Could use some help setting up a ladder test

[Dimner]

Hi everyone. I recently obtained access to a range that has benches and targets at 100, 200, 300 and 500. Previously i only had access to 100 and 200 yard ranges, so I did all my load development by analyzing groups at those distances. Well, now that I can, I would like to try a ladder test. Not because I need to, but I'd like the experience and learning from having done it.

The rifle that I have for the test (unless I wait another month) is a sporterized tikka 30-06 with a Douglas barrel. It shoots great, I've been able to get a load with N150 and 178g ELD-M that shoot 5/8 moa (4 shot groups, tested at 100, verified at 200) off the bench. I have a sightron S2 36x on it for load dev and testing.

So my first question is... Will I be able to interpret results from a ladder test with a sporterized setup like this? Or is it a waste of components because the target will have too much 'noise'. My instinct is that a rifle needs to have a certain baseline level of accuracy/precision before a ladder test becomes feasible.

If the rifle is good to go, here's what I would like put through the ladder test. 178g ELD-X again with VV N150. Same brass(Lapua) same primers (CCI 200) and same brass prep. The ELD-X are a little different in OAL and bullet base to ogive than the ELD-M. So they are not a 1:1 replacement and should be a good test.

So setting up the ladder, this is also where I need everyone's experiences....

• What powder percentage increments are useful? How wide is too wide and how little is too little?
• Will 300 yards be sufficient?
• 3 or 4 rounds per charge weight?
• Should I round robin the loads or shoot each charge in succession?
• What is the most useful aim point? Something like an orange 3 or 5 inch round target sticker?
• I'm planning on using a white corrugated presentation board for the target. They come 48x36 inches. Cut down or leave as is?
• Yes I will be using wind flags (home made). I have 5. 0, 50, 100, 200, 300?
• Yes I plan on coloring the bullets so they show up on the target board

Thank you all for helping as I plan out this test. The new range is an hour away and I'd rather not screw up the test 2 or 3 times before I get the hang of it

 

[ShtrRdy]

I would recommend this video if you haven't already watched it:

 

[std7mag]

This is the method I have been using.
I do most of my testing at 100 yards.
But most of my rifles are geared towards hunting.

Long Range Load Development

Written by Sierra Bullets Product Development Manager Mark Walker [First published July 3, 2014] Since I just put a new barrel on my F-class rifle this spring, I figured it might be a good time t…

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For load development I use a sheet of white poster board. On this I use a Sharpie and draw a long horizontal line, and a smaller vertical line.

Make sure you give your barrel plenty of time to cool down.
I'll usually do 0.3gr increments.
3-5 minutes to shoot 3 shots. Keeping track of the shots through the scope, or spotting scope.
I also have a piece of paper with a rough facimally of the target that I mark my shots on for reference.

With the other shooters, sometimes you have to wait a while to go to your target.

 

[Doom]

Hi everyone. I recently obtained access to a range that has benches and targets at 100, 200, 300 and 500. Previously i only had access to 100 and 200 yard ranges, so I did all my load development by analyzing groups at those distances. Well, now that I can, I would like to try a ladder test. Not because I need to, but I'd like the experience and learning from having done it.

The rifle that I have for the test (unless I wait another month) is a sporterized tikka 30-06 with a Douglas barrel. It shoots great, I've been able to get a load with N150 and 178g ELD-M that shoot 5/8 moa (4 shot groups, tested at 100, verified at 200) off the bench. I have a sightron S2 36x on it for load dev and testing.

So my first question is... Will I be able to interpret results from a ladder test with a sporterized setup like this? Or is it a waste of components because the target will have too much 'noise'. My instinct is that a rifle needs to have a certain baseline level of accuracy/precision before a ladder test becomes feasible.

If the rifle is good to go, here's what I would like put through the ladder test. 178g ELD-X again with VV N150. Same brass(Lapua) same primers (CCI 200) and same brass prep. The ELD-X are a little different in OAL and bullet base to ogive than the ELD-M. So they are not a 1:1 replacement and should be a good test.

So setting up the ladder, this is also where I need everyone's experiences....

