147 ELDM in 260 OCW results: Opinion needed

[Kevin1]

IMR 4451 from 39.3 to 42 gr
Lapua new brass
CCI BR2
147 gr ELD M seated with a 0.015 jump and an OAL of 2.870”

100Y shot Robin style , no pressure signs, I haven’t measured any speeds yet ( will do once I settle on a load)

What load would you choose?

 

[supercorndogs]

It is hard to tell the change in POI, because the stickers are all in different places on the grid. Put it up to a window, trace the targets on the back and look at the white side. Or put each sticker exactly the same place in the grid, and shoot it again. It is important to use a target where you can easily identify POI change to run an OCW test.

 

[spife7980]

I'm glad you pointed that out, my brain defaulted to just looking at the groups with the grid as my reference, didn't even notice that the dots were staggered unevenly.

 

[GhengisAhn175]

41.7 seems promising

 

[Kevin1]

I measured the POI shift (both horizontal and vertical) in reference to the center of the dot (point of aim).

Gr	Vertical	Horizontal
39.3	1.68	0.76
39.6	1.42	0.72
39.9	1.7	0.64
40.2	1.41	0.72
40.5	1.47	0.7
40.8	1.38	0.58
41.1	1.09	0.38
41.4	1.14	0.53
41.7	0.89	0.56
42	0.83	0.59

[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i24.photobucket.com\/albums\/c38\/kevin1111\/IMG_06031_zpsmo21ttfz.jpg"}[/IMG2]

 

[Darkside-Six]

looking at that target I would start at 40.8. Depending on what speeds you get you may want to go higher though.

 

[Kevin1]

I think both 40.8 and 41.7 could be a good option.

 

[jsthntn247]

You have 3 nodes in the test. 39.5, 40.6, and 41.8

 

[BurnOut]

Based on that target, I like 40.8. Tweak your scope for POI, and Bob's your uncle. 41.7 looks like another good option.

I do hate shooting at Garland, though... seems like by the time I get settled down and into the zone, it's time for a cease fire... and juuuuuuuust when everyone gets back from hanging targets, you get one more asshat coming out of the office with new targets that he wants to go hang. Dammit.

 

[Kevin1]

Based on that target, I like 40.8. Tweak your scope for POI, and Bob's your uncle. 41.7 looks like another good option.

I do hate shooting at Garland, though... seems like by the time I get settled down and into the zone, it's time for a cease fire... and juuuuuuuust when everyone gets back from hanging targets, you get one more asshat coming out of the office with new targets that he wants to go hang. Dammit.

The good thing about shooting Robin style is that you don't care if you're interrupted by the ceasefire. What I really hate is the loud guns next to me (I'm sure they don't like me either with that LB muzzle break).

 

[Kevin1]

You have 3 nodes in the test. 39.5, 40.6, and 41.8

I like that. I'm going to go with 41.8gr.

 

[jsthntn247]

I like that. I'm going to go with 41.8gr.

Tweak the seating depth some and it should tighten up.

 

[Kevin1]

Tweak the seating depth some and it should tighten up.

This was done with new Lapua brass. I noticed the neck tension was pretty high. I only neck size my brass (with not much tension). I'll play with the seating depth after testing the 41.8 load in the once fire brass. I get the feeling it will be plenty accurate without playing with the seating depth.

 

[Kevin1]

Loaded some rounds with 41.8 gr and shot the below targets
5 shot groups:
100Y : 0.476”
300Y: 2.028” and 2.139”

It’s just ok. I need to play with the seating depth to improve the accuracy.

The chrono for 5 shots:
Average 2695
Hi 2703
Low 2684
Sd 7
ES 19

The first shot was by far the slowest (2684) and that’s what is messing up the ES. The speed is exactly where I want it to be.

What's the next step? Do more or less jump (current jump is 0.015)?


[/URL]

[/URL]

 

[Ayoung1]

I would try a bit more jump going up .005 at a time. I believe the eldm like a small jump, this is going off what I've heard. I just got some 140s to test in my 260.

 

[padom]

Any reason you stopped at 42g? Pressure signs?

My 26" 260rem hammered 140 ELDM with 42.5g H4350. Single Digit ES and SD and velocity was 2855.

