156 EOL Load Question

[sean30ber]

6.5-284, 28 inch, Load data on attachment. 40 degrees this morning. Meticulous loading practice. It seems 56.2 is an oddity although 56.8 jumped right back up. Not sure how to read this. Shots 4,5,6 no vertical. Shot 7 not even a bullet width higher. If you take the horizontal out they would have been 1 hole. all other shots were obvious vertical. Ejector mark at 57.1 and Ejector plus slightly heavy bolt lift at 57.4. Any suggestions where to start ?

 

[FEENIX]

6.5-284, 28 inch, Load data on attachment. 40 degrees this morning. Meticulous loading practice. It seems 56.2 is an oddity although 56.8 jumped right back up. Not sure how to read this. Shots 4,5,6 no vertical. Shot 7 not even a bullet width higher. If you take the horizontal out they would have been 1 hole. all other shots were obvious vertical. Ejector mark at 57.1 and Ejector plus slightly heavy bolt lift at 57.4. Any suggestions where to start ?View attachment 321409

Do you have a picture of your actual target? If you have and put the corresponding velocity, it is much easier to analyze than this fancy graph. "I" do not like pressure signs and would drop the charge below 57g, but that's just me. Good luck!

 

[Shane Lindsey]

55.8gr and test seating. You have two that drop lower, which would lead me to believe a scale issue. I get these in the middle and expect that too. If on the higher end, it is pressure.

Would plot these in a data book to add corresponding velocities to where they group as Feenix said to see if it is liking it there or just the velocity. If the barrel won't put it in the same spot, doesn't matter if the velocity is the same.


FWIW I was 2923 FPS with 56.5gr N570 with a 27" tube.

 

[sean30ber]

Attached the photo. I usually drop a full grain and a half from first pressure. That puts this right in the 2917 range.

 

[Shane Lindsey]

What was the Chrono?

 

[sean30ber]

Caldwell, set at 12 feet from muzzle

 

[Beluebow]

How far was this ladder shot?

Based on the target shots 4-5-6 is where you wanna be.

 

[sean30ber]

Shot at 150 to give it a touch of spread.

 

[whirlwindjml]

Like Fenix said. Get back from pressure because summer is coming. I would test between 55.8 and 56 one more time. If it has a spot where the .03 grains isn't really changing speed drastically.you'll probably be in the forgiving spot. Hopefully it will group up for you nicely at the same time.

Is it a fresh barrel? It may well speed up

 

[Dmagna]

Plotting bullets doesn't really mean much unless you are out at about 500. I have shot 1 inch groups with ladder tests and they will scatter out at 500. I would do an OCW test with 55.6-55.9, 2900 is a good speed for a 156. I shoot a 143eldx at 2950 for a 26" proof,

 

[whirlwindjml]

Plotting bullets doesn't really mean much unless you are out at about 500. I have shot 1 inch groups with ladder tests and they will scatter out at 500. I would do an OCW test with 55.6-55.9, 2900 is a good speed for a 156. I shoot a 143eldx at 2950 for a 26" proof,

I agree. I'm looking at velocity vs charge mainly on that chart...

 

[sean30ber]

30 degree difference from this morning. velocity was avg 2940. Best group was 55.8 with an SD - 4.5, ES-11.
3 shot group was .63 at 020., .65 at 010, then went up over 1 inch the further seated I went. Im shooting this 1/4 moa with 140 Hybrids. Id like to get this under 1/2 before ill hunt with it. Really wasnt feeling it this afternoon. My 140 Gold Dots with RS Magnum are 1/3 moa. I think Ill reshoot at -015 -020 -025 another day to see if it was me or the load. If its consistent I might try magnum primers. The SD,ES was nice though.

 

[whirlwindjml]

I been really liking the 156 for accuracy.... You should see what they do at 3200 to a spine though...

 

[sean30ber]

good lord