I know, I know another load development question...Saterlee test

[Lefty Trigger]

This pertains to the Satterlee load development test. Normal test is load work up of .02gr steps looking for "flat spot" in velocity to find node. Here is my question for those that use this method with good results. I ran a test in my 6.5x47 Lapua using a new powder and Sierra 142gr SMK bullets. My load started at 37.4gr and here is my results...
37.4 / 2714
37.6 / 2704
37.8 / 2696
38.0 / 2725
38.2 / 2743
38.4 / 2745
38.6 / 2745
38.8 / 2753
39.0 / 2760
39.2 / 2771
39.4 / 2773
39.6 / 2807

It appears that there is a good node at 38.2 to 38.6,... right? So I loaded up 10 rounds and went back to the range and shot for group which worked out pretty well at 300 yards BUT the speed is not in line with the original test,.. Why?? Actual speed of 10 rounds loaded at 38.4 was 2730.

 

[varget204]

Where temp & wind,altitude the same each time ?

 

[ballison]

IMHO running the Satterlee test with just one round per charge weight can give you some erroneous results. I've been running it with 2-3 per charge weight and averaging them. Its been much more reliable. What were the velocities of the 10 rounds you fired at 38.4gr? Any close to the 2745 you got initially?

 

[Lefty Trigger]

Where temp & wind,altitude the same each time ?

Shot on same day with slight breeze from right to left.

 

[Lefty Trigger]

IMHO running the Satterlee test with just one round per charge weight can give you some erroneous results. I've been running it with 2-3 per charge weight and averaging them. Its been much more reliable. What were the velocities of the 10 rounds you fired at 38.4gr? Any close to the 2745 you got initially?

That would not really save any bullets or powder, which is what the test is supposed to provide. My original method was 3 shot groups on paper looking for a "flat spot" in groups placement but I'm finding this harder to get results with. What seems to be the ideal load seems to fall apart at distance for me, for instance I recently found a load for another rifle that shot a 8 shot one hole group at 200 yards but didn't do so well at 300 yards, still shoots one hole at 200 though. I am curious about what your doing though. While shooting the test your way are you still just watching for numbers or are you also shooting for groups as well, like a two part test??

 

[Coyotefurharvester]

All I have is a 20 something year old chronograph, I have no reason to believe it is anymore accurate or repeatable than the instructions that came with it. So I don't chronograph any single shot loads. I do use the incremental single shot load test to find the minimal vertical dispersion range(hopefully 0.4-0.6 gr). Play with seating depth in the middle of that range, if the load is consistent and meets my accuracy needs, I'm done with load work, while checking for consistency and repeatability is when I chronograph to get an average. Since I'm a hunter and not a br or long range steel banger, my load development(always repeatable 1st shot poi and sub moa groups to 300 yards) may not work for you. This procedure has worked with factory and custom barreled rifles from 17 rem to 338wm for me, including AR's I have assembled. Only difference I see between a factory and custom barrel, custom chambered after market barrels tend to be way less work,time and components to find a "good load".

 

[JFrank]

This pertains to the Satterlee load development test. Normal test is load work up of .02gr steps looking for "flat spot" in velocity to find node. Here is my question for those that use this method with good results. I ran a test in my 6.5x47 Lapua using a new powder and Sierra 142gr SMK bullets. My load started at 37.4gr and here is my results...
37.4 / 2714
37.6 / 2704
37.8 / 2696
38.0 / 2725
38.2 / 2743
38.4 / 2745
38.6 / 2745
38.8 / 2753
39.0 / 2760
39.2 / 2771
39.4 / 2773
39.6 / 2807

It appears that there is a good node at 38.2 to 38.6,... right? So I loaded up 10 rounds and went back to the range and shot for group which worked out pretty well at 300 yards BUT the speed is not in line with the original test,.. Why?? Actual speed of 10 rounds loaded at 38.4 was 2730.

View attachment 1182220

I don’t rely on a chronograph for this test.
I prefer to study the target, with that in mind( since you brought the chrono) tell me about 39.2-39.4

 

[gman47564]

I use this method quiet a bit and have good results usually.. when doing it i have one aim point and watch how they print on paper as well as what the numbers are saying.. i also find the numbers before the flat spot and after the flat spot mean something to.. for instance your test between 38 and 38.2 has 18 fps difference and 38.6 to 38.8 only has 8 fps difference.. i find loading on the end that has the least increase in speed is the side of the flat spot to load on.. so in your case i would try 38.6 , 38.7 and 38.8 in 3 shot groups.. pick the best one and test seating .003 on both sides of what you started with.. one way will shrink the group a little.. then you know which way to go with seating changes.. works for me.. hope it helps ya..