 

[Kevin1]

Any reason you stopped at 42g? Pressure signs?

My 26" 260rem hammered 140 ELDM with 42.5g H4350. Single Digit ES and SD and velocity was 2855.

No pressure signs. It seems I have an accuracy node every 1.2gr. After 41.8, my next accuray node would be 43g. I don't want to shorten the barrel rifle (if unnecessary). I'm getting around 2700FPS which is decent IMO.

Do you think it's worthed to do an OCW with higher values (if so which?) or stick with the 41.8gr and reduce the bullet jump?

 

[jsthntn247]

Shoot 3 shot groups from touching the lands to 25 off in .005 increments at 41.8. After you brass is fired you might need to change the powder a .1 or .2 either way to make up for the difference. I run new brass over an expander mandrel to open the necks up some and round them out.

 

[volucris]

I'd get a MagnetoSpeed or LabRadar and take the human error out of it. Sorting by group size isn't going to tell you which load has an ES of 40 or an ES of 11. The load you're testing now may be good, but it might not be the best. Having velocity data for that entire string would be very valuable.

I know it's an old method, but there's better ways for load development than OCW thanks to modern chronographs.

 

[Ayoung1]

Is this a factory barrel or one a smith turned? Mine likes h4350 out of all the preferred powders from this cartridge. Ro16 was a close second but scarce where I'm located. You should work up until you see pressure signs and yet a plateau in velocity. When your I reach the peak velocity and you velocity starts going up in slow increments I'd pick LC the lowest charge weight in that area. From there tweek seating depth until you get low sd and tiny groups.

This is what I recently did with some new bulleta and it worked great.

 

[TripleBull]

Shoot 3 shot groups from touching the lands to 25 off in .005 increments at 41.8. After you brass is fired you might need to change the powder a .1 or .2 either way to make up for the difference. I run new brass over an expander mandrel to open the necks up some and round them out.

I'd be cautious about touching the lands at 41.8 without collecting more data to determine where pressure signs arise. You want to be at least a grain below pressure signs before touching the lands as you will probably get a pressure spike.

 

[Deleted member 10043]

Yep, stay off the lands with that heavy bullet. You should be more interested in maximum speed. Also, it doesn't matter where he put those dots. Each dot is a POA. Max speed, good zero, sub moa, and rock on. I'm also wondering about seating depth importance. I shot some experimental factory 136 grain and was getting .3 five shot groups at less than 2.8 COAL. MV was 2900. 29" barrel on a plain ol' trued R700. Nothing special about the ammo components. Same things we all use.

 

[10ring1]

Don't know what max load is but by the looks of ur data and graph, the ultimate seems to be above 42. If it were me and no pressure signs, I would keep going

 

[supercorndogs]

Yep, stay off the lands with that heavy bullet. You should be more interested in maximum speed. Also, it doesn't matter where he put those dots. Each dot is a POA. Max speed, good zero, sub moa, and rock on. I'm also wondering about seating depth importance. I shot some experimental factory 136 grain and was getting .3 five shot groups at less than 2.8 COAL. MV was 2900. 29" barrel on a plain ol' trued R700. Nothing special about the ammo components. Same things we all use.

Reading the change in POI, is the reason to keep targets consistently on a grid. I guarantee you looked at that target and thought it looked like the POI remained from bottom to top, at first. In other words, if you are telling me, "you can read that OCW test," without the other info provided by the OP. I think you are full of shit.

 

[jsthntn247]

Yep, stay off the lands with that heavy bullet. You should be more interested in maximum speed. Also, it doesn't matter where he put those dots. Each dot is a POA. Max speed, good zero, sub moa, and rock on. I'm also wondering about seating depth importance. I shot some experimental factory 136 grain and was getting .3 five shot groups at less than 2.8 COAL. MV was 2900. 29" barrel on a plain ol' trued R700. Nothing special about the ammo components. Same things we all use.

Hocus pocus, mumbo jumbo bullshit. Touching the lands only increases pressure minimally. He's not seeing pressure now and he's not going to see it touching. I didn't say jam the sum bitches .040 with 10k neck tension. Every Hornady match bullet I've ever loaded for likes to be within .010 of touch. I'll guarantee you his groups get tighter from touch to .010 off at 41.8.

