Picking An Accuracy Node - Need Help Understanding

Trapper79

Trapper79

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Doing some testing for my Remmy '06 and had a question. I've watched countless videos and read pretty much all of 6mmbr.

I'm testing H4350 and 180 grain Speer BTSP. I started at book minimum and worked up to max in .3 grain increments. 3 shot groups of each.

Clearly I can see my groups start small, open up and then close in two separate occasions. Accuracy nodes - perfect.

This is where I need help. Some say just pick the best group and load for that. Others say the best choice is picking between the nodes and not the tightest group. If I pick between the nodes, my groups are not the best but from what I understand - these are my nodes my rifle likes? So confused! Need help!

Thanks!

~Trap
 
Can't see why one would shoot a load that you can prove is not accurate. Suggestion: load up 20 at each node and shoot them in 5 shot groups. Analyze your results and chose the one that is the most repeatable/ most consistently precise.
 
For at least the last 75 years, the one standby load for the 30-06 and 180 grain bullets, has been IMR4350, in loads from 56 grains and up to maybe 58 grains in some rifles. This is an international load, considered the go to load for any 30-06 rifle.
Why wouldn't you just use this super time tested load, and if you want better accuracy, work on your rifle?
 
Would you theoretically choose the highest velocity with the best node (ahead of detrimental signs)? I'm also new to this so I'm just wondering.
 
Various load manuals will high light or list the highest velocity loads first, note velocity not accuracy because they may or may not be accurate depending on the firearm. If I have a choice velocity or accuracy I take accuracy. As stated for certain calibers there's tried and true rounds so why re-invent the wheel. It doesn't hurt to have a back-up load with a different powder just in case powders not around, but stick to what works.
 
Well, I'll admit, i have information overload trying to decipher all of 6mmbr website + a plethora of others suggesting different ways of finding a good load. Just trying to figure it all out with the hopes of an experienced reloader that can 'dumb' it down for me to grasp :)
 
I will look around for some IMR4350. Not sure how I came upon choosing H4350. I had no idea this was THE powder to use. Good to know. Thanks!
 
grumpyold said:
Various load manuals will high light or list the highest velocity loads first, note velocity not accuracy because they may or may not be accurate depending on the firearm. If I have a choice velocity or accuracy I take accuracy. As stated for certain calibers there's tried and true rounds so why re-invent the wheel. It doesn't hurt to have a back-up load with a different powder just in case powders not around, but stick to what works.
Click to expand...

Good to know. I did not quite understand how the manuals and their loads were listed in order. If I understand you correctly; best to start from the top?
 
Trapper79 said:
Doing some testing for my Remmy '06 and had a question. I've watched countless videos and read pretty much all of 6mmbr.

I'm testing H4350 and 180 grain Speer BTSP. I started at book minimum and worked up to max in .3 grain increments. 3 shot groups of each.

Clearly I can see my groups start small, open up and then close in two separate occasions. Accuracy nodes - perfect.

This is where I need help. Some say just pick the best group and load for that. Others say the best choice is picking between the nodes and not the tightest group. If I pick between the nodes, my groups are not the best but from what I understand - these are my nodes my rifle likes? So confused! Need help!

Thanks!

~Trap
Click to expand...

What you describe is a 'ladder test' this procedure helps finding a 'sweet spot' for the components used.

In any testing an accurate and repeatable chronograph is key to getting and measuring good results.

Just a suggestion : do some research on the Optimum Charge Weight (OCW), some of the attributes to OCW is a powder that fills the case near 100% or over 100% but not 100%. Low Extreme Spread (ES) compared to other powder combinations, test in varying weather conditions you will find that the load is tolerant to changes and in minor loading variances, this means that COL can vary a bit as does charge weight, by a few 1/10ths of a grain, plus other component variances.

Once you are satisfied that the load is tolerant to the above variances and ES is low, always strive for the lowest possible, single digit is preferred. It is time to tune the load to a node, this is actually Optimum Barrel Time (OBT). This can be done with seating bullet for a COL that produces good accuracy or by charge weight, I do it by charge weight. Chris Long has produced a chart that describe barrel time in mS, this combined with the Quickload program will get you on the exact barrel time for the load and barrel length.

The above only hits the highlights of the procedure and concepts. In practice to find the best load for your rifle takes one trip to the range to ascertain powder burn rate and resultant velocity, adjust program (QL) to this tune charge weight to (OBT) and your done.

But as H4831 says the classic load for your components are IMR and H4350 at 56grs and up. You are close to optimum right there and it should take little to get it to shoot very well providing a mechanically sound platform.

I've briefly described a method that many years of experience has proven.
 
BCBRAD said:
What you describe is a 'ladder test' this procedure helps finding a 'sweet spot' for the components used.

In any testing an accurate and repeatable chronograph is key to getting and measuring good results.

Just a suggestion : do some research on the Optimum Charge Weight (OCW), some of the attributes to OCW is a powder that fills the case near 100% or over 100% but not 100%. Low Extreme Spread (ES) compared to other powder combinations, test in varying weather conditions you will find that the load is tolerant to changes and in minor loading variances, this means that COL can vary a bit as does charge weight, by a few 1/10ths of a grain, plus other component variances.

