Ladder Test, real or Imagined

[Lumpybrass]

While working up a load for a new rifle, I have seen a lot of talk about the 10 shot ladder test to identify an optimum powder charge.
I apologize for such a long winded post, but it needs to be if done correctly.
The ladder test is aid to find a "node" in the velocities recorded which then identifies a sweet spot.
Nodes were made known to me in benchrest shooting. They were described as the extreme vertical muzzle travel at the top and bottom movement. Between top and bottom the barrel was moving fast, compared to the movement stopping to change direction at the top or bottom. POI would suffer the least when the bullet left the barrel at these top or bottom nodes. Some competitors used compensators that added weight to the muzzle that was adjustable towards the chamber or barrel end. This helped a given bullet velocity exit on a node.
Now here comes the problems for me understanding the ladder test. A graph is plotted with the velocity of powder charges forming a somewhat linear slope. Users are looking for an increase in powder charge but little or no change in velocity. On the slope it looks like a plateau . The theory is that powder charges can vary slightly in that area with little effect on POI.
To me this is like saying a shot went high or low due to gravity changing. No different than burning more powder and NOT seeing an increase in pressure and velocity. What could possibly effect the velocity like that. Physics is not flexible.
So, you might say there are a lot of knowegeable gun folks who endorse the ladder system whole heartedly. I agree, there are. I watched many you-tube deminstrations where this methd was explained, demonstrated, and then graphed the results with conclusions.
The graphs and conclusions were where I had trouble. Most were really stretching to pick out a plateau . Most were very slight and in one case the demonstrator fired two rounds at each charge enabling two curves to be plotted. One was dead straight with the other having a flat spot. He ignored the straight plot. His work was not repeatable.
Most all seemed to have some level of fustration with the results and the challenge of picking the magic spot.
I believe these "nodes" are the result of variables adding errors to the data. Charge weight accuracy, bullet variables, time in hot chamber before firing, chamber temps, seating depth consistency.
An example of chance variables adding in a good direction was a you-tube guy all excited by one group that was very nice. He discounted that it had a 50 fps ES. Groups below and above were poor, but that one had his attention because chance came together. The blind squirrel deal.
The alternative to the 10 shot ladder test is like I do; burn a ton of ammo to get my groups. But, I always hope to have a repeatable load at the end.
I now expect to get hammered. Thanks for reading this far.

 

[Autofire]

I now expect to get hammered. Thanks for reading this far.[/QUOTE]

I love this article about OCW (Optimum Charge Weight) vs. The Ladder Test. http://optimalchargeweight.embarqspace.com/ocw-vs-ladder/4529811360
there is also a good discussion on this in the reloading forum. Not sure how to link to it.

 

[Supersubes]

A post was made about this very subject you’re talking about, just the other day. It was well layed out, and had some graphs. His conclusion was like yours.

To me a simple ladder is incomplete. Good for finding a maximum charge at best, because there just arent enough data points.

A true OCW is the better method, which is just several ladders run together, fired in round robin sequence. Perfect, no, but dang sure better than a ladder.

 

[Deleted member 113831]

I now expect to get hammered. Thanks for reading this far.

You are not wrong. The issue is that everybody is looking for a short cut. Some get truly lucky and think they nailed it....others miss the mark entirely and lack the skill or experience to even tell the difference. I would say that probably 90+% of people doing this test have absolutely no idea of the parameters and conditions that must be present in order for it to have a chance of working.

I have even seen people attempting this with gas guns. Then they come on here and ask what they are doing wrong!

 

[SupressYourself]

I'm not saying you're wrong, and the OCW test seems to have merit as well, but the velocity "ladder" test has worked for me.

Due to all the noted variables that cause normal fluctuations in ES, it helps to fire more shots at each charge. I shoot 3 and plot them along with the average. Sometimes you have to throw out one outlier to see the "node". It's almost never going to be completely flat, but the increase will not be as steep.

