Long range load development at 100 yards.

[memo43]

Will do and once again thanks for sharing the knowledge.

 

[Erik Cortina]

I recently did a ladder test for my .308 savage axis and went with a powder range to test that guys on here suggested to try. I shot three rounds each from 42.1 to 43.3gr in 0.3gr increments using your method Mr. Cortina. This is what it did. I feel like the big wide groups were results of something I was doing differently every shot, or it could have been a dirty barrel? Do you suggest shooting this again and trying to get better results before determining what charge to go with? I am using Varget powder, 165gr hornady sst bullets, 210m primers. seating depth is 2.260" to the ogive. I know it is touching the lands but I'm not positive as to how much of a jam it is.

Here is my method, I do not do ladder tests.
http://forum.accurateshooter.com/index.php?topic=3814361.msg36221455#msg36221455

 

[L1986]

Erik,
Was wandering if you could take a look at my targets at the bottom of page 103 and let me know what you think. Thank you sir! I really appreciate you helping us all out!!

 

[Erik Cortina]

Erik,
Was wandering if you could take a look at my targets at the bottom of page 103 and let me know what you think. Thank you sir! I really appreciate you helping us all out!!

Do you have any chronograph readings? The groups are very inconsistent.

What rifle are you using? Tell us more about it.

 

[L1986]

Erik,
Was wandering if you could take a look at my targets at the bottom of page 103 and let me know what you think. Thank you sir! I really appreciate you helping us all out!!

Do you have any chronograph readings? The groups are very inconsistent.

What rifle are you using? Tell us more about it.

I do have chrono readings but I'll have to post them later. The rifle is described in the post above the target pics but it's a savage action with a McGowan 22-250ai barrel.

 

[x_wolf]

I post it also here. Maybe someone can judge my target:

I followed Erik´s advice to load development ( http://forum.accurateshooter.com/index.php?topic=3814361.0 ). This is the first part of it. Bullet seated at jam and -0.20" and loads with 0.5gr increments. Please tell me - do you see any node there? I think something between load Nr. 17 and 18 would be interesting. Yes there is always a flyer, but i think i know the reasons for it - mirage and my bad trigger pull. So, by loads Nr. 17 and 18 there are always first 2 shots in one hole and third shots were my errors.

Click the link below for bigger preview.

http://img.janforman.com/100mNormaGoldenTarget130gr2015419dax0.jpg

 

[jsthntn247]

I recently did a ladder test for my .308 savage axis and went with a powder range to test that guys on here suggested to try. I shot three rounds each from 42.1 to 43.3gr in 0.3gr increments using your method Mr. Cortina. This is what it did. I feel like the big wide groups were results of something I was doing differently every shot, or it could have been a dirty barrel? Do you suggest shooting this again and trying to get better results before determining what charge to go with? I am using Varget powder, 165gr hornady sst bullets, 210m primers. seating depth is 2.260" to the ogive. I know it is touching the lands but I'm not positive as to how much of a jam it is.

Keep going up with powder, you shouldn't reach pressure till 45-46 grains.

 

[Erik Cortina]

I post it also here. Maybe someone can judge my target:

I followed Erik´s advice to load development ( http://forum.accurateshooter.com/index.php?topic=3814361.0 ). This is the first part of it. Bullet seated at jam and -0.20" and loads with 0.5gr increments. Please tell me - do you see any node there? I think something between load Nr. 17 and 18 would be interesting. Yes there is always a flyer, but i think i know the reasons for it - mirage and my bad trigger pull. So, by loads Nr. 17 and 18 there are always first 2 shots in one hole and third shots were my errors.

Click the link below for bigger preview.

http://img.janforman.com/100mNormaGoldenTarget130gr2015419dax0.jpg

Try between 17 and 18.
How do you know the third shots were errors?

 

[x_wolf]

I always saw first two hits in same hole. Then by third shot I was able to recognize stronger mirage. This maked me little bit nervous and the point of aim wasn't perfect. Result was also not proper trigger pull (still waiting for the Jewell trigger...) This was relevant to these two groups (17 and 18). Weather was changing bit faster and causing this problem... Maybe it sounds like justification but I was trying my best. When I saw the one hole of first 2 shots by Nr. 17 and 18 I said to myself "...That's it...." and then came this damn mirage.

OK, thank you Erik, I was hoping for loads Nr. 17 and 18. I'll advance to the next step.