Once you are satisfied that the load is tolerant to the above variances and ES is low, always strive for the lowest possible, single digit is preferred. It is time to tune the load to a node, this is actually Optimum Barrel Time (OBT). This can be done with seating bullet for a COL that produces good accuracy or by charge weight, I do it by charge weight. Chris Long has produced a chart that describe barrel time in mS, this combined with the Quickload program will get you on the exact barrel time for the load and barrel length.

The above only hits the highlights of the procedure and concepts. In practice to find the best load for your rifle takes one trip to the range to ascertain powder burn rate and resultant velocity, adjust program (QL) to this tune charge weight to (OBT) and your done.

But as H4831 says the classic load for your components are IMR and H4350 at 56grs and up. You are close to optimum right there and it should take little to get it to shoot very well providing a mechanically sound platform.

I've briefly described a method that many years of experience has proven.
Click to expand...

Thank you very much fine sir for the explanation. Sorry for all the questions. I'll be amidst doing something along the way(reloading, deciphering...) and I have so many questions. Thank you to all who have responded.
 
Trapper79 said:
Doing some testing for my Remmy '06 and had a question. I've watched countless videos and read pretty much all of 6mmbr.

I'm testing H4350 and 180 grain Speer BTSP. I started at book minimum and worked up to max in .3 grain increments. 3 shot groups of each.

Clearly I can see my groups start small, open up and then close in two separate occasions. Accuracy nodes - perfect.

This is where I need help. Some say just pick the best group and load for that. Others say the best choice is picking between the nodes and not the tightest group. If I pick between the nodes, my groups are not the best but from what I understand - these are my nodes my rifle likes? So confused! Need help!

Thanks!

~Trap
Click to expand...

I am really far from an expert, but I did a ladder test at 200, got me on the path to a 5/8" group at 100. I just read up on here and the internet and did my best. This was for a hunting rifle, so my node was right near the limit of my rifle that I chose. ( 270 win, 59gr RL22, 130 grain bullet )
 
RatFink said:
Would you theoretically choose the highest velocity with the best node (ahead of detrimental signs)? I'm also new to this so I'm just wondering.
Click to expand...

If this question was directed at me, I consider "accuracy nodes" in shooting, on a par with bigfoot stories.
 
OP: Did you chrono the load? To find best ES/SD?

My preference is best single digit ES/SD, pref. near max load, then .1gr several over and under. Take best 5 shot group.
 
I usually test at the distance I plan to shoot or at least attempt to get the best test at say 300m hopefully for a good accurate load to proof/try at further distances.

Having said that, considerations must include what bullets are used as some will look good at 300m but maybe not so perfect at 100m. I ran into that with some Amax once. Generally though, if it is good at 300m it is good or better at 100m. You didn't mention test distance.

I have tried OCW for yote loads where I can see the groups move and tighten/loosen. I have also tried the ladder test and picked the highest velocity/accuracy node, mainly looking for no vertical grouping.

Regardless, in either case taking the best load(in OCW, taking it for hunting and then further refining the ladder test loads and then retesting that refined load to a final load for accurate distance shooting ). I look at OCW more as a quick way to a good load for that barrel vs ladder testing for a more accurate load for one case at a time for longer distance precision.

My 2 cents.
 
Trapper79 said:
Doing some testing for my Remmy '06 and had a question. I've watched countless videos and read pretty much all of 6mmbr.

I'm testing H4350 and 180 grain Speer BTSP. I started at book minimum and worked up to max in .3 grain increments. 3 shot groups of each.

Clearly I can see my groups start small, open up and then close in two separate occasions. Accuracy nodes - perfect.

This is where I need help. Some say just pick the best group and load for that. Others say the best choice is picking between the nodes and not the tightest group. If I pick between the nodes, my groups are not the best but from what I understand - these are my nodes my rifle likes? So confused! Need help!

Thanks!

~Trap
Click to expand...

You can certainly fine tune with some of the more extreme ladder testing and chrony work using seating depth and 0.1 grain chasing. As it is though, you have two known pretty good points to work with and I would suggest spending time at the range deciding which one is going to work the best for you, your rifle and the bullet. The lower load will have less initial velocity and may or may not like to be shot at distance with decreased stability. The slower a bullet starts, the quicker it loses speed and energy which means increased time to target, therefore more bullet drop and time for wind to move it around. On the other hand, it also means that your rifle barrel and brass is probably going to last longer. Pick whichever load works best for your conditions. Some people actually shoot two loads, at silhouette shooting for example. A lesser load for the closer ones, saving their shoulder and rifle, and the next node up for the long range targets so that the energy is there where it is required. Of course this means quite a bit of range time prior to shooting the silhouettes so that you already 'know' where the bullet should end up so that you can adjust your scope or reticle reference properly, as the point of impact will change. It could and likely will change quite dramatically between charges.
 
Nodes can be usefull also for different purposes. Suppose you have two loads with exactly the same accuracy at a given distance, but one (lighter load) produces 2800fps and the other (heavy load) 3000fps. There's an interest in both. Suppose accuracy is exactly 100% the same.

You could use the lighter load for target shooting, so as to save on powder and obtain less recoil on those days you're gonna shoot a couple hundred rounds, but if hunting with your rifle, you'll pack the heavy load to make sure that moose falls down and stays down when your shoot it. Actually you might choose the heavier load for hunting even if its accuracy is lower, cause your target is larger.
 
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