This was some initial testing on a new barrel. I chose the lower node around 3130 FPS. Since then the barrel has sped up quite a bit. It now only takes 42.5 gr of H4350 to get there, but I've run more ladder tests and there's still a flat-ish spot around 3130 that also happens to group well. Coincidence? possibly....

 

[Supersubes]

I'm not saying you're wrong, and the OCW test seems to have merit as well, but the velocity "ladder" test has worked for me.

Due to all the noted variables that cause normal fluctuations in ES, it helps to fire more shots at each charge. I shoot 3 and plot them along with the average. Sometimes you have to throw out one outlier to see the "node". It's almost never going to be completely flat, but the increase will not be as steep.
View attachment 7031570

This was some initial testing on a new barrel. I chose the lower node around 3130 FPS. Since then the barrel has sped up quite a bit. It now only takes 42.5 gr of H4350 to get there, but I've run more ladder tests and there's still a flat-ish spot around 3130 that also happens to group well. Coincidence? possibly....

You tripled the number of rounds one would fire in a typical ladder though, which makes the OP’s point, no? Both of you are saying the same thing. More rounds to sort out the variables.

 

[Deleted member 113831]

Nobody has ever explained to me the physics that makes a powder charge burn consistently at a lower pressure... then burn less consistent as the charge increases... until it reaches a magic point where it burns consistent again... and then starts to get erratic once more.

 

[SupressYourself]

You tripled the number of rounds one would fire in a typical ladder though, which makes the OP’s point, no? Both of you are saying the same thing. More rounds to sort out the variables.

Agreed. More data is always better, but you have to find your "happy medium" so you don't burn out your barrel trying to find a load.

 

[Autofire]

Nobody has ever explained to me the physics that makes a powder charge burn consistently at a lower pressure... then burn less consistent as the charge increases... until it reaches a magic point where it burns consistent again... and then starts to get erratic once more.

I am with you on this one!

 

[Supersubes]

Agreed. More data is always better, but you have to find your "happy medium" so you don't burn out your barrel trying to find a load.

Agreed on making it somewhat efficient so you don’t smoke barrels. I too shoot the 87 in the 6 creed, and my gun shoots similarly well in the range you chose. Should equal some friendly barrel life as well.

 

[918v]

What could make the velocity stay put with an increase in powder charge?

An increase in bore diameter.

It has been theorized that in addition to barrel whip, there is an increase and constriction in bore diameter during the firing cycle.

 

[Deleted member 113831]

What could make the velocity stay put with an increase in powder charge?

An increase in bore diameter.

It has been theorized that in addition to barrel whip, there is an increase and constriction in bore diameter during the firing cycle.

Scott himself has said that he is using heavy for caliber bullets (147 grain in the video) and slow for caliber powders (H4831 burn rate). He is also at or above book max charge, and running .010" off the lands.

What is happening in his specific situation is that the total weight of the ejecta, combined with 100%+ load density and maximum pressures has culminated in the ultimate point of diminishing returns for that combo. In the context in which it was actually used by Scott , it makes perfect sense.

Problem is, almost no one uses it the way Scott himself does. Therefore, we get endless threads on why it does / doesn't work.

 

[sabrecross]

Scott himself has said that he is using heavy for caliber bullets (147 grain in the video) and slow for caliber powders (H4831 burn rate). He is also at or above book max charge, and running .010" off the lands.

What is happening in his specific situation is that the total weight of the ejecta, combined with 100%+ load density and maximum pressures has culminated in the ultimate point of diminishing returns for that combo. In the context in which it was actually used by Scott , it makes perfect sense.

Problem is, almost no one uses it the way Scott himself does. Therefore, we get endless threads on why it does / doesn't work.

I found similar results to what you are describing. I trend in a similar manner when working up a load. Since I am shooting a magnum, I use a slower burning powder with a near maximum charge, close to the lands. I also do a multiple shot ladder test (three shot groups) to try and find a trend. It is easier for me this way and it is only an extra 20 spent rounds.