 

[fspitzdorf]

Ran the test on my fresh (15 rounds through it) 1941 USMC Sniper clone last Saturday. Ran them through OnTarget and this is what I got... (sorry no chrono numbers for this one either.)

Criterion 1:10 - 1903 Springfield Profile
168 SMK
IMR 4350
CCI BR 2
LC NM 62 Case

Vertical distance to aim point (as given by OnTarget) for each group was -

53.0 ~ -1.260
53.5 ~ -0.296
54.0 ~ 0.198
54.5 ~ 0.448
55.0 ~ 1.571
55.5 ~ 1.570
56.0 ~ 1.800
56.5 ~ 1.865
57.0 ~ 1.922
57.5 ~ 1.792

 

[Erik Cortina]

fspitzdorf, I like 56.5 and 57.0

 

[fspitzdorf]

Erik,

Can you expound a bit on why?

Thanks,

Jamie

 

[Erik Cortina]

Erik,

Can you expound a bit on why?

Thanks,

Jamie

Because they impacted the same distance away from the aim point vertically, except for one shot. If you had chronograph numbers it would be much easier to find the node, but since you don't, this is the best guess I can come up with as to where the node is.

 

[bill123]

Erik,
I was hoping for your input on this target. I am shooting a GAP 6.5 SAUM, 26" 8.7 twist barrel. 140 Berger Hybrids, .020" jump w/ H-1000 & unfired Norma brass. I have about 75 rounds through the barrel. From what I understand, the goal w/ this bullet is 3100 fps after 100-200 rounds through the barrel. I'm figuring that with a new barrel, I should be looking for about 3000fps. I did an initial velocity work-up and got the following velocities (only one round per charge):
60.0gr: 2953
60.5: 2986
61.0: 2986
62.0: 3054
62.5: 3061
I'm thinking either 60.4 or 62.2 as a starting point. I realize that its not optimal to do this with unfired brass but that's all I had. I'm looking for a place to start.
Thanks,
Bill

 

[Erik Cortina]

Erik,
I was hoping for your input on this target. I am shooting a GAP 6.5 SAUM, 26" 8.7 twist barrel. 140 Berger Hybrids, .020" jump w/ H-1000 & unfired Norma brass. I have about 75 rounds through the barrel. From what I understand, the goal w/ this bullet is 3100 fps after 100-200 rounds through the barrel. I'm figuring that with a new barrel, I should be looking for about 3000fps. I did an initial velocity work-up and got the following velocities (only one round per charge):
60.0gr: 2953
60.5: 2986
61.0: 2986
62.0: 3054
62.5: 3061
I'm thinking either 60.4 or 62.2 as a starting point. I realize that its not optimal to do this with unfired brass but that's all I had. I'm looking for a place to start.
Thanks,
Bill

Start at 60.0
I don't believe in the "target speed" theory, I believe in doing a detailed load work up and selecting the load that provides the most consistent speeds and accuracy. Accuracy first, speed second (assuming you will be supersonic at the range you intend to shoot at).

 

[bill123]

Thanks for the reply. Can you explain what you mean by start at 60.0?

 

[Erik Cortina]

Thanks for the reply. Can you explain what you mean by start at 60.0?

I thought you were asking for a starting point to do powder test again with fireformed brass. Why did you only get velocity for one shot on each charge?

 

[bill123]

Thanks for the reply. Can you explain what you mean by start at 60.0?

I thought you were asking for a starting point to do powder test again with fireformed brass. Why did you only get velocity for one shot on each charge?

Sorry for the confusion. My plan was to do a pressure work up first (shooting 1 round in increasing .5gr increments) to find what GAP considered a good MV range. That was my first shooting session (target not posted). The target that I posted was an OCW round robin based on the idea that I would test around 3000fps. That session was 3 shots per .3gr increment. For the posted target, I am trying to discern which charge I should work with.

 

[Erik Cortina]

Thanks for the reply. Can you explain what you mean by start at 60.0?

I thought you were asking for a starting point to do powder test again with fireformed brass. Why did you only get velocity for one shot on each charge?

Sorry for the confusion. My plan was to do a pressure work up first (shooting 1 round in increasing .5gr increments) to find what GAP considered a good MV range. That was my first shooting session (target not posted). The target that I posted was an OCW round robin based on the idea that I would test around 3000fps. That session was 3 shots per .3gr increment. For the posted target, I am trying to discern which charge I should work with.

Shoot groups until you encounter pressure signs. You will be able to tell where your node is. Use a chronograph when you test.

 

[bill123]

Will do. Thanks