Magnetospeed came loose, need advice on my next step?

[eod_tek]

Ill start by saying that I am very new to reloading and this is my first load development. I used the search function but still have a question.
I loaded up a test at 20 thousandths off the lands, started at 80.6 grains, and loaded in .2 increments up to 83.2 (14 rounds). I was very diligent about checking my magnetospeed between the first 8-10 rounds, but it never shifted and I got complacent. on shot 12, 82.8 grains, I saw a drop in velocity I wasn't exactly expecting, and checked the magnetospeed and it had shifted forward about 1/2-1 inch. I fixed it and shot rounds 13 and 14. Of course, upon reviewing the data, the graph between 82.6 and 83.2 was almost dead flat, except for that 82.8 grain shot where the chrono was loose.
My goal is to load a conservative (not in a hurry to chase max loads) and consistent load between 2850-2950.

Knowing that the magnetospeed was loose on shot 12, am I best to load up those last 4 rounds again and reshoot it, or is having the data I have about shots 10, 13 and 14, and knowing it was loose on that shot enough to invalidate it and peruse that as a node? And finally, is there any reason not to load up some rounds at the lower node (around 81 grains) which is in my goal velocity and seems stable, and disregard the potential upper node at 83-83.2? Any advice would be greatly appreciated!
Data from the days shooting:

Velocity	CW
2857	80.6
2894	80.8
2902	81
2896	81.2
2908	81.4
2905	81.6
2918	81.8
2920	82
2936	82.2
2922	82.4
2949	82.6
2934	82.8
2950	83
2950	83.2

My setup:
300 Norma Magnum
26" 1:9 Proof Carbon Fiber
230 rounds on the barrel
H1000
Lapua Brass
225 ELD Match
FED215M
Magnetospeed v3

 

[GIXXER2000]

Here is my load for my 300NM
30 in Bartlein 1-8 twist barrel for mt AI-PSR long action. I have 125 rounds on the barrel as of today 1/6/23

1st
Brass Norma Brass
Primer 215M
Powder 86.2 N568
Bullet 230 Berger Hy
SD 4.1
AVG FPS 2839 ( 10 shot average)

2nd
Brass Norma Brass
Primer 215M
Powder 86.2 N568
Bullet 230 A-Tip
SD 7.2
AVG FPS 2945 (10 shot average)

 

[straightshooter1]

Ill start by saying that I am very new to reloading and this is my first load development. I used the search function but still have a question.
I loaded up a test at 20 thousandths off the lands, started at 80.6 grains, and loaded in .2 increments up to 83.2 (14 rounds). I was very diligent about checking my magnetospeed between the first 8-10 rounds, but it never shifted and I got complacent. on shot 12, 82.8 grains, I saw a drop in velocity I wasn't exactly expecting, and checked the magnetospeed and it had shifted forward about 1/2-1 inch. I fixed it and shot rounds 13 and 14. Of course, upon reviewing the data, the graph between 82.6 and 83.2 was almost dead flat, except for that 82.8 grain shot where the chrono was loose.
My goal is to load a conservative (not in a hurry to chase max loads) and consistent load between 2850-2950.

Knowing that the magnetospeed was loose on shot 12, am I best to load up those last 4 rounds again and reshoot it, or is having the data I have about shots 10, 13 and 14, and knowing it was loose on that shot enough to invalidate it and peruse that as a node? And finally, is there any reason not to load up some rounds at the lower node (around 81 grains) which is in my goal velocity and seems stable, and disregard the potential upper node at 83-83.2? Any advice would be greatly appreciated!
Data from the days shooting:

Velocity	CW
2857	80.6
2894	80.8
2902	81
2896	81.2
2908	81.4
2905	81.6
2918	81.8
2920	82
2936	82.2
2922	82.4
2949	82.6
2934	82.8
2950	83
2950	83.2

My setup:
300 Norma Magnum
26" 1:9 Proof Carbon Fiber
230 rounds on the barrel
H1000
Lapua Brass
225 ELD Match
FED215M
Magnetospeed v3

When one is after consistency, this kind of ladder is a waist of time. If you were to shoot this ladder again, you'd very very likely get very different results . . . as did Brian Litz in his testing (see pic below). You're much better off evaluating your consistency by what you get on paper.

 

[D1gger]

Everybody has their own way of load development, but if you step back and look at this, you are increasing your load by .2 on an 80 grain load. You are making a .25% change in each step. Like straightshooter said, if you did this again, you would probably have different results.
That being said, if that was my data, I would probably look at 82, and see how it shoots groups, what your SD's and ES's are. In the end, if I get a few loads with single digit SDs, I usually pick the load with better groups.
I get lazy too, and if my powder dispenser likes 81.8 better than 82, I'll go with 81.8.