 

[Deleted member 10043]

Hocus pocus, mumbo jumbo bullshit. Touching the lands only increases pressure minimally. He's not seeing pressure now and he's not going to see it touching. I didn't say jam the sum bitches .040 with 10k neck tension. Every Hornady match bullet I've ever loaded for likes to be within .010 of touch. I'll guarantee you his groups get tighter from touch to .010 off at 41.8.

I was shooting .017 off the lands with with 46 grain h4831 and 142 smk. I was getting high pressure signs right up the point the extractor got bent by the shell itself. So, if I was getting consistent .3 groups at 1/8" off the lands I would definitely need to go extremely forward?

 

[Deleted member 10043]

Reading the change in POI, is the reason to keep targets consistently on a grid. I guarantee you looked at that target and thought it looked like the POI remained from bottom to top, at first. In other words, if you are telling me, "you can read that OCW test," without the other info provided by the OP. I think you are full of shit.

What difference does it make where the dots are. And I don't bother with OCW. Just thought it was stupid to complain about it. A dot is a dot and that is what he was aiming at. What a colossal waste of time and resources.

 

[spife7980]

It doesnt make it impossible to interpret, just an unnecessary pain in the ass.

 

[supercorndogs]

What difference does it make where the dots are? And I don't bother with OCW. Just thought it was stupid to complain about it. A dot is a dot and that is what he was aiming at. What a colossal waste of time and resources.

Fixed it for you.

First sentence of that post and my first post answer your question. The way the dots are laid out on the grid makes it look like the POA and POI remain consistent throughout the test. However once the measurements were posted, what would have been obvious if each sticker was in the same place relative to the grid, came to light. And that is exactly why we use target that make it easy to read POI shift, when we run OCW tests.

 

[Deleted member 10043]

Those are 1 inch dots and squares. Plenty of references on that target sheet.

 

[Kevin1]

This is not a factory barrel. It's Bartlein barrel for AIAT chambered by Mile High.

This WE I'll do another OCW with 41.7, 42, 42.3, and 42.6.
Additionally I'll load some 41.8gr with a 0.05 jump to shoot groups at 300Y

Question. Do you think I should go higher than 42.6 for my next OWC?

 

[padom]

This is not a factory barrel. It's Bartlein barrel for AIAT chambered by Mile High.

This WE I'll do another OCW with 41.7, 42, 42.3, and 42.6.
Additionally I'll load some 41.8gr with a 0.05 jump to shoot groups at 300Y

Question. Do you think I should go higher than 42.6 for my next OWC?

You can load as high as you want. You just need to be checking for pressure signs at each charge weight. When you get a heavy bolt lift and/or flattened primers then you can stop and not shoot any higher charge weights in your box. Take them home, pull the bullets and dump the powder. Simple as that. Only you will know how high you can go with your rifle....

 

[Kevin1]

Will do an an OCW from 41.7 to 43.5 with a 0.05 jump.

 

[tpe187]

OCW target in PDF and JPEG. http://practicalrifler.fr.yuku.com/topic/1269/OCW-OFFICIAL-TEST-TARGET#.WUrHmBMrIdV

I normally print these out on card stock paper so I get clean holes vs. tears in the paper. The grid with a consistent POA will normally show you when the barrel is at max whip and then begins moving back. I have found that using a Magnetospeed will change POI, but not change the results and having the velocity gives you an idea if that tight group that happens at a common POI will work or not.

 

[jsthntn247]

Will do an an OCW from 41.7 to 43.5 with a 0.05 jump.

.005 or .050? If .050 your going the wrong way

 

[jsthntn247]

I was shooting .017 off the lands with with 46 grain h4831 and 142 smk. I was getting high pressure signs right up the point the extractor got bent by the shell itself. So, if I was getting consistent .3 groups at 1/8" off the lands I would definitely need to go extremely forward?

If your loading so hot your fucking your gun up, you definitely don't need to be giving anybody reloading advise.

 

[Kevin1]

.005 or .050? If .050 your going the wrong way

Typo error. I meant .005

 

[Deleted member 10043]

46 grains is not too hot seating too close to the lands was the stupid so go skull fuck the butt buddy that recommended it in the first place and don't motherfuck me for pointing out why. That would be you.

