Ladder tests

I do ladder.
Depending on cartridge i either do 100 yards, or 200 yards.
I go from start upwards 0.3 gr per round.
Look for 3 closest vertically. ( note, there may be more than one set)
I number the shots after 3 rounds on my target.
Middle of 3 closest vertically is your powder charge.
 
I've never used a ladder for loading anything but they work fine for accessing places you can't reach from the ground.
Seriously, I load to manual max or a predetermined velocity level. When I reach velocity and accuracy that fits my needs, I stop.
 
for long range load development I use Erik Cortina's 100 yard method


for analyzing the targets I use a program called Ontarget, it allows me to shoot several groups or targets separately then to overlay them as a single group. That accomplishes the same results as the OCW method except it is much easier to accomplish. Here is an example from a single target with the 4 groups overlayed to get a picture of all 40 shots in reference to the bull. It can also import the data from multiple targets onto one. The upgraded 34 dollar version is needed for target analysis of high shot count virtual groups from multiple targets

m6fWBoA.jpg
 
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You need more than 100yds for a ladder test or ocw.
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The farther out you shoot from 100 the more you increase the chance of wind/mirage/shooter error affecting the test. Factories and international champion shooters develop at 100 yards, even for long range. I think I will follow their lead

I only have a few plastic club level ribbons so don't take my word for it but the link I provided above was for a method developed by Erik Cortina who is a member of Team Lapua-Brux-Borden. He is a world class F-Class Champion.

A list of his accomplishments can be found here

http://www.lapua.com/en/lapua-team/lapua-team-usa/erik-cortina.html

I would bet he knows a thing or two about load development
 
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Follow whatever lead you want. You wont see enough of a difference in poi with .3gr in rements for a ladder or ocw at 100yds. Didnt say you couldnt load develop at 100.
Did you ask eric if used a ladder or ocw at 100?
 
Hdwhit by ladder tests I basically mean what std7mag described. Shooting 10 rounds with same point of aim at different powder charges to see if you can find a few that shoot close to each other vertically.
 
Follow whatever lead you want. You wont see enough of a difference in poi with .3gr in rements for a ladder or ocw at 100yds.
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whatever you want to believe, then believe. I tend to put more weight behind peoples methods that have walked the walk on the path I want to follow

I can honestly say that since I started using Cortina's load development my score went from an average of 191 to a average of 193.5 starting from the first match I began using ammo that had developed using that method and I have not even had time to fine tune the primers yet on main rifle. The first target of the first match I shot a 197 which is my highest score ever
 
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I use 10 shot groups and look for the nodes. It works and saves a lot of time and money. But you'll need a chrony, Magneto Speed or Labradar to track speed.

Here's a summary from the 6.5 Guys website:

I start 1.5 grains below my max load and load 10 shells ascending by .2 gr. So for the Swedemoor, 50.0, .2, .4, .6, .8, 51.0, .2, .4, .6, .8, 52.0.

Then I will shoot these over the chronograph and look for the nodes. A node will be a velocity flat spot where .4-.8 gr of powder doesn’t move the speedometer much. This example with Reloader 26 in my 6.5 Addiction with 140 RDFs, the flat spot is between 51.2 and 51.8 grains -velocity went from 3025-3033 fps. So, .8 grains of powder added a total of 8 fps. Therefore, the middle of my node is 51.5 grains.

Next I then load up 5 of the 51.5 grain load and shoot them over the chronograph and the extreme spread was 5 FPS. I have repeated this with H100V, H4350, 4831, 1000, Retumbo, RE 17,19, 22, 23, 26, wiN 760, 780, VV 160, 170, 560, 570 IMR 4451, 4955, 7828 and 7977. With all of these powders, 3020-3035 fps was an accuracy node without regard to the powder type.

Once I find the velocity node I load in the middle of it then fiddle with COAL until it shoots tiny groups with low low extreme spreads. You can have an accurate load at 100 yards that will not shoot past 600 yards because you have a high extreme spread. For me any extreme spread that is over 25 FPS is unacceptable no matter how small the group is at 100 yards. Even if I had a load that shot .1 moa at 100 yard yet had an ES of 30, I wouldn’t use that load for a match. I would take a .3 moa load that had a sub 10 fps extreme spread any day of the week because the load will not start to spread vertically past 600.”

http://www.65guys.com/10-round-load-development-ladder-test/
 
ed I use a similar method but just use 3 shot groups for initial testing to find flat spots on my .260 loads. When I go to bullet seating depth I use 5, then when I refine down to primer brand I shoot 10 per brand/type. For my .223 for loads that will not be shot beyond 300 I will no longer bother to chrono. The ES and SD will not matter enough to be worth shooting off a bench for. I much prefer prone
 
LoadKy you can load develop at 100yds just not using an audette ladder approach. See this link: http://www.6mmbr.com/laddertest.html. It recommends 300-500 for stage 2. Dan Newberrys approach of OCW can probably be done at 100. Its goal is to remove flyers and allow for variations in components (powder, primer, brass) and technique without affecting group size. It wont necessarily be the tightest group just the most consistent in theory. There are other approaches as suggested, ed308 is a similar theory to ocw where you find a sweet spot.
 