 

[steve123]

Just commenting

The way I do a ladder test might be different than some.

It has to be a calm-ish morning, lacking mirage.
A total PITA but I drive down to mark each shot - which lets the barrel cool the same amount of time. The barrel never even gets warm.
Is optimum at a farther distance, best I've found is 400Y.
Has to be an accurate rifle or it'll be hard to see where the node is.
You have to be a good shot, no error in form, no screwing up a shot, or use benchrest aids.
.1 grain increments in a medium sized case provides more info.

Yes, for whatever reason I've had results that weren't perfectly telling, it's been rare (usually the wind came up, or I didn't load the last few charges high enough to reach the high node) and the opposite has worked most of the time with proven results at distance later on. The worst that can happen is to do it over, then you have two sets to work off of.

One can take load development as far as they want. If you want to put in the time and the work then go for it. Things are ever changing, ever wonder why the BR shooters bring their reloading equipment to their matches?? It's because tune's change throughout the day. If I can put 1/2 moa or less vertical down range that's good enough for me but less makes me smile more.

Do vld's go to sleep? Why do short range BR shooters use flat base bullets exclusively? Does doing load work at 100Y with long bullets tell you what the bullet is doing at the distances you'll actually be using them? Can a load with more SD give smaller vertical than one with higher SD? If asked I'm not even answering back, it's up to you to ask yourself and investigate.

^^^^ My answer is I don't much care, lol, a ladder test worked good enough to win matches before. I'm getting old and I won't be winning any more centerfire matches but it sure worked back then.

 

[Deleted member 10043]

Witchcraft. Even the word node is used inappropriately.

 

[Deleted member 10043]

To add a stick in the spokes you can pick any safe MV you like and just work with seating depth to get an accurate load. From there until the death of the barrel is just chasing the lands. The level of statistical hit probability on any target is immaterial between a .5 MOA rifle and a .3 MOA. It is down to shooter skill and I see way too much bullshit on load development as a means to a dead end easier softer way. In essence, finding the most finicky area is self defeating in the long run.

 

[Steel head]

I’ve always done a 3-5 shot group ladder rest.

My new barrel on my 260 just broke 100 shots so I’m going to try the 10 shot ladder with some established brass and scale verified charges.
I’m interested to see how it pans out.

 

[918v]

Scott himself has said that he is using heavy for caliber bullets (147 grain in the video) and slow for caliber powders (H4831 burn rate). He is also at or above book max charge, and running .010" off the lands.

What is happening in his specific situation is that the total weight of the ejecta, combined with 100%+ load density and maximum pressures has culminated in the ultimate point of diminishing returns for that combo. In the context in which it was actually used by Scott , it makes perfect sense.

Problem is, almost no one uses it the way Scott himself does. Therefore, we get endless threads on why it does / doesn't work.

If the bore diameter theory is correct, then it CAN explain what you just described. The velocity plateaus coincide with the bullet riding a bore “bubble” all the way to the muzzle. You would need to add a substantial amount of powder to get the bullet to outaccellrate the bubble and enter a constricted area of the bore where the bullet is again properly sealed and can efficiently take advantage of additional powder at a finer increment level.

The problem with reaching the end of your available case volume is you cannot add anymore powder. If you could and the cases held the additional pressure and your rifle didn’t explode I’d betcha you would reach another node.

I know... sounds like BS.

 

[Deleted member 113831]

If the bore diameter theory is correct, then it CAN explain what you just described. The velocity plateaus coincide with the bullet riding a bore “bubble” all the way to the muzzle. You would need to add a substantial amount of powder to get the bullet to outaccellrate the bubble and enter a constricted area of the bore where the bullet is again properly sealed and can efficiently take advantage of additional powder at a finer increment level.

The problem with reaching the end of your available case volume is you cannot add anymore powder. If you could and the cases held the additional pressure and your rifle didn’t explode I’d betcha you would reach another node.

