Satterlee Method advice needed.

[clark33]

I am working up a new load for my 300WSM and tried the Satterlee method. I am using RL26, I loaded in .2 grain increments. Just curious where you guys would start after looking at these results. Is it normal to get lower velocity with higher powder charge this often (or is my scale drifting). Let me know, I have my thoughts on it but would like some input from some guys with more experience than myself. Thanks.

68.0 - 3070
68.2 - 3066
68.4 - 3084
68.6 - 3072
68.8 - 3098
69.0 - 3113
69.2 - 3120
69.4 - 3113
69.6 - 3142
69.8 - 3146

 

[spife7980]

You get the lower speed with a higher charge weight because you have zero clue as to what the actual averages or spread of velocities is for each charge weight, only the snap shot of one round. Its statistically meaningless. I bet if you shot enough of of 68.6 it would average 3090 and enough of 69.4 it would be up around 3130.

So if you are going to go off of a chrono only then you need to pump those sample numbers up


Better would be to look at how they actually shoot instead

 

[Steel head]

I’ve done the satterlee twice.
1st time was easy.
2nd was a bit less conclusive.

I think a satterlee done twice and the results averaged is probably a consistent way to find a good load.

From what I see you have a few options
69.6-69.8 if it’s got some pressure headroom is an obvious area to explore but may be a narrow window.

69-69.4 shows promise.

68-68.2 could be worth exploring if speed is acceptable.

My first choice is 69-69.4

 

[spife7980]

BUt just to graph the lack of data for visual learners

 

[Steel head]

BUt just to graph the lack of data for visual learners
View attachment 7129533

For the cavemen?

 

[Fig]

I'm 100% with spife. I shoot five shots at each load to actually get enough data so I can be comfortable using it. Even that is statistically too small a sample.

 

[spife7980]

For the cavemen?

 

[John Glidewell]

on larger case capacity cartridges I do at least .3 grain spreads. (or .4) The velocity spreads are too close at .2 in larger cases to get real usable data. I also run them twice and graph them both together, maps much better. Below is a sample from a 6.5 I did. You can see the flat spot at 41.9-42.2. 42 was the load for this gun.

 

[Gunfighter14e2]

Many things during the reloading processes can affect muzzle Vol. Not just powder charge weight,...

 

[Temper]

I usually have a pretty good idea of where my charge is going to fall so I tend to load in .1gr increments to find the middle of the node and I do the test twice. If the tests mirror each, I take that to the bank. I redid it once my barrel sped up. This method only really works if you got consistent loading techniques and components. I also confirm my final load velocity over 10 shots and make sure it falls within my 15 ES standard. This method has yet to fail me.

View attachment 7129546

 

[spife7980]

I usually have a pretty good idea of where my charge is going to fall so I tend to load in .1gr increments to find the middle of the node and I do the test twice. If the tests mirror each, I take that to the bank. I redid it once my barrel sped up. This method only really works if you got consistent loading techniques and components. I also confirm my final load velocity over 10 shots and make sure it falls within my 15 ES standard. This method has yet to fail me.
View attachment 7129547 View attachment 7129546

So which did you go for there?

 

[Temper]

36.7 is what I’m loading now. My Chargemaster sometimes drifts upwards .1-.2gr so I like to load towards the bottom end of the node so if it drifts up it wouldn’t knock me off. I got a couple new boxes of brass so that should bring my ES even lower since I currently have 4 different lots with a different number of firings that gave these results.

 

[ditter]

Id say you need at least three strings before you see a flat spot. Then use the average of the three strings to be your MV for each charge. Even if you had an ES of 10, you will likely not see a flat spot if you are doing .2 increments. That's why you have some higher MVs with lower charges.

 

[RegionRat]

Remember, when he (Scott Satterlee) runs his version of the Ladder test, his loading process has been honed by years of experience so that his process isn’t adding dispersion.

If your process isn’t really perfected, and your velocities typically have lots of dispersion, you might miss seeing the nodes altogether.