EDIT: Toned it down a little.

 

[Kevin1]

Did an OCW from 41.7 to 43.5 with a 0.005 jump.
Don't mind the 5 shot group in the black circle (I was testing some factory 130 ELDM)
It was 97F. Keep in mind that realistically I will only shoot in lower temperatures.

At 43.5gr I saw an ejection mark on one brass.
The next accuracy node seems to be around 42.6-42.9. Given the hot temperature of the day, I think I should go with 42.9gr for my final load. What are your thoughts? [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i24.photobucket.com\/albums\/c38\/kevin1111\/IMG_06221_zpses1y1ldx.jpg"}[/IMG2]

 

[HoustonB77]

Did an OCW from 41.7 to 43.5 with a 0.005 jump.
Don't mind the 5 shot group in the black circle (I was testing some factory 130 ELDM)
It was 97F. Keep in mind that realistically I will only shoot in lower temperatures.

At 43.5gr I saw an ejection mark on one of the round.
The next accuracy node seems to be around 42.6-42.9. Given the hot temperature of the day, I think I should go with 42.9gr for my final load. What are your thoughts?
[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i24.photobucket.com\/albums\/c38\/kevin1111\/IMG_06221_zpses1y1ldx.jpg"}[/IMG2]

42.9 looks good to me. Have you had a chance to chrono the load yet? I would load 10 up at 42.9 and shoot 2 five shot groups. I find that sometimes 3 shot groups can be deceiving.

 

[Kevin1]

I didn't chrono. At 41.8g I was getting around 2700 FPS. I'm expecting around 2850 FPS with 42.9g.

I'm just going to load the 79 remaining brass with 42.9g, do some chrono with 5 of the rounds, then do some 5 shot groups at 100 and 300Y and hit steel with the rest.

 

[Kevin1]

BTW, my initial impression is that this IMR 4451 is as good as the H4350.

 

[Deleted member 10043]

Actually, it was good it was hot that day. You were able to find your max and then back off a little.

 

[HoustonB77]

BTW, my initial impression is that this IMR 4451 is as good as the H4350.

It's good. I have tried both. I'm getting better velocity and lower extreme spreads out of H4350 though. My 260 is a 20 inch.

Sent from my SAMSUNG-SM-G890A using Tapatalk

 

[Kevin1]

That 42.9 gr seems to be a good load.
It shoots in the 0.3s” at 100Y and around 1/2 MOA at 300Y. I’m sure it can do better. It was pretty windy and the mirage was pretty bad. I just couldn’t get a clear sight picture of those 2” targets at 300Y.

Chrono numbers:
Average 2784 fps
SD 8
ES 24

Here’s a pic of both 100 and 300Y.
5 shot groups, prone.

[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i24.photobucket.com\/albums\/c38\/kevin1111\/42.9_zpsngdwqmq6.jpg"}[/IMG2]

 

[Kevin1]

It's good. I have tried both. I'm getting better velocity and lower extreme spreads out of H4350 though. My 260 is a 20 inch.

Sent from my SAMSUNG-SM-G890A using Tapatalk

You must be right.
I was out shooting today. It was hot. I had some issues with the POI, so did a chrono. Average speed 2819, SD 21, ES 59. Not impressed by that SD.
It was very accurate though. I was getting 0.25" to 0.3" at 100Y for 5 shot groups and was able to easily hit steel at 1100Y (granted it was a 2moa size target).

 

[Deleted member 10043]

What sort of POI problems?

 

[Kevin1]

What sort of POI problems?

The bullet was hitting too high. I wasn't sure if it was the mirage or a change in MV. So I did a chrono. There was an increase in MV and the ES/SD were pretty bad compared to before. Can the increase in MV be because the barrel is pretty new (250 rounds down the tube when I did the last chrono).

 

[HoustonB77]

The bullet was hitting too high. I wasn't sure if it was the mirage or a change in MV. So I did a chrono. There was an increase in MV and the ES/SD were pretty bad compared to before. Can the increase in MV be because the barrel is pretty new (250 rounds down the tube when I did the last chrono).

Yes your barrel may have sped up a little bit. I got about 50 FPS more velocity at 500 rounds than I did when it was new.