 

[BoydAllen]

I am curious. How did you come up with your seating depth? I usually come up with a powder charge testing with bullets slightly into the lands, and then experiment with seating depth with that charge. Did you use some kind of wind flags, between the bench and target? Generally, I find that testing without flags is a waste of time.

 

[Doom]

What was the velocity, ES, and SD of your 10 shot group?

 

[normmatzen]

I have been using a similar test method to find the optimum charge.
I load 5-5 shot groups with a powder increase of 1% per step. I shoot these groups in round robin fashion (don't even need a target as I only look for Mv).
Then I plot the curve of load vs Es of the data on Excel and do a curve fit to 4-5th polynomial and I get the real curve of the Es.
Then, I tune the tuner at range and I'm good to go.

 

[Lefty Trigger]

I don’t rely on a chronograph for this test.
I prefer to study the target, with that in mind( since you brought the chrono) tell me about 39.2-39.4

Nothing to tell? I assume that area is a higher node but have not done any more testing in that area,... yet.

 

[Lefty Trigger]

I am curious. How did you come up with your seating depth? I usually come up with a powder charge testing with bullets slightly into the lands, and then experiment with seating depth with that charge. Did you use some kind of wind flags, between the bench and target? Generally, I find that testing without flags is a waste of time.

That seating depth is Sierra's COAL for that bullet in the 6.5x47 and it turns out that in my barrel its a .077 jump,... which actually shoots pretty well compared to the .020 I was loading.

 

[Lefty Trigger]

What was the velocity, ES, and SD of your 10 shot group?

The pictured 10 shot group was 2730 velocity and ES was 39 and SD was 12.2 which is not really great. I normally like my SD number less than 10 and it awesome if I get under 5

 

[Doom]

Your ladder shot was 2745 fps for a single shot . Your 10 shot group represents a range of 2706 to 2754 fps for 95% of those shots. Statistically there is no difference.

 

[Texas10]

Many times I've developed a load using the target as the judge, then loaded up some rounds and performed a velocity check only to see every shot (starting with a cold, clean barrel) shoot faster than the previous. The first 7 or 8 will shoot progressively faster, then fall off and then go randomly. For that reason, I'd place no value whatsoever in a single chrono measurement. An average of 5 is the minimum for me.

I typically shoot paper targets at 200 and 300 yds, but also out to 1000 on steel, so I develop the load to shoot a good group on paper, then chrono for a drop chart for long range.

I found the 142 shoots best at .010 jump in my X-Caliber 6.5CM barrel. I shot it at 700 yds last week and the 8 inch target took a real pounding with that load.

 

[Lefty Trigger]

I don’t rely on a chronograph for this test.
I prefer to study the target, with that in mind( since you brought the chrono) tell me about 39.2-39.4

I'm going to test that higher node this Thursday at 300 yards. However since you mentioned studying the target I have another test for you with numbers and this time a labeled target. You are my "go to guy" for reading them and seeing things I never see... lol

This is a Reloder 15 test I ran on my 6mmBR with 107gr Sierras. 200 yards
1) 27.5 2557
2) 27.7 2556
3) 27.9 2588
4) 28.1 2599
5) 28.3 2621
6) 28.5 2651
7) 28.7 2656
8) 28.9 2670
9) 29.1 2693
10) 29.3 2720
11) 29.5 2748
12) 29.7 2741

 

[Dusty Stevens]

No shortcuts to developing your baseline best starting load. I doubt you could get any useful data from a test like this

 

[JFrank]

I'm going to test that higher node this Thursday at 300 yards. However since you mentioned studying the target I have another test for you with numbers and this time a labeled target. You are my "go to guy" for reading them and seeing things I never see... lol

This is a Reloder 15 test I ran on my 6mmBR with 107gr Sierras. 200 yards
1) 27.5 2557
2) 27.7 2556
3) 27.9 2588
4) 28.1 2599
5) 28.3 2621
6) 28.5 2651
7) 28.7 2656
8) 28.9 2670
9) 29.1 2693
10) 29.3 2720
11) 29.5 2748
12) 29.7 2741

View attachment 1182613

Just reading the target I would load between shots 10-11 but for your purposes ( super slow) you may look at shots 1-2

 

[gman47564]

I would load a handfull at 28.8 gr.and see how they shot