Need Help Interpreting Load Data

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#1
Hi,
Now that I have some data the next step is what the heck do I do with it? I’ll say up front that I am not the world’s greatest shooter so I toyed with the idea of throwing out 1 flyer in each group? I’m here to learn and don’t take things too personally so any help appreciated. Where would you go from here?

P.s. Apologies upfront if this is in the wrong thread.

Brass: Hornady
Bullet: Hornady 178 BTHP Match
Primer: Federal 210
Powder: Hodgdon VARGET
Distance: 100 Yards
Chronograph: LabRadar
C.O.L. 2.9390”
Bullet Seating Depth: 2.2760”
Rifle: Cadex Kraken
Caliber: .308 Winchester
Case Length: 2.0045”
Headspace: 1.6250”
Barrel Length: 24”
Twist: 1-11.25”

Temperature: 64F
Humidity: 91%
Wind: 10 mph SSW
Elevation: 307’
DNR=Did Not Record (chronograph did not pick up)

String #1 35.0 gr.
Shot 1: 2087
Shot 2: 2185
Shot 3: DNR
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2087
Max. Velocity: 2185
Avg. Velocity: 2136
S.D.: 69.1
E.S.: 98

String #2 37.1 gr.
Shot 1: 2282
Shot 2: 2268
Shot 3: 2280
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2268
Max. Velocity: 2282
Avg. Velocity: 2277
S.D.: 7.7
E.S.: 14

String #3 39.2 gr.
Shot 1: 2397
Shot 2: 2381
Shot 3: 2369
Shot 4: 2314
Shot 5: 2382
Min Velocity.: 2314
Max. Velocity: 2397
Avg. Velocity: 2369
S.D.: 32.2
E.S.: 83

String #4 41.3 gr.
Shot 1: 2514
Shot 2: 2495
Shot 3: 2526
Shot 4: 2500
Shot 5: DNR
Min Velocity.: 2495
Max. Velocity: 2526
Avg. Velocity: 2509
S.D.: 14
E.S.: 31

String #5 42.4 gr.
Shot 1: 2564
Shot 2: 2555
Shot 3: 2572
Shot 4: 2568
Shot 5: 2567
Min Velocity.: 2555
Max. Velocity: 2572
Avg. Velocity: 2565
S.D.: 6.5
E.S.: 17 Target.jpg
 

Subwrx300

Sergeant of the Hide
Jan 15, 2014
607
252
63
Cedar Springs, MI
#2
Well the difficult part of this test and data is that the charge increments are very large. If you didn't see signs of pressure at the max charge you shot (42.4 if I'm not mistaken), you should reshoot 41gr -42.4 at an interval of .3gr (41, 41.3, 41.6, 41.9 and 42.2; maybe add 42.4 as control). Shoot them with chrono just like you did above but on a wider flat Target with all aim points on same horizontal line like this:
IMG_20180718_225126.jpg

That will show you the relative impact point as charge increases. Your looking for a flat spot in terms of elevation and windage point of impact (like 41.8-42 above).

You should have better data after doing above. Repost the new test and we can help further if needed.
 

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#3
Hi Sub, Thanks for taking a look. I had already shot another series before I saw your post and think I may have at least come close to what you had suggested. I think this is starting to make some sense to me, if you look below I'm guessing 42.2 may be the ticket? Or is it 41.7 because of the low ES?

P.s. I was having a few chrono issues that day .

Brass: Hornady
Bullet: Hornady 178 BTHP Match
Primer: Federal 210
Powder: Hodgdon VARGET
Distance: 100 Yards
Chronograph: LabRadar
C.O.L. 2.9390”
Bullet Seating Depth: 2.2760”
Rifle: Cadex Kraken
Caliber: .308 Winchester
Case Length: 2.0045”
Headspace: 1.6250”
Barrel Length: 24”
Twist: 1-11.25”

Temperature: 57F
Humidity: 63%
Wind: 10 mph NE
Elevation: 307’
DNR=Did Not Record (chronograph did not pick up)

String #1 41.5 gr.
Shot 1: 2533
Shot 2: DNR
Shot 3: DNR
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2533
Max. Velocity: 2533
Avg. Velocity: 2533
S.D.: -
E.S.: -

String #2 41.7 gr.
Shot 1: 2524
Shot 2: 2527
Shot 3: 22526
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2524
Max. Velocity: 2527
Avg. Velocity: 2526
S.D.: 2
E.S.: 2.1

