Results of Ladder Test and 100-yrd Groups. Where should I go from here?

[Coloradocop]

I'm working on load development for my new AIAX .260 Rem. Currently using:

139gr Scenar bullets
H4350 powder
Lapua brass
Winchester primers.


I'm trying to be economical with components right now, since they're a bit hard to find, and did my initial testing with 5-rounds of 10 different charge weights between 39.0gr and 42.0gr of powder (which is the listed max load in my book). With the exception of the lowest charge interval (which jumped from 39.0-39.6 grains) I used a 0.3 grain charge weight increment for this testing.



Here's how the groups turned out (shot from 109 yards) in VERY windy conditions. Based on these shots it looks like there might be an accuracy node in the area around 41.1-41.4 grains of powder. It's also possible that I shanked a few shots because I was quite cold and wind-battered by the end of this test (started reasonably warm, and the bottom just fell out of the weather that day):





I then went out today and shot a ladder test using this same ammo at 500 yards, in relatively calm conditions. Once again it looks like the only possible node I see is sitting around that 41.1-41.4 grain charge weight (save for the starting charge, which is way too slow).




Some chronograph results over a Magnetospeed (the day I shot the 3-shot groups) gave me the following velocities:


39.0 2545fps Group size: .660"
39.6 2557fps Group size: .534"
39.9 2568fps Group size: .737"
40.2 2594fps Group size: .673"
40.5 2623fps Group size: .411"
40.8 2683fps Group size: .671"
41.1 2692fps Group size: .287"
41.4 2708fps Group size: .270"
41.7 2723fps Group size: .779"
42.0 2738fps Group size: .612"



Based on the limited data I have thus far, it seems like I should start examining the area between around 41.0 and 41.5 grains of H4350. The thing is, in other rifles I've usually found a "node" consisting of at least three charge weights that cluster together, whereas I only have two charge weights looking similar within my testing (that could just be plain dumb luck, too). I'm also noticing that my velocity is only sitting around 2,700 fps, which is about 150fps slower than I was hoping to develop. I've got NO pressure signs at my max load of 42.0 grains, and I know a lot of guys go hotter than 42.0 grains of H4350 while using this bullet (historically I've not been one to exceed the max charge weights listed in my load data though). I should also mention that I haven't really done anything with seating depth yet, and I've got a lot of room to move the bullet forward still.



So, here are the options I see:


1) Shoot another ladder test and some more groups to see if my results repeat on the next go around.

2) Start examining the possible node I've discovered so far, and settle for a moderate load of approx. 2,700 fps.

3) Carefully increase my load to see if I can find a faster node above the maximum I've loaded so far.


Where would you go from here?

 

[chefcam864]

I would increase the powder load, and look for a node up top. I used to put 48gn of RE17 in a 308 and never had any pressure. I know 260 is not a 308, but 17 is damn close to h4350 and 308 is the parent case. I'm not saying put 48gn in there, but I'm sure you could safely find that 150fps you're looking for. Just bump it up slowly, and look for pressure. However, if you're not going to shoot much past 500, I'd stick to what you have.

 

[Coloradocop]

I wonder where I might find the next higher node in this process, and to what degree I can continue to increase my powder charge over the book max? Obviously I'll continue to watch for pressure signs, I just get a bit more worried once I go beyond the theoretically design limits of the cartridge (at least according to my reloading manual).

 

[LawnMM]

Which powder charges had the best SD on the Magnetospeed? I'm in the process of writing an article on doing load development by chronograph rather than some of the ladder test and OCW approaches. The problem with basing things off of where the bullets hit the paper, as you have already realized, is that it tends to be quite subjective. Did you shoot well that day? Was it windy? Were you cold and your hands shaky? Are you as consistent a shooter as you want to believe? Etc.

None of that is a knock, its just my attempt at pointing out some of the variables with those methods. I've yet to see somebody offer up a load for a cartridge that shoots in the single digit standard deviation that won't group on paper in the hands of a competent shooter. Obviously you want velocity, I'd pick the fastest powder charge with the best SD numbers and do some extra work around that. For example, your 42gr group was buying you 2730fps, say the SD was 12 and was the fastest charge with the lowest SD, I'd load 5 at 42gr, 5 at 42.1, 5 at 41.9, and see if moving up a tenth of a grain brings the SD into single digits. You hit 9 or less I'd call it good. PM me and I'll shoot you my number if you want to chat about it.