Best if you can also run the shot-fall target and capture the vertical spread and velocity at the same time. Run the test at as great a distance as you can, and then repeat it to see how many times you need to run before you see a node.

600 yards makes the difference big enough to leverage the step size against the errors due to small samples.

 

[spife7980]

Remember, when he (Scott Satterlee) runs his version of the Ladder test, his loading process has been honed by years of experience so that his process isn’t adding dispersion.

If your process isn’t really perfected, and your velocities typically have lots of dispersion, you might miss seeing the nodes altogether.

Best if you can also run the shot-fall target and capture the vertical spread and velocity at the same time. Run the test at as great a distance as you can, and then repeat it to see how many times you need to run before you see a node.

600 yards makes the difference big enough to leverage the step size against the errors due to small samples.

Exactly. He knows where he wants to be so he just looks for a quick indication of that location in the new barrel. If you don’t have everything nailed down to the t you’re going to have a hell of a time guaranteeing you’re in the good spot with 10 rounds.

 

[RegionRat]

Agree.

I’m sort of a fan of standardization. For example, with a standard WOA service rifle bbl, you don’t have to search far and wide for what works. It has been done so many times you are just trimming a little tweak into the charge or seating depth on the long line loads.

On the other hand, sporting barrels on light weight hunting rifles are a different story. Depending on who does the chamber, the seating depth issues alone are cause for research and load development and the harmonic vibration effects are exaggerated by the light stocks and barrel profiles.

It helps to know how to load for minimizing neck tension variables in all situations. So make sure you have your neck prep down pat. If your velocities are spread as much as the theoretical change from the charge increment, you are going to have to throw many more rounds down range to tease out the node from the noise.

 

[Temper]

Just do a normal ladder....

But finding a load in less than 40 rounds makes me feel good.

 

[kthomas]

Satterlee method is statistically irrelevant, as others have pointed out.

I used to use the so called "Satterlee method", but after years of reloading I ended up finding out that my best so-called velocity nodes were never what you would've picked out from the Satterlee method. It seems convenient and easy, but it certainly doesn't produce the best results.

Shoot two ladders side by side, and most likely you'll get some inconsistencies in so called velocity nodes - they won't match up. I've found this out for loading for 6.5 creedmoor, .300NM and 6BRA.

Best method I've found is to shoot a ladder just to find out relative velocities for charges and where you find pressure. From there, load up a few sets of 5 rounds for some charges that are around the velocity you want to achieve. This will provide the necessary data to get an optimal load.

All my loads have SD's of 5 or less over 10+ shots. Much better than any load I've ever found doing the "Satterlee method".

If my college statistics teacher knew I was using the "Satterlee Method" he probably would have failed me right then and there out of his statistics class.

 

[_Raining]

It doesn't matter how good your loading process is or how well you are sorting, sometimes the powder/bullet combo will just produce shitty SD and you will never know that if you fire just 1 shot. I was getting a SD of 12-15 with RL15 in my 308 using a entris 64-1s scale and a SD of 3-9 with N150 using a chargemaster. Even if you assumed an incredibly low SD (1-2) for every single charge weight, that is still a large enough ES and you will be reading noise not the signal.

 

[Temper]

Are you really going to take a new barrel and develop a load in 20 rounds and take that to a match? Not even going to bother to see if it repeats?

Who said anything about not confirming? Wouldn't do anything until the barrel has sped up anyways.

 

[Temper]

Still got to load ammo and find a safe charge to get the barrel broken in, no? In my case that's been around 150-200 rounds. I'd like to have a decent shooting load instead of just blasting away until it speeds up. My seating depth doesn't change much, just charge weight. I've ordered a new lot of powder and I have 200x virgin brass so I'll be redoing my specific process again and I'll post the results with the confirmation. Will take me a few weeks. Ain't all this part of the fun? I like to see what I can get away with doing/not doing when it comes to reloading and so far I've had good results on three different barrels. As always, YMMV.