String #3 42.0 gr.
Shot 1: 2529
Shot 2: 2519
Shot 3: 2547
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2519
Max. Velocity: 2547
Avg. Velocity: 2532
S.D.: 28
E.S.: 14.3

String #4 42.2 gr.
Shot 1: 2588
Shot 2: 2549
Shot 3: 2558
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2549
Max. Velocity: 2588
Avg. Velocity: 2565
S.D.: 38
E.S.: 20

String #5 42.4 gr.
Shot 1: 2568
Shot 2: 2588
Shot 3: 2566
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2566
Max. Velocity: 2588
Avg. Velocity: 2574
S.D.: 22
E.S.: 12.2

Scan.jpg
 

Subwrx300

Sergeant of the Hide
Jan 15, 2014
607
252
63
Cedar Springs, MI
#4
Hi Sub, Thanks for taking a look. I had already shot another series before I saw your post and think I may have at least come close to what you had suggested. I think this is starting to make some sense to me, if you look below I'm guessing 42.2 may be the ticket? Or is it 41.7 because of the low ES?

P.s. I was having a few chrono issues that day .

Brass: Hornady
Bullet: Hornady 178 BTHP Match
Primer: Federal 210
Powder: Hodgdon VARGET
Distance: 100 Yards
Chronograph: LabRadar
C.O.L. 2.9390”
Bullet Seating Depth: 2.2760”
Rifle: Cadex Kraken
Caliber: .308 Winchester
Case Length: 2.0045”
Headspace: 1.6250”
Barrel Length: 24”
Twist: 1-11.25”

Temperature: 57F
Humidity: 63%
Wind: 10 mph NE
Elevation: 307’
DNR=Did Not Record (chronograph did not pick up)

String #1 41.5 gr.
Shot 1: 2533
Shot 2: DNR
Shot 3: DNR
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2533
Max. Velocity: 2533
Avg. Velocity: 2533
S.D.: -
E.S.: -

String #2 41.7 gr.
Shot 1: 2524
Shot 2: 2527
Shot 3: 22526
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2524
Max. Velocity: 2527
Avg. Velocity: 2526
S.D.: 2
E.S.: 2.1

String #3 42.0 gr.
Shot 1: 2529
Shot 2: 2519
Shot 3: 2547
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2519
Max. Velocity: 2547
Avg. Velocity: 2532
S.D.: 28
E.S.: 14.3

String #4 42.2 gr.
Shot 1: 2588
Shot 2: 2549
Shot 3: 2558
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2549
Max. Velocity: 2588
Avg. Velocity: 2565
S.D.: 38
E.S.: 20

String #5 42.4 gr.
Shot 1: 2568
Shot 2: 2588
Shot 3: 2566
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2566
Max. Velocity: 2588
Avg. Velocity: 2574
S.D.: 22
E.S.: 12.2

View attachment 6954730
I would suggest trying .1 intervals on between 41.7 and 42.1. The impact points on target are virtually identical and speed is nearly same avg between the groups.

Find the best from that series and run seating depth test at .10-15 intervals from where you are now. I think you will find one that shoots lights out.

It looks like somewhere around 41.8/9 will be good and then adjust seating depth to bring it tighter.
 

Skookum

Flattus Domini
May 6, 2017
835
729
93
Your mom's
#5
Hi Sub, Thanks for taking a look. I had already shot another series before I saw your post and think I may have at least come close to what you had suggested. I think this is starting to make some sense to me, if you look below I'm guessing 42.2 may be the ticket? Or is it 41.7 because of the low ES?

P.s. I was having a few chrono issues that day .

Brass: Hornady
Bullet: Hornady 178 BTHP Match
Primer: Federal 210
Powder: Hodgdon VARGET
Distance: 100 Yards
Chronograph: LabRadar
C.O.L. 2.9390”
Bullet Seating Depth: 2.2760”
Rifle: Cadex Kraken
Caliber: .308 Winchester
Case Length: 2.0045”
Headspace: 1.6250”
Barrel Length: 24”
Twist: 1-11.25”

Temperature: 57F
Humidity: 63%
Wind: 10 mph NE
Elevation: 307’
DNR=Did Not Record (chronograph did not pick up)

String #1 41.5 gr.
Shot 1: 2533
Shot 2: DNR
Shot 3: DNR
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2533
Max. Velocity: 2533
Avg. Velocity: 2533
S.D.: -
E.S.: -