I know... sounds like BS.

Peak pressure (and therefore biggest bore expansion) happens about 2 inches in front of the chamber, so I'm not buying it. I would subscribe to the bore oscillation theory as described along with "Optimal Barrel Time" explanation before I would to that one.

 

[Deleted member 10043]

If the bore diameter theory is correct, then it CAN explain what you just described. The velocity plateaus coincide with the bullet riding a bore “bubble” all the way to the muzzle. You would need to add a substantial amount of powder to get the bullet to outaccellrate the bubble and enter a constricted area of the bore where the bullet is again properly sealed and can efficiently take advantage of additional powder at a finer increment level.

The problem with reaching the end of your available case volume is you cannot add anymore powder. If you could and the cases held the additional pressure and your rifle didn’t explode I’d betcha you would reach another node.

I know... sounds like BS.

A lot of dying previous generation simply called it finding the max MV then backing off .5 grains and fine tune with seating depth and a tenth of a grain here or there. I see them a lot and they have no problem with accuracy. However, I do see case failure eventually. And act a little baffled every time the barrel is gone. They have forgotten more about loading then I will ever know but do they have to go absolutely to the max all the fucking time!?!?! They don't mind an alibi. They can read the wind while the rest of are going hurry the fuck up then, lol.

 

[JSchell1309]

I did a simple ladder test with 3 shots at each grain increment and increasing them 0.3 grn per step. I started in the middle of recommended load for 6.5 creed and went up to book max. Left Y axis is average velocity and right Y axis is Std dev and ES.

This was enough for me to be happy with the “nodes” of low ES at 40.3-40.6 and 41.8. I still need to follow up on this, next was to play with OAL and distance from lands at 40.5 grn increment and see how it groups. For my shooting I’ll be happy with that load f it’s around 0.6 MOA or less. All groups on above graph were between 1MOA to 0.28 if I recall correctly. I want to say the “nodes” above weren’t necessarily the best group, but they will be the most predictable for DOPE.

More data points are always better, but there is a point where you just need to get out and shoot the damn thing vs. wasting ammo and barrel life chasing some “optimum” load for your barrel. I plan on stopping when I achieve something repeatable and predictable to start practicing with.

I will also add I am an amateur and just working on handloading and precision shooting. Take all this with a grain of salt, just more data out there in the cloud.

In the graph I am trying to visualize the orange and grey points of ES and Std. Dev. You can see how they flow down, up, and down, through the charge weights.

 

[patriot07]

I tried the ladder test one time and it was an epic fail. Max velocity stability fell exactly out of line with max group accuracy.

Ended up finding it was a complete waste of time and shot a bunch of groups to find my node, and it shot great from then on. Needless to say, not a fan...

 

[steve123]

Witchcraft. Even the word node is used inappropriately.

NODE, definition - a point at which lines or pathways intersect or branch; a central or connecting point.

My interpretation, whether anybody agrees or not, is if when three consecutive shots in .1 increments land into not much more than the size of the bullet at 400Y, "at a central connecting point", that's what I call a node. Or vs what isn't a node, non convergence, the other shots in the ladder test which went 3" vertical.

Call it what you will, a node, barrel timing, bullet exit timing, etc, the phenomenon exists.

Node - also, the other part it, is finding a forgiving powder charge range that allows some leeway in different temps. Little colder or a little hotter, you'll still hit the same spot.

I've never met anyone that works up a load and didn't choose consistent .3 moa vs .5 moa, see how I did that, I included distance, not 100Y groups.
SHP has to do with the size of the target doesn't it?! Like a friend once told me, he'd won the match that day, and claimed the small vertical he was getting with his Dasher got him more edge hits on the tips of the diamonds than the other cartridges he'd used before. In other words, if he didn't get the wind just right, because the vertical was so small in his load, the accuracy was enough to hit the tips at distance vs hitting just over or just under. A few points means the difference between 1st and 2nd sometimes.

