Rifle load development methods compared

[Laphroaig]

I've done a couple of Audette type ladder tests. For me its a starting point when, for whatever reason, I'm determined to use a certain powder/bullet combination from the get go. A couple of times I was able to pick out "nodes" that pointed me in the right direction ASAP. Other times I either couldn't interpret the results, or there weren't nodes in the classic sense. If nothing else, you get a nice evolution of primer flattening from starting loads up through book max. If you chronograph you get an idea what you're going to get as you zero in on a load.

I don't think that the Audette method was ever intended to be the be all end all of load development, just another source of data that might save some time in the process. (I think that was Creighton Audette's almost exact words about the method in the NRA high power seminar notes on handloading published in the 1980's) Others have modified it, like the OCW and apparently Saterlee (I have to Google that one) and attempted to improve it. The one shot per charge in the Audette method does put a lot of onus on the shooter and all chrono readings/bullet groups have a degree of scatter that could skew the results a little bit too.

 

[JFrank]

Varminterror, the "groups" means the 20 bullets. If you want to call it "string", go ahead. Its ok if you want to preach your religion. Keep doing it. Since none of us can verify your claims in person, you will always be right.

The guys at my club are bad reloaders? Is that all you got? I am NOT giving them advice, I am asking for ANYONE on earth to prove this ladder method works, or other methods. They simply can't do it repeatably.

20 shot strings are common. Thats .1 grains each. Thats 2 grain spread. You are not more or less an expert by saying you do 10.

If I was with you, you would completely fail, make excuses, and I would laugh.

I sir believe in Nature Boy and his load development techniques 100% .
They work for him , he shows his work and posts his findings .
You sir ,on the other hand have derailed his thread with negative comments towards another member and development techniques you say will not provide repeatable results.
I would love to hear about your magic method of load development and see your match winning results on the target.
.( But only on a separate thread.)
J
Apologies to the OP

 

[Demi-human]

I feel bad for your local guys,

There's nothing quite like sitting down and trying to collect your thoughts for a good string, group, whatever, while some Doubting Thomas that noticed your chronograph snickers over your shoulder.
I have no doubt that these are seasoned shooters already set in their ways by decades of curmodgeoning. Definitely not one of the multitudes of new and learning shooters just beginning to dabble in the rifle world lately...

As proof of load testing actually working I posit the entire International Bench Rest Shooters League.

Though I am sure they have no proof as well. After all, one can't wake a human that only pretends to sleep...

 

[Nature Boy]

I sir believe in Nature Boy and his load development techniques 100% .
They work for him , he shows his work and posts his findings .

I have to say this again. The method I’m using for developing loads at 100 yards for longer range shooting is not mine. A fella by the name of Erick Cortina came up with it (4 time Texas Long Range F Class champ)

It’s a derivative of the OCW method, which shows that there is more that one way to skin the cat.

But it works.

 

[Legionnaire]

Can't argue with success.

 

[NATO Reloading]

This method here, is probably the most logical method out there since it focuses on POI.

Richard U. is a good guy

 

[JFrank]

This method here, is probably the most logical method out there since it focuses on POI.

Richard U. is a good guy

I’m sure Richard U is a good guy.
I understand the OCW method of load development , it’s quite popular with PRS shooters but that’s not the only method.
My question was regarding your magic method and posting your results and please don’t tell me you shoot steel.

 

[Nature Boy]

My question was regarding your magic method and posting your results.

Yes! We all want to learn

 

[MCMXI]

So @NATO Reloading believes that the loads that show relatively small changes in velocity despite a change in charge weight are in fact due to other errors in the system and are not indicative of a velocity node. He believes that if the same test was conducted numerous times, the charge weight range over which the velocity nodes occur would change in a random manner. This seems easy to prove or disprove.

I'm sure we all know that for a load to be accurate the bullet has to leave the muzzle when the barrel is in the same position relative to the target. That's the first requirement regardless of the range at which we're trying to hit something. At close range, BC, bullet weight and velocity are not as critical. Since there are multiple accuracy nodes over a charge weight interval, it stands to reason that one round from each of five accuracy nodes, all with different charge weights and velocities, could shoot well at 100 yards because the bullet is leaving the muzzle when the barrel is in the same position relative to the target. Those same five rounds would most likely not produce a good group at 500 yards due to the differences in velocity for each bullet. So as the range is extended, we're looking for an accuracy node that coincides with a velocity node and we're either assuming or inferring through measurements that the bullets are similar enough to have the same flight path to the target. So are the accuracy and velocity nodes dependent or independent? The OCW method assumes that they're independent since velocity is not a significant variable, or at least not directly.