String #2 41.7 gr.
Shot 1: 2524
Shot 2: 2527
Shot 3: 22526
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2524
Max. Velocity: 2527
Avg. Velocity: 2526
S.D.: 2
E.S.: 2.1

String #3 42.0 gr.
Shot 1: 2529
Shot 2: 2519
Shot 3: 2547
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2519
Max. Velocity: 2547
Avg. Velocity: 2532
S.D.: 28
E.S.: 14.3

String #4 42.2 gr.
Shot 1: 2588
Shot 2: 2549
Shot 3: 2558
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2549
Max. Velocity: 2588
Avg. Velocity: 2565
S.D.: 38
E.S.: 20

String #5 42.4 gr.
Shot 1: 2568
Shot 2: 2588
Shot 3: 2566
Shot 4: DNR
Shot 5: DNR
Min Velocity.: 2566
Max. Velocity: 2588
Avg. Velocity: 2574
S.D.: 22
E.S.: 12.2

View attachment 6954730
Is there a particular reason you are running these so slow?
 

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#6
I would suggest trying .1 intervals on between 41.7 and 42.1. The impact points on target are virtually identical and speed is nearly same avg between the groups.

Find the best from that series and run seating depth test at .10-15 intervals from where you are now. I think you will find one that shoots lights out.

It looks like somewhere around 41.8/9 will be good and then adjust seating depth to bring it tighter.
Excellent; I may not get out for a few days (crappy weather) but I will run it exactly as you described using, 41.7, 41.8, 41.9, 42.0 and 42.1. Once I have that quick question on seating depth, when you say adjust at .10-.15 increments is that out (closer to lands) or in (farther from lands)?
 

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#7
Is there a particular reason you are running these so slow?
Hi Skook,

No, other than I am new to reloading and using the Hornady 10th edition as guide. They listed 42.4 as Max Load, so although I went to 42.4 I wasn't sure I needed to try and go beyond as I think I was seeing what I wanted at less than the Max Load. My goal was to shoot .5 MOA or better with as low an ES as possible. I'm going to run another 5 strings using the suggestion above and see how that looks.
 

Skookum

Flattus Domini
May 6, 2017
835
729
93
Your mom's
#8
Hi Skook,

No, other than I am new to reloading and using the Hornady 10th edition as guide. They listed 42.4 as Max Load, so although I went to 42.4 I wasn't sure I needed to try and go beyond as I think I was seeing what I wanted at less than the Max Load. My goal was to shoot .5 MOA or better with as low an ES as possible. I'm going to run another 5 strings using the suggestion above and see how that looks.
The books are a guide to be heeded to be sure, but your chrono will give you the most relevent feed back for your particular rifle and load combo.

To get low SD's, the powder typically needs to reach the optimal pressure range. Out of your 24" barrel, these should be safely and sanely running 2650fps or so in the optimal pressure range. It is true that there is usually a low node at the bottom, or just off the bottom of the optimal pressure. Federal Gold Medal Match is an example of a factory load that does this. It makes it very forgiving for many different rifles but it also makes it slow.

If you continued your testing up to at least say, 43.5 or 43.7 grains, It's my guess you would find a good spot. Then fine tune seating depth from there.
 
Likes: Subwrx300

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#9
The books are a guide to be heeded to be sure, but your chrono will give you the most relevent feed back for your particular rifle and load combo.

To get low SD's, the powder typically needs to reach the optimal pressure range. Out of your 24" barrel, these should be safely and sanely running 2650fps or so in the optimal pressure range. It is true that there is usually a low node at the bottom, or just off the bottom of the optimal pressure. Federal Gold Medal Match is an example of a factory load that does this. It makes it very forgiving for many different rifles but it also makes it slow.

If you continued your testing up to at least say, 43.5 or 43.7 grains, It's my guess you would find a good spot. Then fine tune seating depth from there.
1. I am having fun (Important)
2. I enjoy Shooting (Very Important)
3. I love to learn (Most Important)

I will run both scenarios, the one suggested by Subwrx300 and the one you are suggesting, I think it will prove interesting. So, for this I will run 5 strings at:

42.9 (starting a 1/2 grain up from where I ended which showed no signs at all of over pressure), 43.1, 43.3, 43.5 and 43.7 to see what that looks like as well (checking carefully for signs of over pressure as I go)

I probably won't get back out until next week but will post results from both test as soon as I have them.
 