How many rounds through the barrel? What barrel length? Your velocity, and powder charges, are still pretty conservative. My 6.5CM picked up about 150fps in MV in the first 200 rounds through the barrel.

Rich

 

[chefcam864]

Which powder charges had the best SD on the Magnetospeed? I'm in the process of writing an article on doing load development by chronograph rather than some of the ladder test and OCW approaches. The problem with basing things off of where the bullets hit the paper, as you have already realized, is that it tends to be quite subjective. Did you shoot well that day? Was it windy? Were you cold and your hands shaky? Are you as consistent a shooter as you want to believe? Etc.

None of that is a knock, its just my attempt at pointing out some of the variables with those methods. I've yet to see somebody offer up a load for a cartridge that shoots in the single digit standard deviation that won't group on paper in the hands of a competent shooter. Obviously you want velocity, I'd pick the fastest powder charge with the best SD numbers and do some extra work around that. For example, your 42gr group was buying you 2730fps, say the SD was 12 and was the fastest charge with the lowest SD, I'd load 5 at 42gr, 5 at 42.1, 5 at 41.9, and see if moving up a tenth of a grain brings the SD into single digits. You hit 9 or less I'd call it good. PM me and I'll shoot you my number if you want to chat about it.

How many rounds through the barrel? What barrel length? Your velocity, and powder charges, are still pretty conservative. My 6.5CM picked up about 150fps in MV in the first 200 rounds through the barrel.

Rich

Not to say your experiment doesn't have merit, but a low SD is important for maintaining tight vertical at distance, not for shooting tight groups. I have had loads with an SD of 7 shoot from 12:00 8-ring to 6:00 8-ring at 300 yards. Why? Because I was in the worst possible node I could have been in. A buddy went to the worlds/nationals at Raton this year, and the guy he ended up scoring for was barely holding 9-ring elevation at 1k yards. His ammo had an SD of 3... I'm not trying to be a jerk or anything, it's just that my personal experience, and the experiences of some very high level shooters I know, seem to indicate that a low SD is not NECESSARILY an indication of a good load. When I'm working up loads for LR, I look at group size AND SD. At distance, one without the other is just probably not going to be the best load. Harmonics are a very critical factor, and that's precisely what you're looking for when you shoot a ladder test. A low SD is definitely critical at long range, but a consistent bad load is still a bad load. However, I'm an open minded person and if your research shows me to be wrong, I'll accept it.

As to how far you can push your load beyond book max... That's up to you. I'd personally load until I found pressure, to establish a ceiling. Every rifle is different, and only through sound reloading practices can you discover your rig's pressure limit. I'll add this: the max velocity listed in the books tends to be a better indication of max pressure than the max charge. If you're at the velocity listed at the top of the load manual, your probably getting close.

 

[MetroJethro]

Which powder charges had the best SD on the Magnetospeed? I'm in the process of writing an article on doing load development by chronograph rather than some of the ladder test and OCW approaches. The problem with basing things off of where the bullets hit the paper, as you have already realized, is that it tends to be quite subjective. Did you shoot well that day? Was it windy? Were you cold and your hands shaky? Are you as consistent a shooter as you want to believe? Etc.

None of that is a knock, its just my attempt at pointing out some of the variables with those methods. I've yet to see somebody offer up a load for a cartridge that shoots in the single digit standard deviation that won't group on paper in the hands of a competent shooter. Obviously you want velocity, I'd pick the fastest powder charge with the best SD numbers and do some extra work around that. For example, your 42gr group was buying you 2730fps, say the SD was 12 and was the fastest charge with the lowest SD, I'd load 5 at 42gr, 5 at 42.1, 5 at 41.9, and see if moving up a tenth of a grain brings the SD into single digits. You hit 9 or less I'd call it good. PM me and I'll shoot you my number if you want to chat about it.

How many rounds through the barrel? What barrel length? Your velocity, and powder charges, are still pretty conservative. My 6.5CM picked up about 150fps in MV in the first 200 rounds through the barrel.

Rich

Rich,

You bring up an interesting point. I do not want to highjack this thread. I am pretty new to rifle reloading and I have wondered how much my shooting skill (or lack there of) influences my decisions on which loads are more accurate. Am I correct in saying that you think the SD of a particular loads MV is a better indication of that loads potential accuracy than the group size? If so, than we could use the SD and a sanity check on our group size.