I was talking with a technician at Berger recently and asked him why he thought bullet seating depth affected precision. I'm curious as to what folks here think is going on when bullet seating depth is adjusted. My simplistic thought is that it's "merely" tuning bullet barrel time i.e. finding the moment where barrel movement is minimal. Berger has some info on their website where they talk about accuracy nodes over a .120" COAL range. They describe varying bullet jump in .040" increments for four loads to zero in on an accuracy node.

So what is the explanation for velocity nodes over a wide range of charge weights?

 

[Nature Boy]

....,the precision bar is considerably higher for F-Class than it is for Service Rifle, and obviously it's even higher for Benchrest, but the gap between F-Class and Benchrest seems to be getting tighter (just a guess).

The reason for the difference is that there’s no target pulling for bench rest. If the wind conditions are favorable let all your rounds fly. In F Class you have to wait for the target to go down, a spotter placed in your bullet hole, and come back up for scoring. You can’t machine gun all your shots for record when the wind lays down

If course I’m stating the obvious to you.

Here’s why we should listen to the bench rest community on load development. It doesn’t matter if you’re shooting F Class or PRS, those guys have figured out a lot when it comes to tuning loads for rifles and if accuracy is your objective then the techniques they have come up with matter.

If we don’t think there’s something to this then it’s
all voodoo dodo. 3 shots in a paper plate is good enough

 

[MCMXI]

@Nature Boy , your method and repeatable results certainly indicate that it's not "all voodoo dodo". I like a methodical approach to working up a load, but I also want to understand the why. It's easy to understand that a good group requires that the bullet leave the muzzle when the barrel is in the same position relative to the target each time. It's also easy to understand that at longer ranges the velocity needs to be as consistent as possible. How those two variables are influenced, tweaked and ultimately controlled is not as simple. The fact that we have contentious discussions about such things is indicative of the complexity of the problem.

 

[Nature Boy]

@MCMXI

When it comes to this subject, we are a sub set of a sub set related to chasing the accuracy demon in rifles.

I see guys post similar load data for tuning pistol accuracy. All I care about is will it cycle and not blow me up. God I hope I don’t get the accuracy bug with pistols

There’s no end to this, enter at your own risk

 

[JFrank]

^^^
I’ve been told that the best way out of a hole is to stop digging

 

[Walkalong]

Want to chase the accuracy bug?

Get a Benchrest rifle and go to a registered match.

Two targets shot with the same gun the same day, same load, same nut behind the trigger. Targets 2 & 3 of an aggregate.

I saved them to remind me how one shot can ruin an agg.

The .186 will work, the four in and one out .398 will not. *Sigh*


Or you could shoot at flies at 100 yards.

 

[Walkalong]

Long range guys need small ES loads. It doesn't matter at 100 & 200 yards shooting tiny groups where you need to average in the teens or small twos, but it does matter at long range.

A 1/2" @ 100 yards load with a tight ES is better at 1200 yards than a .200 @ 100 yards load with a big ES. If you have a large vertical dispersion at long range you will struggle.

Different kinds of accuracy needs for different applications.

I'll likely kick your butt at 100 yards with my 6 PPC shooting for group size, but you will kick my butt every time at 1200 yards if I shoot my 6 PPC.

 

[MCMXI]

I played with QuickLOAD a bit this afternoon and for a 6.5x47 Lapua 130gr load with 41.6gr of H4350, the barrel time decreased by 0.014 ms moving the bullet from the lands to .040" off the lands, i.e. a 1.2% reduction in barrel time. As the bullet moves further into the case, the pressure increases which means higher velocity and shorter barrel time. What's interesting to me is that moving the bullet .040" has a bigger effect than keeping the bullet where it is and increasing the charge weight by 0.2gr which decreased barrel time by only .008 ms. It looks like .005" change in seating depth results in a .002 ms change in barrel time. QL is theoretical of course but it's often incredibly close when it comes to predicting velocity so these trends are probably reasonable.

 

[Varminterror]

This method here, is probably the most logical method out there since it focuses on POI.

Richard U. is a good guy

More evidence you do not understand the Audette Ladder method which you say doesn’t work. The Ladder method, just like the Newberry OCW method, focuses in vertical POI shifts.

Fundamentally, the OCW method in the video and the Ladder method are the same - different twists on the same principle. Vary charge weights, and observe the influence of the changes upon POI. OCW uses multiple points of aim, while Ladders shoot the same POA.

