Looking for some advise on my ladder test

slvdout

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Hey guys, I shot these today and was looking for a little input. I'm shooting a 142 SMK out of my 6.6X284. I started with 45.5gs of H4831sc and went up in 1/2g increments to 49.5 with no pressure signs. I did two tests, 1 at 200m and another at 300m with the same loads. Looks to me like I have a node at #7,8,9 on both targets and another at #2 and 3. What do you guy's think? Where would you go from here?
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Ladder test at short distances really don't tell anything. IMO having done a few myself at theses distances. I just shoot 5 shot groups 2 or 3 hundred meters and look at the vertical dispersion instead.

However if I were to choose a range to do additional work a load base on your ladder test I would choose 5 and 6 on your 300m target because between those two loads they are dead flat.
 
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Ignore the guy above.
The ladder test is a great method to develop a load with minimal shots.
200m is a good distance for it. Any distance you don't get a ragged hole at is a good one.
So, based on this method, load #8 is the load you have found.
You can confirm it by shooting a 5 hole group at 200 or 300 and be done with it.
 
If I was to start at load 7 and work up to load 9 in say .2 grain increments. Would it be worth it to shoot 3 shot groups or should I shoot 5?
 
If I was to start at load 7 and work up to load 9 in say .2 grain increments. Would it be worth it to shoot 3 shot groups or should I shoot 5?

According to all I've read and tested, you're done, you found your load.
If you want to try to shrink the group some more, play with the bullet ogive seating off lands. No guarantees there.
By the way, that 7-8-9 group looks like a 0.3MOA center to center. That's so incredibly good!
Zero the rifle on #8 and let us know what a 5 shot group looks like.
 
let me explain myself: the reason for 5 shot groups is to check the thermal wandering of the barrel.
Shoot at least 2 groups.
 
According to all I've read and tested, you're done, you found your load.
If you want to try to shrink the group some more, play with the bullet ogive seating off lands. No guarantees there.
By the way, that 7-8-9 group looks like a 0.3MOA center to center. That's so incredibly good!
Zero the rifle on #8 and let us know what a 5 shot group looks like.

Ok thanks for the help. I'll try a couple 5 shot groups and see what happens.
 
ladder tests are a great way to find the node faster then groups, but as mentioned the further you push out the more they will tell you.. assuming your lines are 1" apart, your 200m target shows just over a 1/2 moa spread for all shots.. while showing you have a lot of potential accuracy, it doesnt tell u Fuk all about your nodes...

FWIW , i even do my 223 ladders at min 400,

if you look at your 2nd pic, shots 2/3, 5/6, 7-9, all look like nodes... typically a barrel will have 2 , not 3, (just a generalization ) so go back and look at pic1 shot6 is 1/4 Moa higher then 5. But at 300 they are dead level.. So that can't be it .. Now start comparing how all the other shots are .. 2/3, and 7-9 are the only ones that are consistant in where they land within the spread between the 2 pics

personally i would explore the 7-9 and push out even further, no point in running a 6.5-284 if youre not after velocity.
 
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Ignore the guy above.
The ladder test is a great method to develop a load with minimal shots.
200m is a good distance for it. Any distance you don't get a ragged hole at is a good one.
So, based on this method, load #8 is the load you have found.
You can confirm it by shooting a 5 hole group at 200 or 300 and be done with it.

According to all I've read and tested, you're done, you found your load.
If you want to try to shrink the group some more, play with the bullet ogive seating off lands. No guarantees there.
By the way, that 7-8-9 group looks like a 0.3MOA center to center. That's so incredibly good!
Zero the rifle on #8 and let us know what a 5 shot group looks like.

Look I'm not hear to start a pissing match but a lot a people read and really don't understand and REALLY READ what a ladder test instructions are. I never said ladder testing is not a good way to find a node, to clarify ladder testing is not as effective in finding vertical dispersion at shorter rangers due to various factor (IE. not being exaggerated enough). Ladder test are up to subjective interpretation. Yours or mine is just an interpretation and shouldn't be treated any less. Why should my interpretation be ignored? Am I wrong when I said that those single SHOTS produce the least vertical? Why did you zero on #8? Does #8 in itself prove that the vertical is the least of all the single shots? Yes your looking for an accuracy window but the name of the game when it come to ladder testing is vertical.

I quote "This similarity in point of impact between sequential shots (looking only at vertical separation and ignoring horizontal POI shifts due to wind) will reveal a powder charge range that should shoot to nearly the same POI independent of velocity differences." http://www.6mmbr.com/laddertest.html

Ultimate Monkey has made some good recommendations if velocity is what you're after.
 
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From the Sierra Manual:
Accuracy Load: IMR-4831/ 46.7grs. 2800fps/ 2437ft. lbs.
Hunting Load: RE-19/ 48.1grs. 2900fps/ 2615ft. lbs.

48.2 grains of H4831SC is supposed to give 2800 fps so you may have found something very close with your loads 7, 8 and 9.

You are now ready to try 5 of each of those loads but your gun may like being loaded to the nuts and #9 may be your ticket.
You have room to experiment.

Further to 308BAR's comments, there are more ways to do ladder testing and interpretation in reading the results. I subscribe to the method you used.
However, I also subscribe to using the most accurate loads as listed by Sierra and Nosler and watching the velocities generated by other powders that coincide with the powder you chose and the velocity of their accurate loads.
There is little difference in the results from the two 4831 powders.
 
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My ladder testing expereince would lead me to play with the 7-9 node. You WILL find another node in there and I would be willing to bet that it is going to be in the high 8-9 range. My most accurate loads are normally at the max published zone and often over. My next step would be to break that node down into .2gn increments starting at 8.0 and shoot another ladder so 8.0, 8.2, 8.4, 8.6 - - 9.8, 10. 15 more rounds to determine maximum accuracy. THEN I'd start playing with components and bullet seating.
 
Thanks for the good input so far guy's. There seems to be some valid points here so I have decided I will: (see below)

Ladder test at short distances really don't tell anything. IMO having done a few myself at theses distances. I just shoot 5 shot groups 2 or 3 hundred meters and look at the vertical dispersion instead.
However if I were to choose a range to do additional work a load base on your ladder test I would choose 5 and 6 on your 300m target because between those two loads they are dead flat.

Try this, I'll explore these loads a little further.

Ignore the guy above.
The ladder test is a great method to develop a load with minimal shots.
200m is a good distance for it. Any distance you don't get a ragged hole at is a good one.
So, based on this method, load #8 is the load you have found.
You can confirm it by shooting a 5 hole group at 200 or 300 and be done with it.

I'll also try this one and shoot a couple of groups to see how they look.

My ladder testing expereince would lead me to play with the 7-9 node. You WILL find another node in there and I would be willing to bet that it is going to be in the high 8-9 range. My most accurate loads are normally at the max published zone and often over. My next step would be to break that node down into .2gn increments starting at 8.0 and shoot another ladder so 8.0, 8.2, 8.4, 8.6 - - 9.8, 10. 15 more rounds to determine maximum accuracy. THEN I'd start playing with components and bullet seating.

Finally I will do this and shoot another ladder test. I tend to believe that I will find what I am looking for somewhere here.

If anyone else can see something I should try, let me hear it. I'm open to suggestions and am willing to experiment.
 
I was hoping you'd say that so by any means, go ahead and experiment.
After all, any of the shots could have been a "pulled" shot and the nice node might not even be a node.
Take and keep detailed notes and draw your own conclusions.
And once you're done, switch to a different powder and start over :cool:
 
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