 

[Warbone]

I have a savage 260 remington with 26" shelin barrel. Just from my experiance with h4350, 140g amax, 140g berger vld and hybrids, and 139g scenars nodes have been at 41.3-41.4, 42.7-42.8, and 43.9-44.1. I have gone up as high as 44.5 wiht no pressure signs. I did both ladder test and OWC to find these nodes. I have stuck with the 42.7 load and fine tuned with seating depth, less pressure than the higher node for longer brass life, and they all run between 2775-2825 fps. Your rifle seams to be shooting very simalar to mine. Try the 42.7 node. Work up to it ofcourse.

 

[LawnMM]

Not to say your experiment doesn't have merit, but a low SD is important for maintaining tight vertical at distance, not for shooting tight groups.

I would say its important for both, wouldn't you? You aren't going to get a tight group if your velocity is changing by 30-40fps from one shot to the next.

I have had loads with an SD of 7 shoot from 12:00 8-ring to 6:00 8-ring at 300 yards. Why? Because I was in the worst possible node I could have been in. A buddy went to the worlds/nationals at Raton this year, and the guy he ended up scoring for was barely holding 9-ring elevation at 1k yards. His ammo had an SD of 3... I'm not trying to be a jerk or anything, it's just that my personal experience, and the experiences of some very high level shooters I know, seem to indicate that a low SD is not NECESSARILY an indication of a good load.

You aren't being a jerk, we just disagree. Your experience is quite different from mine. I've yet to personally witness a load with low numbers perform badly. In fact, you are the first person I've ever even heard claim to have seen such a thing.

When I'm working up loads for LR, I look at group size AND SD. At distance, one without the other is just probably not going to be the best load.

I would agree. The problem is we disagree on what's more important. I say the SD is the more important variable. You can NOT have a good group at say 1000 yards with a crappy SD number, it just isn't going to happen. You are suggesting that you can, whether on purpose or not. Basically, you can't have it both ways. While it may be possible to worm a half decent group or even a great one with a great shooter at 100 yards despite a crappy SD, you aren't, even in capable hands, going to produce a good group at 1000 with a crappy SD. The tight SD is essential.

Harmonics are a very critical factor, and that's precisely what you're looking for when you shoot a ladder test. A low SD is definitely critical at long range, but a consistent bad load is still a bad load. However, I'm an open minded person and if your research shows me to be wrong, I'll accept it.

I appreciate the open mind. I think this is where our opinions differ. I don't think you can have a 'consistently bad load'...if that makes sense. Consistency is the name of the game. Again, and you said it yourself, a low SD is critical at long range. So, even if we agree on nothing else, why not START by finding the good SD numbers and THEN evaluate whether or not the precision element is satisfactory. Bryan Litz did almost a chapter specifically on Velocity Changes and Velocity Consistency as variables in long range accuracy in 'Accuracy and Precision for the Long Range Shooter.' The SD numbers are critically important at distance or the vertical dispersion will give you misses as the POI fluctuates. If we can all agree that having those tight SD numbers is non negotiable, then why not start there with load development? Why monkey around with group sizes at statistically insignificant ranges. Its a waste of time and reloading components. I'm going to have load development done in two days and less than 50 rounds fired if this works the way I suspect it will. I've already done the development with rounds to spare, I'm just going to confirm the results on a separate chronograph and then load more to test group size and down range performance.

As to how far you can push your load beyond book max... That's up to you. I'd personally load until I found pressure, to establish a ceiling. Every rifle is different, and only through sound reloading practices can you discover your rig's pressure limit. I'll add this: the max velocity listed in the books tends to be a better indication of max pressure than the max charge. If you're at the velocity listed at the top of the load manual, your probably getting close.

I'm not necessarily advocating pushing beyond book max, just most books are overly conservative, I find the data published by the powder manufacturers to be a truer representation of what's attainable.

Rich,

You bring up an interesting point. I do not want to highjack this thread. I am pretty new to rifle reloading and I have wondered how much my shooting skill (or lack there of) influences my decisions on which loads are more accurate. Am I correct in saying that you think the SD of a particular loads MV is a better indication of that loads potential accuracy than the group size? If so, than we could use the SD and a sanity check on our group size.