 

[Doom]

Ill start by saying that I am very new to reloading and this is my first load development. I used the search function but still have a question.
I loaded up a test at 20 thousandths off the lands, started at 80.6 grains, and loaded in .2 increments up to 83.2 (14 rounds). I was very diligent about checking my magnetospeed between the first 8-10 rounds, but it never shifted and I got complacent. on shot 12, 82.8 grains, I saw a drop in velocity I wasn't exactly expecting, and checked the magnetospeed and it had shifted forward about 1/2-1 inch. I fixed it and shot rounds 13 and 14. Of course, upon reviewing the data, the graph between 82.6 and 83.2 was almost dead flat, except for that 82.8 grain shot where the chrono was loose.
My goal is to load a conservative (not in a hurry to chase max loads) and consistent load between 2850-2950.

Knowing that the magnetospeed was loose on shot 12, am I best to load up those last 4 rounds again and reshoot it, or is having the data I have about shots 10, 13 and 14, and knowing it was loose on that shot enough to invalidate it and peruse that as a node? And finally, is there any reason not to load up some rounds at the lower node (around 81 grains) which is in my goal velocity and seems stable, and disregard the potential upper node at 83-83.2? Any advice would be greatly appreciated!
Data from the days shooting:

Velocity	CW
2857	80.6
2894	80.8
2902	81
2896	81.2
2908	81.4
2905	81.6
2918	81.8
2920	82
2936	82.2
2922	82.4
2949	82.6
2934	82.8
2950	83
2950	83.2

My setup:
300 Norma Magnum
26" 1:9 Proof Carbon Fiber
230 rounds on the barrel
H1000
Lapua Brass
225 ELD Match
FED215M
Magnetospeed v3

What @straightshooter1 said!

A little background here since you mention you are new to reloading. Scott Satterlee was the origin of the "flat spot" reload development. Scott is an excellent shooter and competitor and knows the ins and outs of reloading. I am sure he happened upon a tested flat spot and tried that load and developed a load based on it. So he assumed that the flat spot was real and began to use and it worked. However, as of about a year ago, he no longer used that method. He had switched to picking a load and working on seating depth. The reality is there is no theory that would would explain adding powder and getting true less or equal velocity. In your case the 0.2 gr of increment is going to result in about 7 fps of velocity change due to powder charge. Your chronograph accuracy is +/- 3 fps so detecting a true change is problematic at best. It's highly likely that differences in other components are creating the flat spots that show up.

There is a lot of evidence today that nodes don't exist. This seems to be especially true of heavy barreled rifles used in long range 1000yd and greater. As for powder nodes, in terms of statistical performance there is no real explanation for the idea or theory that one one load would display a statistical superiority over an incrementally different load. What is becoming understood is that the data that has been generated, especially in regard to standard deviation of velocity has not been properly analyzed and is based on insufficient data. Also, looking at velocity is collecting data on one aspect of the accuracy/precision of the rifle as a system. I haven't checked today, but the last time I was at the range the target didn't need a chronograph to know where the bullet impacted and it was the final arbiter of precision. Since you brought up the Satterlee approach you might find the video below interesting. It's part of a series of three if I remember correctly.



(Watch the whole video. A note here, he didn't look for pressure here because he has experience with the brass/bullet/powder combination and knew this was a safe load)

I do not use his method but the method I use relies solely on target data and I have never needed a chronograph to develop accurate loads. What the chronograph can tell you is the quality/consistency and velocity of your reloads.

I will mention one other aspect of reloading. You need to set a realistic goal for the load you develop based on what the rifle will be used for. Do you need 1 MOA or 0.5 MOA? Do you need a minimum velocity? Do you need the load to be accurate over a wide range of conditions? Setting these will give you a realistic (hopefully) goal. Simply reloading and looking for the lowest standard deviation or tightest group is an open ended quest akin to searching for Unicorns.

 

[OkieMike]

I've had very good results with the ladder test in .223/5.56 loads. I can usually get a good sweet spot.

Bigger calibers... Not as much. I guess I got "lucky" a few times but not enough to depend on it. But it does give me a pretty good STOP HERE indicator when looking for pressure... So in that regard it's still useful. And it will give a ballpark to look at if I have a rough idea of a velocity I'm looking for.

But for my .308 and .300 WM I have found it's hard to beat 3 shot groups in incremental charges... Find the one that groups the tightest and then play with seating depth to see if I can tighten it up more.

Just my experience.

Mike

 

[straightshooter1]

I do not use his method but the method I use relies solely on target data and I have never needed a chronograph to develop accurate loads. What the chronograph can tell you is the quality/consistency and velocity of your reloads.

Likewise, I rely on my chrono to tell me how well I'm loading my cartridges and for that, I look for low SD's along with low ES's. I don't look for low SD's and ES's to tell me what kind of accuracy or precision I'll get on paper as one can have those with low number, yet poor results on paper. Though, I do see that ES's are particularly important for long range shooting, and one has to shoot several shots of the same load to get an ES to tell you anything about that load.