There is such a thing as witchcraft, and it doesn't have anything to do with what were talking about here, so you can look the definition up, as long as you're trying to be smart about what word means what.

 

[Deleted member 10043]

Most people are referring to a so-called sweet spot of the barrel not bothering to look up the definition of node. A node is not a phenomenon. There needs to be an intersection. What is your "central connecting point" you are referring to? Where do the bullet lines going down range intersect if your POA is identical for each shot?

 

[918v]

I tried the ladder test one time and it was an epic fail. Max velocity stability fell exactly out of line with max group accuracy.

Pretty common observation. So then what do you do? Pick the least offensive combination? What if there is a point at which the ES is low and the groups are tight? What if you can find that point through node mapping?

There are powder charges that have a great tolerance for oal, meaning that you’ll get sub half minute accuracy with a large oal variance. One oal with that powder charge weight will produce low ES.

The problem is you won’t get there with a common powder measure.

 

[Supersubes]

https://upload.wikimedia.org/wikipedia/commons/8/8c/Standing_wave.gif

 

[Deleted member 10043]

Statistical hit % .3 MOA rifle vs .5 MOA under the same conditions and variables. 500 yards, 5" Target. .7% is rather insignificant considering the shooter behind the rifle is the absent variable. Like I stated, immaterial in the real world.

 

[steve123]

Most people are referring to a so-called sweet spot of the barrel not bothering to look up the definition of node. A node is not a phenomenon. There needs to be an intersection. What is your "central connecting point" you are referring to? Where do the bullet lines going down range intersect if your POA is identical for each shot?

Okay what would be the scientifically correct word to use rather than node, rather than sweet spot?

I see your point, do you see mine? The node is the intersection, each shot in a node has a "velocity spread, right??!!", yet even at different velocities, land in the same place. Though the POA may be the same, not all shots in a ladder converge, some are "out" of a node/not hitting in a central connecting point. In the same ladder tests where 3 shots went into tight vertical, I've seen 3 consecutive shots with unacceptable vertical in comparison.

Looking at it the other way, what word would you use for the rest of shots that did not intersect. I've seen the words "scatter node' used. Maybe that's not correct either.

Phenomenon, definition - ""a fact or situation that is observed to exist or happen, especially one whose cause or explanation is in question"". Now isn't that the perfect way to describe what we're discussing here?!

I've done too many ladder tests with such great results to question otherwise, and if it ain't broke, it don't need fixing.

 

[Deleted member 10043]

The impacts you describe are not a connection point. They are individual shots that have near parallel paths. But their paths don't cross/intersect. Node is a a word that has several meanings in the shooting world for some odd reason.

 

[Lynn Jr]

Wow you guys are really funny.

A ladder or Audette method is extremely fast and easy obsoleting the ocw method by Dan Newberry.

You need a gun and a shooter that can hit the target is the biggest issue I see.
You work in 1% increments.
You are only looking for vertical spread and horizontal spread and muzzle velocity don't matter yet.

With a good gun 100 yards will put most of the shots into a small oblong hole.
300 yards is better.
The muzzle has to be rising or the gun won't group.
Slower shots take longer to exit the barrel so the muzzle is pointed higher.
Faster shots exit sooner so the muzzle is lower.
You want the point where the faster and slower shots converge at the target.
If you can do this with a bench type gun which removes most shooter error the results are fast and easy.
You seat all of your bullets to there longest length which could be deep into the lands or maximum magazine length until you find the powder charge then you play with seating depth in only one direction which is shorter.
If your platform isn't rock solid stay home.

 

[steve123]

Statistical hit % .3 MOA rifle vs .5 MOA under the same conditions and variables. 500 yards, 5" Target. .7% is rather insignificant considering the shooter behind the rifle is the absent variable. Like I stated, immaterial in the real world.

View attachment 7031916View attachment 7031918

That's a little more than a 10th of an moa difference between the two illustrations, do two tenths.