Strykervet

Resident Phoenix Eye and Dim Mak Instructor
Jun 5, 2011
2,791
944
113
42
Pierce County, WA
#11
In addition to shooting groups in the string like Subwrx300 says, I'd also do it two more times at least, ideally on a couple different days. And make sure the weapon is secured well using whatever you have available. Sandbags are great. The less it moves the more accurate your data will be. If you have real rest to lock it in, use that. The more consistent and stable the better the data. This way you'll know you're groups are as tight as can be, and you'll have repeated it a couple times to ensure any one group isn't an anomaly.

I use a similar load, new Lapua brass, CCI34's, 175SMK's, 41.8gr. RE15 in an SR25. It'll be the once fired brass that'll get reworked to find the best possible load.
 

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#12
I got a chance to test another set today (41.7, 41.8, 41.9, 42.0 and 42.1). I think for sure that as the charge goes up my groups start to tighten (at least that’s what I think I see). All of the targets were at the same elevation and I was shooting from a bipod with a rear bag for support. I’ll keep this a little simpler unless I’m leaving out the most important parts:
41.7
Min Velocity.: 2497
Max. Velocity: 2515
Avg. Velocity: 2505
S.D.: 8.98
E.S.: 18

41.8


Min Velocity.: 2497
Max. Velocity: 2537
Avg. Velocity: 2522
S.D.: 16.34
E.S.: 40

41.9

Min Velocity.: 2500
Max. Velocity: 2535
Avg. Velocity: 2524
S.D.: 13.94
E.S.: 35

42.0

Min Velocity.: 2516
Max. Velocity: 2540
Avg. Velocity: 2525
S.D.: 10.41
E.S.: 24

42.1

Min Velocity.: 2525
Max. Velocity: 2545
Avg. Velocity: 2536
S.D.: 8.7
E.S.: 20

Unfortunately my time this week is a little limited but I think Thursday or Friday this week I will be able to run: 42.9, 43.1, 43.3, 43.5 and 43.7. Then I think (hope) it will all start falling into place for me. Thanks!

P.s. Sorry about the zero but I didn’t want to start fiddling with the scope after I started. 15OCT2018_1.jpg 15OCT2018_2.jpg
 

Subwrx300

Sergeant of the Hide
Jan 15, 2014
607
252
63
Cedar Springs, MI
#13
Well from current targets, I think 42 or 42.1 is your load. You could always continue to test for higher node and see when you get pressure signs. I wouldn't worry about the flyer. It looks a bit like something is happening with your form or consistency during each group as most of the other groups have a high right/low left appearance also. Maybe not but overall looks pretty good.

From here a seating depth test could certainly tighten things up considerably.

But the nice aspect about 42.1 is the group is starting to drop a bit lower than 42.0. This means that if a charge is a tiny bit light (say .1 grain) it will launch slightly higher than normal to make up for the lower velocity and at some point downrange will still hit the same point of impact as 42.1.

This "convergence" is something I try to tune into my loads if I can't find a node that is flat POI on both sides +-.1gr of best load.
 

powerspc

Sergeant of the Hide
Mar 15, 2018
160
100
43
#14
Well from current targets, I think 42 or 42.1 is your load. You could always continue to test for higher node and see when you get pressure signs. I wouldn't worry about the flyer. It looks a bit like something is happening with your form or consistency during each group as most of the other groups have a high right/low left appearance also. Maybe not but overall looks pretty good.

From here a seating depth test could certainly tighten things up considerably.

But the nice aspect about 42.1 is the group is starting to drop a bit lower than 42.0. This means that if a charge is a tiny bit light (say .1 grain) it will launch slightly higher than normal to make up for the lower velocity and at some point downrange will still hit the same point of impact as 42.1.

This "convergence" is something I try to tune into my loads if I can't find a node that is flat POI on both sides +-.1gr of best load.
First, I greatly appreciate the help and analysis; 42.1 would have been my guess as well. No doubt there are some form issues which I am working through at the same time as I am forced to shoot weak hand, non-dominant eye due to some issues with my dominant eye. I'm definitely getting more comfortable doing so.

I think I will try to test for a higher node since I'm still in the learning phase (and will always be I guess) to see what that tells us, I will post that later this week hopefully. Once I have that I can start playing with the seating depth and then have a least a rudimentary understanding of how to do load development from initial selection of brass, primer, powder and bullet to selecting a final charge weight and seating depth. Thanks again.
 
Likes: Subwrx300
Top Bottom