• What powder percentage increments are useful? How wide is too wide and how little is too little?
• Will 300 yards be sufficient?
• 3 or 4 rounds per charge weight?
• Should I round robin the loads or shoot each charge in succession?
• What is the most useful aim point? Something like an orange 3 or 5 inch round target sticker?
• I'm planning on using a white corrugated presentation board for the target. They come 48x36 inches. Cut down or leave as is?
• Yes I will be using wind flags (home made). I have 5. 0, 50, 100, 200, 300?
• Yes I plan on coloring the bullets so they show up on the target board

Thank you all for helping as I plan out this test. The new range is an hour away and I'd rather not screw up the test 2 or 3 times before I get the hang of it

You tell us a lot about how you are going to test but you have said anything about what you expect or what the intended use of the rifle will be.

Ladder testing can be tricky and you need to consider some of the elements that come into play based on the distance that you will be shooting. Most important is the use of quality components!

Shooting a ladder at 100yds is going to tell you more about the rifle, the shooter, and some of the repeatable elements of the cartridge (seating depth, runout). In particular it will show the repeatability of the barrel position with different loads. It will not show much about the velocity variation since for most center fire rifles a 100 fps velocity change will result in less than a caliber variation in point of impact. A load that doesn't group well and without consist point of impact isn't going to perform well at longer distances. One that does shoot well at 100yds but falls apart at distance is likely a load with high SD/ES. A chronograph can provide better velocity data than any ladder test.

As the distance increases then the dispersion due to environmentals, barrel/cartridge and velocity differences increases and at some point the velocity becomes dominant so that the ability to load low ES/SD becomes an issue. Without a chronograph velocity variations due to normal loading variations can create false "nodes".

As more and more statistically significant data has become available it appears that what we as hand loaders have referred to as powder nodes in the past seems to be more related to barrel harmonics than actual powder charge. The change in powder charge/velocity changes barrel time which is related to the harmonic response of the barrel.

It's also important to have reasonable expectations for the rifle and for its intended use. If this is a hunting rifle the concept of precision is not nearly as important as repeatable accuracy/point of impact for the first couple of shots from a cold barrel. Group size is of lesser importance. Shooting competitive matches for groups is totally different.

 

[jdj71]

You tell us a lot about how you are going to test but you have said anything about what you expect or what the intended use of the rifle will be.

Ladder testing can be tricky and you need to consider some of the elements that come into play based on the distance that you will be shooting. Most important is the use of quality components!

Shooting a ladder at 100yds is going to tell you more about the rifle, the shooter, and some of the repeatable elements of the cartridge (seating depth, runout). In particular it will show the repeatability of the barrel position with different loads. It will not show much about the velocity variation since for most center fire rifles a 100 fps velocity change will result in less than a caliber variation in point of impact. A load that doesn't group well and without consist point of impact isn't going to perform well at longer distances. One that does shoot well at 100yds but falls apart at distance is likely a load with high SD/ES. A chronograph can provide better velocity data than any ladder test.

As the distance increases then the dispersion due to environmentals, barrel/cartridge and velocity differences increases and at some point the velocity becomes dominant so that the ability to load low ES/SD becomes an issue. Without a chronograph velocity variations due to normal loading variations can create false "nodes".

As more and more statistically significant data has become available it appears that what we as hand loaders have referred to as powder nodes in the past seems to be more related to barrel harmonics than actual powder charge. The change in powder charge/velocity changes barrel time which is related to the harmonic response of the barrel.

It's also important to have reasonable expectations for the rifle and for its intended use. If this is a hunting rifle the concept of precision is not nearly as important as repeatable accuracy/point of impact for the first couple of shots from a cold barrel. Group size is of lesser importance. Shooting competitive matches for groups is totally different.

What he said and let me emphasize the need for a chronograph.
Good luck with your project.

 

[Dimner]

Thanks everyone for the feedback so far. Yes, I have a labradar that I will be using.

The rifle will primarily be for hunting. But that's not really the point of the test. I am more interested in learning this load development technique. I already have a good hunting load with a Sierra bullet that will shoot smaller groups than I need for hunting and at longer distances than I will ever take a shot on game. So this test is just to get the experience before my new target rifle is done being built. I also guess this test will be good to have data on a backup load.