In our world it may be lost in the noise but tell the record holding benchrest shooters that a tenth is immaterial. Like rifles and loads capable of .282" at 600Y, and 1.04" at 1000Y for the long range events, which seems impossible to do. Not to mention aggs in the high .1's in short range BR where the winner is decided by .001's.

I'm not saying having ultimate accuracy is all there is, I'm not saying lowest ES is either, I'm not saying a rifle that does 1/4 moa all day long is the answer, I'm not saying all who have rifles and loads with those three attributes combined will stand the best chance of winning, I'm saying it can't hurt and sometimes it can help.

Lightening things up, when I first started really getting into load development many years ago, I put about 300 rounds down my 6.5-284 and I found the absolute tightest groups that rifle would do. Later that year I got the high score in our local annual 1000Y paper match by 15 points. The barrel was at 1 moa by 800 rounds, lol. I'd never do that amount of work again and to think I've had more accurate rifles since and finished load work in 14 rounds.

 

[47guy]

To add a stick in the spokes you can pick any safe MV you like and just work with seating depth to get an accurate load. From there until the death of the barrel is just chasing the lands. The level of statistical hit probability on any target is immaterial between a .5 MOA rifle and a .3 MOA. It is down to shooter skill and I see way too much bullshit on load development as a means to a dead end easier softer way. In essence, finding the most finicky area is self defeating in the long run.

I’ve been saying this for years....reloading is the most over thought thing EVER!!

OCW..ladder test...10 shot ladder...velocity test...full length size...neck size...neck size then use a mandrel...seating depth test by .001...powder weight by 0.01g...and let’s not forget chasing the 1 hole load...all this shit makes my head hurt ...it’s only as hard as we make it.

 

[Lynn Jr]

Actually once you have done all that work you learn what works and all your rifles shoot better and it's very easy to do.

 

[Deleted member 10043]

So, once you go through all that work you learn what works?

 

[Deleted member 10043]

Even the single holding world record shooter is statistically immaterial compared to the rest of the shooting population. And the only way I can get 2/10th is to change the variables for one rifle. The range and target size are irrelevant variables.

 

[Deleted member 10043]

I'm starting to see where the confusion lies down.

 

[Deleted member 113831]

Whether doing an Audette ladder or an OCW, I never figured out why people start so low. They test the whole range bottom to top. For myself, I know I want the fastest load that will keep me out of trouble in the summer heat. I couldn't give a rat's ass if a load groups if it is 100 fps slower than max. Similarly, I don't give a fuck if it groups when I'm getting hard bolt lift at 40* F.

Once I find what max charge is for my combo, I index off of that and back off the prescribed amount to not lock bolts when it is 100 degrees. That means there is about a .5 grain window I am willing to work with. If nothing presents itself in that window, I look for another powder or bullet.

 

[kthomas]

I used to shoot 10 round ladders, until I found that they didn't prove anything. Load up two ladders of identical charge weights and then try to find any node - you'll see two different results if you run two ladders.

I use ladders to see what charges will get me what velocity, and where I find pressure. From there I load up 3 rounds of each charge I want to pursue, below pressure.

10 round ladders are statistically irrelevant. My nodes are always outside of the nodes produced by a 10 round ladder.

 

[918v]

The easiest thing to do is to do what everyone else is doing.

 

[Milo 2.5]

I can biff shots at any moment, on any given day, a one shot per charge ladder test would be senseless for me to do.

 

[Lynn Jr]

So, once you go through all that work you learn what works?

If you don't learn what works you end up shooting factory ammo. If a Ladder test is beyond you reloading is not for you.

 

[Lynn Jr]

I can biff shots at any moment, on any given day, a one shot per charge ladder test would be senseless for me to do.

Like I said if you and your gear are not up to the job there is always factory ammo.
Do you know how wide the node would be on a 6 BR? And would that be the same on a 300 Weatherby?