So you are saying one method which focuses upon powder charge influence on POI is flawed and cannot work, while promoting ANOTHER method which focuses upon powder charge influence on POI is the most logical method out there... Talking out of both sides of your mouth, here.

 

[JFrank]

Long range guys need small ES loads. It doesn't matter at 100 & 200 yards shooting tiny groups where you need to average in the teens or small twos, but it does matter at long range.

A 1/2" @ 100 yards load with a tight ES is better at 1200 yards than a .200 @ 100 yards load with a big ES. If you have a large vertical dispersion at long range you will struggle.

Different kinds of accuracy needs for different applications.

I'll likely kick your butt at 100 yards with my 6 PPC shooting for group size, but you will kick my butt every time at 1200 yards if I shoot my 6 PPC.

View attachment 843222

Sweet rifle, what weight class do you compete in?
I hate PPCs ( they always kick my Butt)
Just messin
J

 

[Varminterror]

Here’s an example comparing OCW method to Ladder method. These pics are from a thread where a user on another forum three years ago attempted an OCW test, but wasn’t sure how to process the results - and asked if he should go back to Ladder methods, without realizing, fundamentally, they are really one and the same, just in a different shape.

His original target:


Developed for analysis by OCW standards:


In this case, the “wave” settles down considerably in the range of loads #5, 6, and 7, so loading in this range will produce the least vertical dispersion at longer distances of any charge weights explored.

For comparison, I transcribed his “OCW test” into a “Ladder test” by overlaying dots on the bullet holes, then superimposing all of the individual POA’s into one as if they had been fired at the same POA, and then assigning the vertical center of each for analysis - THIS is a Ladder test target:


When observed as a Ladder test, the same result appears. The vertical change between neighboring charge weights is the least between groups of charges #5, 6, and 7, so regardless of which of these two tests this shooter would choose, the targets would yield the same result - that loading within 5-7 will minimize sensitivity of POI to charge weight for long range shooting.

What I have found remarkable in the last few years, after using OCW & Ladder methods for many years prior (or some permutation among and between), is how incredibly well the Satterlee Velocity curve method will predict these same results, with far less shooter influence (read: error) upon the results. The shooter can’t influence muzzle velocity in the same way they can influence POI, so this method is less sensitive to shooter error. I have blended a 100yrd OCW method with the Satterlee method for my last two 6mm creed barrels to great success (Satterlee velocity curves don’t really need a target at all, but if I’m shooting, I might as well shoot at SOMETHING, right? It also gives me a chance to check in on my seating depth). My previous OCW method tests were shot at 300yrds, and my Ladders typically at 500-600 to promote sufficient vertical dispersion to satisfy the analysis, but I’ve been able to run this 100yrd combined method even at a windless indoor range, significantly reducing the time commitment to travel to and set up targets for my 300 or 600yrd ranges, and significantly reducing environmental influences to errors in the testing. The results have yielded first round hits, time and time again, out to 1400yrds in competition with the loads developed in this method - as well as delivering rather satisfyingly small groups on paper as well.

 

[Walkalong]

what weight class do you compete in?

I shot that 10 1/2 Lb rifle in all classes, including unlimited.

 

[JFrank]

Beautiful
Those things are crazy accurate, my friend shot those for years.
Told me if he agged a quarter inch group for the weekend that would be good enough for 85th place or worse...

 

[JFrank]

I’m looking forward to that young fella starting a magic load development thread.
Always good to learn something new I figure !
J

 

[Varminterror]

For discussion on a lazy Sunday afternoon:



I shot this OCW type target a few weeks ago - the target was meant to be inconsequential during a velocity profile check, and there wasn’t much effort put into setting up or shooting this target. I was also working on a new trigger control technique. Just doesn’t seem right to shoot for velocity only, without shooting AT something. I fired from a bipod on thin carpet at the front, and a weibad fortune cookie laid on its side at the rear. 1-2min between shots, 5min (timer) between strings. Indoors, no wind, controlled temp. Shot as 3 strings of 8 shots, “round robin” as guys call it. Squares and circles are 1”. Largest group (41.0) is .47moa, smallest (42.0) is .11moa.

Top row is 41.0, 41.2, 41.4, 41.6, & 41.8, second row continues 42.0, 42.2, & 42.4grn.

So what charge weight deserves further investigation from this preliminary test? Which stands out as “best,” and why?

*note - horizontal offset was caused by the Magnetospeed V3 hanging on the suppressor, and as such, ignored, POA held center of each sticker.

 

[JFrank]

What caliber are you shootin

 

[Nature Boy]

As I read it it’s 41.0 to 41.6