Ladder test vs ladder test.FAIL - Rifle needs help.

Correct me if I am wrong, but you are using a hunting scope on that rifle, which most likely does not feature a parallax adjustment. Like most hunting scopes, its parallax correction is likely set at 100 yards. If, for whatever reason, your eye is not exactly aligned with the center axis of your scope, when you shoot at 250 yards, the POI will vary. Since this is the second Wby Vanguard and third barrel with which you experience those issues, and your 100 yard groups are good, may I suggest that you look into using a scope that features a variable parallax distance adjustment (aka side focus) and set it at 250 yards.
 
pacobillie said:
Correct me if I am wrong, but you are using a hunting scope on that rifle, which most likely does not feature a parallax adjustment. Like most hunting scopes, its parallax correction is likely set at 100 yards. If, for whatever reason, your eye is not exactly aligned with the center axis of your scope, when you shoot at 250 yards, the POI will vary. Since this is the second Wby Vanguard and third barrel with which you experience those issues, and your 100 yard groups are good, may I suggest that you look into using a scope that features a variable parallax distance adjustment (aka side focus) and set it at 250 yards.
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See post 48.
 
I find ladder tests are next to useless. No, let me rephrase that. I find they are completely useless. There simply isn't enough data.As I said, they are useless..... Now flame away.......
 
Canuck525 said:
I find ladder tests are next to useless. No, let me rephrase that. I find they are completely useless. There simply isn't enough data.As I said, they are useless..... Now flame away.......
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Irrelevant to this issue , as well I've done group tests after my ladders as well as a group test just listed here with factory premium ammo.

If a ladder at 250 yards has the variances I've been showing then there is something sideways.
 
I may be new to reloading, but I do know a thing or two about design of experiments.
The main problem with your ladder test is lack of replicates. Beside the load itself, the shooter, the gun/optics, environmental conditions, etc. all bring a certain amount of variance, and with one shot per load it is impossible to tell if the difference (or lack thereof) between loads X and Y is true difference or a statistical fluke.

Four or more shots (replicates) per data point are way more informative:

dCJyQyt.jpg


This was all done at the same COAL, the next step would be to select the best charge weight and repeat the test with various seating depths. I think 38.8 or 38.9 should work, and then if Dillon throws +/- 0.1 variance, it should not have a major effect.
 
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5,45, I like these tests much better. Nice job.
Try 38.6,7,8,9 an 39.
4 each for 20 rounds. Pick the middle of your node.
Then seating depth test at 0.003" increments. Pick the middle of your second node.
All tests on the same paper you have been using to see trends. Do the seating depth tests at 200 or 300 if weather permits. Easy to find the seating node and pick the middle.

39.2 and 38.4 both impact different than 38.8, so you don't want to focus on those, just close to them to narrow up your selection in the middle. I usually do powder jumps by .3 grains instead of .4 to help narrow it up a bit. Did you get a fps ES on any of those?
 
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Lead hammer said:
5,45, I like these tests much better. Nice job.
Try 38.6,7,8,9 an 39.
4 each for 20 rounds. Pick the middle of your node.
Then seating depth test at 0.003" increments. Pick the middle of your second node.
All tests on the same paper you have been using to see trends. Do the seating depth tests at 200 or 300 if weather permits. Easy to find the seating node and pick the middle.

39.2 and 38.4 both impact different than 38.8, so you don't want to focus on those, just close to them to narrow up your selection in the middle. I usually do powder jumps by .3 grains instead of .4 to help narrow it up a bit. Did you get a fps ES on any of those?
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It was the first attempt ever :) I did 0.4 increments to cover the entire charge range from the loading manual with a reasonable number of test points. Don't have a chrono yet. Just eyeballing it, the difference between 38.8 and 39.2 is negligible and 38.4 is close. I should probably reserve some time to measure the hits, feed the data to R and run proper stats. Another test with 0.2-0.3 increments and chrono might be helpful too.

Our range is 100m max, but there is another one nearby that goes up to 1200.
 
5.45 hit the nail on the head and is the reason I do not use ladder tests. There simply isn't enough reliable data.It's a complete waste of barrel life in my opinion.
 
5.45 said:
It was the first attempt ever :) I did 0.4 increments to cover the entire charge range from the loading manual with a reasonable number of test points. Don't have a chrono yet. Just eyeballing it, the difference between 38.8 and 39.2 is negligible and 38.4 is close. I should probably reserve some time to measure the hits, feed the data to R and run proper stats. Another test with 0.2-0.3 increments and chrono might be helpful too.

Our range is 100m max, but there is another one nearby that goes up to 1200.
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The difference from the center of both those groups is a 1/2” different. Take that out to distance and you won’t like it. It’s all about the vertical, get it bang on.
 
I see your ladder playing with powder charges but have you done a berger style seating depth test to start with? Take your 180sgk and do a seating depth test with a medium charge. After firing around 100 ladder tests in the last couple years I now start with a seating depth test first, pick the best from that and run powder ladder test. Pick the nodes and finetune seating depth. The seating depth is more of a course accuracy adjustment, without getting that at least close a ladder on paper is not really readable.

You should be getting some more consistent results from a good barrel. If everythig else is in place with the rifle and you have done seating depth testing and then ladders have the barrel spun off and checked.
 
Important: randomize the shots!
Instead of shooting load A1, A2, A3, A4, then load B1, B2 and so on, use a random number generator or a pair of dice to draw the shooting sequence. It should be C2, A4, B1 etc in no particular order.
Doing so will minimize the confounding effects of barrel heating up, shooter's fatigue, changing environmental conditions (e.g. wind picking up).
 
5.45 said:
Important: randomize the shots!
Instead of shooting load A1, A2, A3, A4, then load B1, B2 and so on, use a random number generator or a pair of dice to draw the shooting sequence. It should be C2, A4, B1 etc in no particular order.
Doing so will minimize the confounding effects of barrel heating up, shooter's fatigue, changing environmental conditions (e.g. wind picking up).
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I sense some Sarcasm in this post ! lol RJ
 
LongBomber said:
I see your ladder playing with powder charges but have you done a berger style seating depth test to start with? Take your 180sgk and do a seating depth test with a medium charge. After firing around 100 ladder tests in the last couple years I now start with a seating depth test first, pick the best from that and run powder ladder test. Pick the nodes and finetune seating depth. The seating depth is more of a course accuracy adjustment, without getting that at least close a ladder on paper is not really readable.

You should be getting some more consistent results from a good barrel. If everythig else is in place with the rifle and you have done seating depth testing and then ladders have the barrel spun off and checked.
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Not really a jump sensitive bullet with an Rt/R of 0.90 but I agree and have been starting with seating depth tests as well, even though Bryan Litz states the test is only really for VLD type bullets.
 
Took the rifle out with the changes.Re-did the bedding , tried a pressure point as well as switching out the stock.All group tests.Some factory ammo some hand loads.

Still No dice.

Federal GMM with fixed stock and 180 SGK, no pressure point



Same everything , with pressure point...



I switched out the stocks...

GMM , SGK 180 and 190 LRAB....



And again...



It's going to see someone now.I can go no further.
 
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