That link to the blog from Sierra, is the basic method I'll be using. I just need some help with the specific questions I put in the original post.

The most important of those questions is how many rounds and what method to shoot.

• I see some folks post that do 3 rounds per charge weight in increments, shooting all at the same aim point, and kind of triangle together where the three land.
• I see some that do 1 round per charge weight incremented and shot at one aim point. (like the fella in the Sierra blog)
• I see some that do 1 round per charge weight incremented and shot at one aim point, but perform the test twice.

I would like to do this first time ladder in a way that factors in my inexperience in ladder testing. So I have ruled out just 1 round per charge at one aim point (like the Sierra blog). Maybe I'll do option 3?

Distance wise, I'm really only considering doing this test at 300 or 500.

 

[DLT]

Thanks everyone for the feedback so far. Yes, I have a labradar that I will be using.

The rifle will primarily be for hunting. But that's not really the point of the test. I am more interested in learning this load development technique. I already have a good hunting load with a Sierra bullet that will shoot smaller groups than I need for hunting and at longer distances than I will ever take a shot on game. So this test is just to get the experience before my new target rifle is done being built. I also guess this test will be good to have data on a backup load.

That link to the blog from Sierra, is the basic method I'll be using. I just need some help with the specific questions I put in the original post.

The most important of those questions is how many rounds and what method to shoot.

• I see some folks post that do 3 rounds per charge weight in increments, shooting all at the same aim point, and kind of triangle together where the three land.
• I see some that do 1 round per charge weight incremented and shot at one aim point. (like the fella in the Sierra blog)
• I see some that do 1 round per charge weight incremented and shot at one aim point, but perform the test twice.

I would like to do this first time ladder in a way that factors in my inexperience in ladder testing. So I have ruled out just 1 round per charge at one aim point (like the Sierra blog). Maybe I'll do option 3?

Distance wise, I'm really only considering doing this test at 300 or 500.

Doing 3 will depend on barrel profile and cartridge. My 6 creed gets hot after 3 with a sendero profile. In this weather it takes a little while to cool back down. A barrel cooler will help as well as heavier barrel and not so hot chambering. I try to do em early in the morning before the sun, wind , and temp get up

 

[RabbitSlayer]

For a bigger case like 30-06 or creedmoor, .5 gr increments are the ticket. In a smaller .223 size case .3 is good.

IMHO unless you will be happy with a light load, there is no reason to waste time or energy on the low end. Start with a mid level charge.

100 yards is the ticket. It will remove the environmental variables as much as possible.

Shooting a sporter weight gun in a sporter stock is difficult. You gotta drive it and manage recoil. This lite grip thumb on the side stuff doesn't work so good. Watch snipers hide and all their content on recoil management. It really helped me. Keep your goals realistic. Most folks on here are shooting heavy target guns.

 

[std7mag]

Doing it at 100 yards with single shots per 0.3gr increments I've only had 3 occasions where I had to redo it at 200 yards.
And those were with 3 different rifles and 3 specific powder/bullet combinations.

 

[Doom]

Dan Newberry developed a method call Optimal Charge Weight (OCW) which used 3 shot groups shot at 100yds and looked for adjacent charges with the same point of impact. It is a system that effectively finds a charge where small changes in velocity has very little impact on the point of impact. What it really does in my opinion is find a charge where the barrel isn't moving much with changes in barrel time. It is a form of ladder test and using 3 shots helped reduce the chance of a random shot throwing off the results. It may or may not produce a load with the smallest groups.

This is the method I normally use with the caveat that I don't load 3 for every charge. I load one for several of the lower charges just for pressure checks and then load three when I get to 94% of my expected maximum load.

If I were working up a new load today the change I would make is to use a target that puts all of the groups on one horizontal plane as opposed to the one that I've used in the past. I would also try one that Kieth Glascock suggested which uses a rectangle as opposed to a diamond or circle. The rectangle allows you to align the crosshairs on the corner of the rectangle which is very repeatable.

As for the chronograph, I do not use one when developing a load because I do not normally care about where my velocity is for the ranges I normally shoot. I will test once I pick the load. The data can help analyze issue that show up on target at distance but ultimately the target rules.