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LoadKy you can load develop at 100yds just not using an audette ladder approach. See this link: http://www.6mmbr.com/laddertest.html. It recommends 300-500 for stage 2. Dan Newberrys approach of OCW can probably be done at 100. Its goal is to remove flyers and allow for variations in components (powder, primer, brass) and technique without affecting group size. It wont necessarily be the tightest group just the most consistent in theory
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nice article but could you explain what the method in the article does that testing of velocity ES and SD does not do at 100 other than adding in shooter error and environmental factors ?
 
I found it works for me @ 100 yards with my 223.

I fire 5 shot groups @ 100 yards .2 or .3 gr apart starting 2 grains below max. I crony the loads.
Looking at the groups, they sort of make a part or whole sine wave. Pick the lowest group and go from there. It seems the lowest groups have the lowest SD.
Changing primers has moved the powder charge up or down .5 grains for a similar result.

I did this because I had some pull down 4895, now knowing anything more about it.

I was not a believer until I tried it.

David
 
Looking in all the manuals, I figured 25 grains was max for IMR 4895. I then chronographed the loads starting at 23. I did not reach factory published velocity for a 55 grain bullet (3200). I found a sweet spot a little over 3,000 fps and stuck with it. It takes almost 26 grains to get to 3200.

I had 500 Federal MATCH small rifle primers when I did the test.
I ran out and switched to RP small rifle. I re did the test and ended up with 1/2 grain more for same POI, group, and velocity.

I only shoot 100 yards off hand at paper, so Max Velocity was not important as group size.

I loaded the last 1,000 rounds in the 8 lb jug. :(

David
 
ed308 said:
I use 10 shot groups and look for the nodes. It works and saves a lot of time and money. But you'll need a chrony, Magneto Speed or Labradar to track speed.

Here's a summary from the 6.5 Guys website:

I start 1.5 grains below my max load and load 10 shells ascending by .2 gr. So for the Swedemoor, 50.0, .2, .4, .6, .8, 51.0, .2, .4, .6, .8, 52.0.

Then I will shoot these over the chronograph and look for the nodes. A node will be a velocity flat spot where .4-.8 gr of powder doesn’t move the speedometer much. This example with Reloader 26 in my 6.5 Addiction with 140 RDFs, the flat spot is between 51.2 and 51.8 grains -velocity went from 3025-3033 fps. So, .8 grains of powder added a total of 8 fps. Therefore, the middle of my node is 51.5 grains.

Next I then load up 5 of the 51.5 grain load and shoot them over the chronograph and the extreme spread was 5 FPS. I have repeated this with H100V, H4350, 4831, 1000, Retumbo, RE 17,19, 22, 23, 26, wiN 760, 780, VV 160, 170, 560, 570 IMR 4451, 4955, 7828 and 7977. With all of these powders, 3020-3035 fps was an accuracy node without regard to the powder type.

Once I find the velocity node I load in the middle of it then fiddle with COAL until it shoots tiny groups with low low extreme spreads. You can have an accurate load at 100 yards that will not shoot past 600 yards because you have a high extreme spread. For me any extreme spread that is over 25 FPS is unacceptable no matter how small the group is at 100 yards. Even if I had a load that shot .1 moa at 100 yard yet had an ES of 30, I wouldn’t use that load for a match. I would take a .3 moa load that had a sub 10 fps extreme spread any day of the week because the load will not start to spread vertically past 600.”

http://www.65guys.com/10-round-load-development-ladder-test/
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This is both very interesting and totally different from my 6.5 sweed testing. I do not plan to shoot beyond 200. But - this is very interesting (to me) approach. I never heard of a powder charge velocity node. I think I can try and apply some of this to my shooting.

This is a lot of work or a lot of fun, huh? I have only tried 4831. The old guns seem to like the 160RN. Not a long range bullet. Lucky, I dont need that. I may need to try a modern gun from our friends in Finland.
 
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