 

[Lynn Jr]

To add a stick in the spokes you can pick any safe MV you like and just work with seating depth to get an accurate load. From there until the death of the barrel is just chasing the lands. The level of statistical hit probability on any target is immaterial between a .5 MOA rifle and a .3 MOA. It is down to shooter skill and I see way too much bullshit on load development as a means to a dead end easier softer way. In essence, finding the most finicky area is self defeating in the long run.

Wow you don't know how to do something fast and easy so it doesn't work?
And no you can't pick any safe muzzle velocity and get an accurate load.
You end up with a load that isn't up to your guns potential because you would rather argue than listen

 

[Milo 2.5]

Like I said if you and your gear are not up to the job there is always factory ammo.
Do you know how wide the node would be on a 6 BR? And would that be the same on a 300 Weatherby?

WTF is your problem? I just said a 1 shot per charge ladder test is unrealistic for me to do. You have no idea how I develop a load.

 

[Lynn Jr]

WTF is your problem? I just said a 1 shot per charge ladder test is unrealistic for me to do. You have no idea how I develop a load.

This thread is about doing a ladder test and your not up to the task so why bother posting useless drivel?


This is what you posted and I don't care how you work up your loads.

#40
I can biff shots at any moment, on any given day, a one shot per charge ladder test would be senseless for me to do.

You can start a new thread how Milo 2.5 Biff's his loads so those interested can read it

 

[Jammer Six]

The way I understand it, an OCW ladder has nothing to do with velocity.

 

[Deleted member 10043]

Actually, the thread is about whether or not a ladder test is real or imagined. That sort of leaves it open enough that you shouldn't be telling people that happens to disagree with you to go away.

 

[47guy]

Actually once you have done all that work you learn what works and all your rifles shoot better and it's very easy to do.

lynn this is longrange1 from calguns...i have done all that work and i do know what works...i shoot a 6BRX with no case prep with a 14fps ES that will consistently stack rounds at 1080yds prone off a bipod and my hand....i shot a 6.5x47 before the BRX and had several 40+shot strings with below teens ESs and a few in the singles and again no case prep...i have not done any case prep sense i shot a 260rem and that has to be at least 10yrs ago.

for the shooting i do its not worth the time...i can not hold a 10th of a grain of powder or a .001 neck tension difference off any obstacle or hold well enough to notice in my ESs are low single digits or mid teens...if i was shooting BR or F-class id go FULL OCD!

all this stuff is just to satisfy our OCD looking for the perfect load and believe me i have it to when it comes to reloading...ive just learned to control it...or have i LOL...i just fire formed 200 new cases for my BRX this weekend and am going to run the HBN again...these cases are FULLY prep'd...primer pockets,flash holes deburr'd,necks turned and weighed/seperated with H2o.

i did all this to see if all the case prep will bring the ESs down into the single digits...and to satisfy the OCD...i shot 36 rounds yesterday and 32.9g looks like the new load with an ES of 7fps but 5 shots over the chrony mean nothing to me and im willing to bet from the looks of a fewof the other charge weights i shot that this 7fps goes into the low to mid teens with a larger sample.

 

[47guy]

I used to shoot 10 round ladders, until I found that they didn't prove anything. Load up two ladders of identical charge weights and then try to find any node - you'll see two different results if you run two ladders.

I use ladders to see what charges will get me what velocity, and where I find pressure. From there I load up 3 rounds of each charge I want to pursue, below pressure.

10 round ladders are statistically irrelevant. My nodes are always outside of the nodes produced by a 10 round ladder.

i seen a double ladder shot yesterday that ended up with the same conclusion...no actual usable data it was basically a pressure test.

 

[Deleted member 10043]

So, we have all tried it and that will make those that don't find it useful not guilty of contempt prior to investigation. The problem is it doesn't hold up to scrutiny very well. People that swear by it have a difficult time defending it. Up to and including telling people at some point to just fuck off.