Armory Sponsor
Posted: 5/31/2011 8:55:17 PM EDT
When doing a ladder test do you test say 15 different loads from low to high and see where the closest loads end up? Then do further testing on those? I searched but couldn't find anything. Here's what I had planned on doing unless I'm way off and someone corrects me.
.223 rem/ 75 BTHP. 1 round at each charge with Varget. 20.9 21.1 21.3 21.5 21.7 21.9 22.1 22.3 22.5 22.7 22.9 23.1 23.3 23.5 |
|
I read somewhere to do it that way. I guess when the bullet goes where you want it you're done ?
I load 10 of each, either .3 or .4 apart and shoot 10 shot groups and pick the best of those Keep in mind, I don't know what I am doing, but I did use my Giraud today 
|
|
http://optimalchargeweight.embarqspace.com/
When you see the vertical nodes, pick the fastest one that makes you happy. Then you start in that range with the other variables. Neck tension with brass cycles and temperature/altitude would be some of the "other" variables to test. Assuming of course that you have all your brass prep under control first. The idea is to see where the most "forgiving" node exists for a recipe and then examine things like seating depth and the above to see if the node breaks down. In the best case, you find a zone where you can go from hot to cold, new brass to old, and still get away with it.... |
|
This. I have only used this a few times Andrew just trying random charges. It works well. They key is consistency in your reloading, and a well rested rifle.
Quoted:
http://optimalchargeweight.embarqspace.com/ When you see the vertical nodes, pick the fastest one that makes you happy. Then you start in that range with the other variables. Neck tension with brass cycles and temperature/altitude would be some of the "other" variables to test. Assuming of course that you have all your brass prep under control first. The idea is to see where the most "forgiving" node exists for a recipe and then examine things like seating depth and the above to see if the node breaks down. In the best case, you find a zone where you can go from hot to cold, new brass to old, and still get away with it.... Posted Via AR15.Com Mobile |
|
That is what i do when i start a new load. i start at the low charge and load 6 rounds of each
weight increasing by .3 grains each time. Then i shoot them at a 100 yds and don't mess with the scope keep the same point of aim at each target –– i use a diff. target for each powder weight and lable them. when done you will see some loads that group best i then take that load and load 10 of it again and load in .1gn above and below 10 each and see how they shoot. here is one of mine don't know if i am right but it works for me. WIN 748 LADDER |
|
Ladder test is the way to go: I vary by .2 or .3 grains, shots of 6 or 8. I prefer more than 5 shots each group because I am still in the beginner stage of precision shooting and I feel that *I* remain the greatest variable in how well my rifle shoots. Thus, the odds of me pulling a shot here and there are high; I prefer to have a few more rounds on target for the sake of "averaging" out my mistakes versus those of the rounds loaded.
I would recommend fouling the bore with standard ammo first (and make sure you're on paper at least). Also, limit your total number of shots/groups - shooter fatigue will wind up being a far greater variable depending on your skill, pace and the weather, etc. I usually can only do four groups of 6-8 before I start opening up, but I don't get to practice often so your mileage may vary. Shots of less than five or more than eight rounds each are very likely a waste of time and resources IMHO - specifically for less skilled shooters as I mentioned above. Shooting 15 rounds with each having a different powder charge (!) is missing the point of ladder testing: you want the most consistent charge, not the charge that comes closest to hitting whatever your scope is focused on that day. You do this by worrying about the size of the group of 6-8 shots itself, not how far away from your point-of-aim the group is.... Pro Tip: once you find the load your rifle likes (ie is the most consistent), then you re-adjust the scope! 
Lastly, do not get hung up on velocity or max loads, as you will against waste your time. A few dozen feet-per-second variance is worthless if you can't hit your target each and every time. I say this, because when I first started loading I found that the maximum velocity was cool and sexy! but then I realized a really fast projectile doesn't look cool if you can't consistently hit your targets with a $1500 rifle, hand-loaded ammo and an audience.
Your mileage may vary - I have my own method as do most people here, but this is another reference to incorporate into your experimentation. This link has a very nice explanation |
|
Bump 'cuz I'm fixing to try this on my next range trip. I'm a little confused, as it seems as there are a couple different methods being discussed here.
On one hand, there's firing one shot each of increasing charge weights all at the same target and finding a "node" where shots come together. This seems to be what the OP in this thread was going for. On the other hand, there's the method from the article, where three shots from each charge weight are fired in sequence, with one target for each charge weight. So if you have 6 increments, you have 6 targets, and each ends up with three shots on it (all of the same charge weight) and you find your nodes by measuring where the 3-shot groups are in relation to the point of aim. You fire a shot from group 1 at target 1, then one from 2 at target 2, on through 6 and then back to the start again, until all shots are fired. Am I on track with these two variations? The first method seems to be more efficient in terms of time and components, but does it really give good results? |
|
IMHO, this is an excellent and thorough explanation of "ladder testing". It is also posted in the the reloading section of Sniper's Hide along with a series of discussion posts (questions and answers).
Note that he is a precision shooter (and trainer), so he is teaching to eek out every little bit of accuracy (consistency). In the left margin, you'll see other articles starting with brass prep and going through concentricity / neck turning. Know that most reloaders don't need to get into everything he's teaching to meet their needs, but again, the ladder testing explanation is very helpful to all. |
|
Quoted:
IMHO, this is an excellent and thorough explanation of "ladder testing". It is also posted in the the reloading section of Sniper's Hide along with a series of discussion posts (questions and answers). Note that he is a precision shooter (and trainer), so he is teaching to eek out every little bit of accuracy (consistency). In the left margin, you'll see other articles starting with brass prep and going through concentricity / neck turning. Know that most reloaders don't need to get into everything he's teaching to meet their needs, but again, the ladder testing explanation is very helpful to all. I wish I had done it this way to begin with. I have shot 100 rounds now and still dont have a load worked up for my AR. Back to square one... I hate load development! 
|
|
Quoted:
Bump 'cuz I'm fixing to try this on my next range trip. I'm a little confused, as it seems as there are a couple different methods being discussed here. On one hand, there's firing one shot each of increasing charge weights all at the same target and finding a "node" where shots come together. This seems to be what the OP in this thread was going for. On the other hand, there's the method from the article, where three shots from each charge weight are fired in sequence, with one target for each charge weight. So if you have 6 increments, you have 6 targets, and each ends up with three shots on it (all of the same charge weight) and you find your nodes by measuring where the 3-shot groups are in relation to the point of aim. You fire a shot from group 1 at target 1, then one from 2 at target 2, on through 6 and then back to the start again, until all shots are fired. Am I on track with these two variations? The first method seems to be more efficient in terms of time and components, but does it really give good results? Eric, yes that is the process. Make sure you cover all increments from the minimum to maximum so you don't miss any nodes. For each target determine the center of the poi. You're looking for two or more consecutive targets where the centers of the poi are very close to the same. Then you pick a charge weight inbetween and fine tune by +/- .1 gr. and adjusting your seating depth. Sometimes the targets can be pretty hard to interpret. |
Armory Sponsor