Range Report Ocw test help

[jb41291]

Today I ran an ocw test from 41.4 to 42.2 in .2gr increments. This test was based off my ocw test from last week in .4 increments from 39.0 to 42.6. Below is the link from my original post and a picture of today's test. Let me know what you all think. Personally, i was just going to load 41.8 and run a seating depth test.

Original post:

https://www.snipershide.com/shooting/threads/ocw-test-help.6943363/

Today's test:

 

[eklarsen]

42 is better but i find it odd that 41.8 and 42.2 are so different. When I do it I shoot one round of each load through the different targets then repeat to eliminate shooter bias. you should get a clear pattern. I would bet that anything from 41.9 through 42.2 are very close but then do seating test to fine tune.

 

[jb41291]

42 is better but i find it odd that 41.8 and 42.2 are so different. When I do it I shoot one round of each load through the different targets then repeat to eliminate shooter bias. you should get a clear pattern. I would bet that anything from 41.9 through 42.2 are very close but then do seating test to fine tune.

Thanks for the reply! I wanna say that was me causing that slight shift. Mirage was really bad at the range today. But 41.8 and 42.2 look almost identical pattern wise.

 

[ShtrRdy]

I would use 42.0 for my next step.

 

[Snuby642]

42.0 looks gtg by far.
Imho

 

[jb41291]

@Snuby642 @ShtrRdy
Should i just call it good and keep them .020 off the lands? Just confirm consistency and start cranking em out?

 

[garandman]

My take.....

0.4 gr increments are pretty big, but 42.0 looks good.

I'm guessing this is 100 y, so I'd call it good, and load 'em up.

 

[Snuby642]

I would keep that powder charge the 42gr and try a few seating depth changes if not constricted by magazine or cannelure.

I'm not a jam it in the lands guy but some bullets react well to that "perfect" jump and others don't care much it seems to me.

 

[jb41291]

My take.....

0.4 gr increments are pretty big, but 42.0 looks good.

I'm guessing this is 100 y, so I'd call it good, and load 'em up.

Yes. Thank you for your input.

 

[jb41291]

I would keep that powder charge the 42gr and try a few seating depth changes if not constricted by magazine or cannelure.

I'm not a jam it in the lands guy but some bullets react well to that "perfect" jump and others don't care much it seems to me.

I am using 6.5 130 gr elm. Do you have any suggestions for seating depth increments?

 

[Snuby642]

No sir .
New to 6.5
Shooting hornady 123 sst for break in and brass.
Can't wait to get another can adapter and dies, case checker.

6.5g so limited to case capacity and cannelure for me.

If a bolt gun I would sneak up in 0.005 thousands increment and see what it did to groups.

Still breaking it in.

 

[jb41291]

Finally got to do a ocw test for my tempest.

Shot round robin with 5 rounds in each target. Well, attempted to. Targets 4, 5, and 6 are short one round each due to light primer strikes. From the looks of it either target 5 or 8 are my scatter nodes. Based on ocw test guidance of scatter nodes being 1.5% up or down from a ocw, if i go with target 5 my ocw would be either 41.7 gr for or 42.9 gr. If i go with target 8 as my scatter my ocw would be 42.6 gr or 43.8 gr.

Even considered 41.1 gr on target 1 to be the scatter node as its spread and pattern are unique from all the others. Going above it would bring me to 41.7 gr.

I am thinking of using 41.7 gr as my ocw. Let me know what you think or recommend. Still learning to read ocw results. Any feedback is appreciated. Thanks!

 

[ShtrRdy]

I like where targets 2 and 3 ended up.

 

[jb41291]

I like where targets 2 and 3 ended up.

I agree. I ended up settling on 41.6 gr fir the rest of my testing.

 

[RustyNutz48]

I’m interested where your load settled at. Also, curious if you have any velocity numbers to support those charge weights. 42.0 looks good but may be on the perimeter of the node.
Looks like you’re on the right track

 

[iceng]

42.0gr. do 5 shot groups of 41.9, 42.0 and 42.1 to confirm its in a nice area.

Proceed to seating depth. Do 2 shot seating on each depth. Sure you can do 5 and make it nicer, however I've found doing smaller increment, and shoot more frequently you can watch the group close up. If you do 10thou seat differences, I find that a bit tough.

Good luck, post results.

 

[Snuby642]

41.7 and 42.0 look good so why not split the difference to allow for temperature swings and powder drop margin?

 

[jb41291]

I’m interested where your load settled at. Also, curious if you have any velocity numbers to support those charge weights. 42.0 looks good but may be on the perimeter of the node.
Looks like you’re on the right track

I agrer with this statement as well. Its comforting knowing i am on the same page as others haha. I am going to get velocity after seating depth. Not too concerned with trying to get high numbers but consistency instead

 

[XLR308]

This was over two years ago i would hope you have settled on a load by now unless youve been on deployment or in a coma.

 

[jb41291]

This was over two years ago i would hope you have settled on a load by now unless youve been on deployment or in a coma.

we are talking about my most recent load development with my newer rifle.

 

[XLR308]

we are talking about my most recent load development with my newer rifle.

Still running the 130eldm ?

 

[jb41291]

Still running the 130eldm ?

Yes sir

 

[XLR308]

Yes sir

I havent ever been able to get my hands on any but exclusively run 130AR Hybrids and 140 hybrids.
If you have enough rounds through your Tempest to accomodate for speed up i agree the 41.7 load looks like the best place to start tweeking seating depth.

 

[jb41291]

Did seating depth. Shot in prone I am a little out of practice so please excuse the sloppiness of my groups. I believe any change in point of impact was due to mirage coming off the berms preceding the 100 yard line. I am thinking group 6 (2.165" CBTO) for my OSD. What do you all think?

CBTO increments of .005"
F) 2.170"
1) 2.190"
2) 2.185"
3) 2.180" (Group size: .92")
4) 2.175"
5) 2.170"
6) 2.165"
7) 2.160"

 

[RustyNutz48]

Good notes on your testing, easy to interpret. For what it’s worth, here’s my .02

Couple things for consideration:
- Retest 5,6,7,8: 2.155 at 2-300 yds (identify the OSD’s spectrum).
- Do your best to mitigate your variables (mirage and breaking clean shots) or increase your sampling size to 7 shots each
- Barrow a chrono if possible. Much easier interpreting oddities when each shot has a value.

Thanks for sharing and letting us tag along with your load development.