Some competitive shooter's, like Erik Cortina, say they start with looking for low ES's and once they find a load that's giving a low ES (single digits or low teens), then they look to their paper results working on seating depths. To get those low ES's, one needs to pay a lot of attention to various details of one's loading process since things like neck tension and primer powder combinations can make all the difference.

Before all the above, it really starts with good barrel and one that's mounted properly. If you don't have that, then the load development won't help much. A good action and trigger helps too.

. . . gotta have realistic view of what you have to work with and what you're objectives are.

 

[eod_tek]

Great advice from everybody so far, thank you! Some follow up:

Loaded up some three shot groups and went back out today because the weather wasnt awful. Shots are all at 100 yards.

1st group was at 81gr (it was actually 5 shots, I had two more I loaded up to warm up the barrel/make sure my magnetospeed was reading (I used the wiser precision mount today to keep it off the barrel)).
Results:
1.33" (I know I threw the last one, I rushed the trigger pull because the wind was picking up fast, if I eliminated that 5th shot its a .87")
SD: 6.7
ES: 19
Average Velocity 2894

2nd group was 82 grains
1.01"
SD/ES inconclusive because this magentospeed hates me

3rd group was 83.1 grains
.246"
SD: 9.6
ES: 19
Average Velocity 2956

Judging by todays results, that 83.1 grains is the load Im going to stick with and try shooting for a large shot count group.

Also, for context I shot the 82.8 again and it was indeed 2931 vs 2934 that I got yesterday, so the magentospeed moving did not effect the actual measured velocity.

 

[Doom]

Great advice from everybody so far, thank you! Some follow up:

Loaded up some three shot groups and went back out today because the weather wasnt awful. Shots are all at 100 yards.

1st group was at 81gr (it was actually 5 shots, I had two more I loaded up to warm up the barrel/make sure my magnetospeed was reading (I used the wiser precision mount today to keep it off the barrel)).
Results:
1.33" (I know I threw the last one, I rushed the trigger pull because the wind was picking up fast, if I eliminated that 5th shot its a .87")
SD: 6.7
ES: 19
Average Velocity 2894
View attachment 8040907

2nd group was 82 grains
1.01"
SD/ES inconclusive because this magentospeed hates me
View attachment 8040908
3rd group was 83.1 grains
.246"
SD: 9.6
ES: 19
Average Velocity 2956
View attachment 8040910

Judging by todays results, that 83.1 grains is the load Im going to stick with and try shooting for a large shot count group.

Also, for context I shot the 82.8 again and it was indeed 2931 vs 2934 that I got yesterday, so the magentospeed moving did not effect the actual measured velocity.

Since you included some shot data I'll try and give you a little perspective on what that data means. First and foremost your intent in taking data (samples) is to try and predict what future rounds will be based on those samples. Based on your data and sample sizes we can conclude the following:

81 gr
Average Velocity 2894. First, your five shot average (mean) velocity means that if you tested an infinite number of 3 shot groups of this load 95% of the means would fall between 2885.7 to 2902.3 fps.

SD: 6.7 The standard deviation of 6.7 forgive shots means that if you tested an infinite number of 5 shot groups of this load 95% of the standard deviations would fall between 4 and 19.3 fps.

ES: 19 Yor ES of 19 doesn't really tell you much. ES will always be made up of only two shots whether it's from a 3 shot group or a 1000 shot group. In ua three shot group the two values that make up ES represent 67% of the data in the SD. In a 1000 shot group they represent o.2%. In reality as the number of shots in a test goes up the SD and ES both increase but the ES grows much more than the SD.

83.1 gr

Average Velocity 2956 Your three shot average (mean) velocity means that if you tested an infinite number of 3 shot groups of this load 95% of the means would fall between 2932.2 and 2980 fps.

SD: 9.6 SD The standard deviation of 9.6 for three shots means that if you tested an infinite number of 3 shot groups of this load 95% of the standard deviations would fall between 5 and 60.3 fps.

ES: 19. Same as 81 gr.

 

[straightshooter1]

Doom makes an excellent point about ES being only a measurement between either two velocities of a set or two shots on a target. Because it's really only measuring two shots and ignoring all the rest, I found that it's best to focus on the Mean Average to help me interpret what's better or worse.

Below is a target test where I loaded up 50 rounds, all being loaded the same (a cartridge and load that tends to work well for me), and proceeded to see what improvement I might be able to make with some seating depth changes. After every 3 shots I'd seat the bullet .003" deeper. Sometimes I'd shoot one more than 3 shots just to be sure I'm delivering a good shot group. After I get home I run this through my OnTarget Precision Calculator app that measures the groups and calculates the Mean Average and give me a good idea where that center of the group is. To me, it looks like a seating depth .018"- .021" deeper than where I started is the place I want to be.