fine, we all enjoy experimenting, and trying to find the maximum possible velocity is part of that. But if I have no intention of shooting such hot loads all the time, there's little point in my doing that sort of load development. If I just want to know how fast I can push it I can simply shoot them through a chrono into the dirt without bothering with targets. If I want to get the best accuracy, I can shoot at paper without bothering to measure velocities. One of the things that drove F-Class I think was the need to optimise accuracy while maintaining enough velocity to be stable at the target distance. With modern bullet designs, is that 1600m stability an issue still? Do modern bullets lose all stability transitioning and become hopelessly inaccurate?

I don't see any need to work any of my rifles at maximum load, and I like my brass to last. Instead of trying to punch a 150gn bullet at 3200 out of the 6.5x55mm I'd find a better bullet, or use something else that can do that, again without pushing that rifle to its limits either.

When they change the laws so we can only have a single-shot .22LR and we need to find ways of getting it to make similar power to .30-06 then I'll investigate ways of doing so. Nowadays we have a virtually endless choice of chamberings we can use to suit any situation we can come up with. If you need to hit harder than the cartridge you're using, use a cartridge that hits harder.

The OP asked us for our specific methods, and yours is as valid as anybody else's. The OP just needs to delineate exactly what end result he requires.

[bladeracer]

Never done a ladder test (wasn't known back in my day) I just start my reloads at min recommended in the reloading manual and just load 3 rounds of each load working up in .3gn increments until I find a load that shoots ok and leave it at that, I don't fluff around with seating depths much if at all either, I keep things basic and I find that's good enough for my needs.

Sometimes I don't even test loads for accuracy or I might just load what I think is a good enough load, put a couple of shots on paper to see if they are heading in the right direction and then go out and confirm it shoots fine in the paddock.

When I was learning to load, I was working in .1gn increments because I thought even single kernals of powder mattered
Yep, it's important not to lose sight of your requirements. There is nothing to be gained in developing a 1000m sub-MoA load for a .222Rem, or a .44 Magnum.

With my milsurps I generally just pluck a figure out of the sky and load some rounds up and see how they shoot. I almost always start with some Trailboss loads of 10-15gn just to get some shooting happening while I work on proper load development.

Looking at my logbook, when I bought the M38 in October 2016 I loaded five round groups with the 95gn VMax on AR2206H from 40.0gn to 42gn in .5gn increments. These were the very first rounds I fired in the rifle - I hadn't even fired a sighting round, just bore-sighted it. The first five groups were under 1MoA and virtually on top of each other, except the 40.5gn group that fell 30mm high left. The 42.0gn group went out to 2MoA. Velocities were: 40.0gn 2877fps ES87, 40.5gn 2851fps ES116 -27fps, 41.0gn 2951fps ES57 +100fps, 41.5gn 2978fps ES60 +27fps, and 42.0gn 3032fps ES48 +53fps. I wouldn't even attempt to put any value on SD calculation off just five rounds. I like to record the increase in velocity with charge weight as indicating "burn efficiency". Stepping up .5gn from 40.5gn to 41.0gn gave me an average 100fps increase in velocity, which I take to mean the boiler room is burning the fuel most efficiently. Adding another .5gn only makes me 27fps, adding a full grain only makes me 53fps, and tosses accuracy out the window.

Based on these first 25rds I loaded 100rds for general shooting, they still maintain MoA and I've loaded 300 more of them since. The last group I shot through the chrono last year gave me 2957fps ES48 and an SD of 9.5 (2943 2962 2969 2962 2949) so I think I chose well.

[bladeracer]

Looking at my logbook, when I bought the M38 in October 2016 I loaded five round groups with the 95gn VMax on AR2206H from 40.0gn to 42gn in .5gn increments. These were the very first rounds I fired in the rifle - I hadn't even fired a sighting round, just bore-sighted it. The first five groups were under 1MoA and virtually on top of each other, except the 40.5gn group that fell 30mm high left. The 42.0gn group went out to 2MoA. Velocities were: 40.0gn 2877fps ES87, 40.5gn 2851fps ES116 -27fps, 41.0gn 2951fps ES57 +100fps, 41.5gn 2978fps ES60 +27fps, and 42.0gn 3032fps ES48 +53fps. I wouldn't even attempt to put any value on SD calculation off just five rounds. I like to record the increase in velocity with charge weight as indicating "burn efficiency". Stepping up .5gn from 40.5gn to 41.0gn gave me an average 100fps increase in velocity, which I take to mean the boiler room is burning the fuel most efficiently. Adding another .5gn only makes me 27fps, adding a full grain only makes me 53fps, and tosses accuracy out the window.

Based on these first 25rds I loaded 100rds for general shooting, they still maintain MoA and I've loaded 300 more of them since. The last group I shot through the chrono last year gave me 2957fps ES48 and an SD of 9.5 (2943 2962 2969 2962 2949) so I think I chose well.

Thought I might as well update this.
Friday I realised the wind had died away completely, so I went out and set out some targets and the chrongraph, then came and grabbed the M38 and my 147gn ELDM test ammo, still no wind - awesome!
I wanted to shoot some of the Norma factory 139gn FMJ stuff for a baseline and to warm the bore. One round in the box had already had the tip filed off so I fired that one as a warmer, hoping to put five more into a group for reference. Unfortunately, I've had the scope and mount off and the zero was miles out so I burned up most of those just zeroing. Velocity was 2464fps, ES48, SD 23. I didn't bother shooting a group as well as the wind was already getting serious.

I moved to the 33.0gn load. The Norma stuff had a rolling boom, the AR2206H had a very distinct sharp crack to it. The wind was really howling by this point and I figured groups would be totally random and worthless so I'd really just be working with velocities.

33.0gn gave me 2135fps, ES48, SD18, and the group was 51mm.
33.5gn gave me 2198fps, ES25, SD9 and +63fps over the 33.0gn load. Group was 48mm.
34.0gn gave me 2204fps, ES44, SD15 and +6fps. The group was 67mm.
34.5gn gave me 2225fps, ES33, SD11 and +21fps with the group at 60mm.
35.0gn gave me 2266fps, ES73, SD15 and +41fps with a group of 59mm.
35.5gn gave me five chrono errors and no group as the wind was flapping my targets across the backboard - no useful data at all.

No pressure signs, although the edge of the primer is starting to flatten at 35.0gn.
Cases stretched 2-thou at 34.5gn, 5-thou at 35.0gn, and 10-thou at 35.5gn.

Although I really can't make any determinations based on the accuracy due to the conditions, I'm thinking these 36.5mm bullets might enjoy more velocity, so I'll load further up past ADI max and hope we get some calm days.