Yes and No. What I'm saying is that a lot of the common reloading methods were pioneered by guys that shoot bench rest, f class, nra bullseye, etc. Those are guys that put tens of thousands of rounds down range a year. I'm not saying a pro can't get behind a rifle, fire a group, and make an educated analysis of that load's precision potential. What I'm saying is that most of the rest of us probably can't because we aren't nearly as consistent shooters as we want to believe. If you take a novice shooter that really doesn't have a good grasp of the fundamentals and say, yeah go shoot some groups and pick the powder charge with the best one, you are setting the guy up for failure. He might by pure luck put a group together at 100 yards, where factors like muzzle velocity and barrel harmonics are less significant, when in reality that powder charge wouldn't produce anything remotely decent at significant distance even in the hands of a professional.

Its like when your wife looks at herself in the mirror and says she thinks she's lost weight, its purely subjective speculation right? So confirm it with some scientific, like a scale. Or in our case, a chronograph. I'm a better shot than many and a lot worse shot than plenty but I'm very good at self critiquing and I can usually tell when the group down range is my fault, or something else. More often than not, its me, I'm rusty, or cold, or tired, or whatever. The chronograph doesn't lie, its either a consistent load or its not. This notion that you can have a 'consistently bad' load is what I'm challenging, I don't think that's possible and there are plenty of other variables I could point out that would account for any issues that arise. In Chefcam's example he had a load with an SD of 7 that went from 12 to 6 O' clock on the 8 ring (I assume F Class Target) at 300 yards. That's a difference of almost 9 inches at 300 yards. Could it have been a 'consistently bad load'? Maybe, I'd like to spend some time at a range with somebody that has something like this to see it myself. Just playing devil's advocate and not trying to take shots at you Chef, but could it also have been stress or pressure from competition? Wind buffeting your body? Shaky hand from cold? Maybe a little shaky and hypoglycemic from skipping breakfast? Jerking the trigger? Poor follow through? Not breaking the shot consistently in the breathing cycle? Etc etc?

There are so many SHOOTER based variables that come in to play I'm finding it hard to believe that all of those were dead nuts and we somehow have a load that releases and flies consistently but somehow groups poorly at distance? Why do guys check their loads at distance in the first place after initial workup? To see if a good group at 100 is still tight at 600 because that's a more significant distance right? Even with a crappy load in capable hands you might get a decent group at 100, but surely not at 600. Well if I have to have a tight SD to even have a chance at a good group at distance, doesn't that make the SD a good jumping off point for testing at distance? So why screw around doing a half dozen or dozen 3 or 5 shot groups at 100 with ladders and OCW when I can fire two over a chronograph and pick the best velocity with the lowest SD? Then put a few strings of 5 together over a chronograph in that neighborhood and if I still get good chrono numbers THEN check and see how it groups at 100 and 600?

I'm following my own approach for load development with the 6.5CM as part of the article. I'm going to see how it does at 100 and then I'll check it at 600 using nothing but chronograph numbers to develop it initially. Based on my own reloading experience I'm honestly going to be shocked if it doesn't produce. The SD is 7FPS. I've not had a single digit SD load that wouldn't produce a half MOA group at 100. Unless I was tired, hungry, cold, rust, blah blah blah. I'd be willing to bet if I gave Frank my gun and ammo and let him shoot it there wouldn't be an issue. Maybe I'll see if he's interested in that, if he's not there's plenty of Colorado people I can probably get that shoot tighter than I do to test the theory.

 

[chefcam864]

I guess the simplest way of putting it is this: All good loads for LR have a low SD, but not all loads with a low SD are good at LR, or any distance for that matter. As I said in my earlier post, a low SD without the accuracy to go with it is not going to be a good load. Here's a hypothetical: I'm testing two loads at 300 yards and one load averages 1.25" with an SD of 4 while the other averages .75" with an SD of 8. Both of those are supremely accurate(.39 & .24 moa respectively), and beyond the capabilities of the average rifle/shooter. Which one should I choose? Personally, I'm going to go with the load that shot .75". Why? Because in my experience, a load with an SD of 8 will still hold 10-ring (1 moa) at 1k, and the load's superior accuracy will better serve me than the other's superior consistency. You see, I never said SD wasn't important, just that it's secondary to accuracy. Like everything else, a shooter may need to compromise. Which way he goes will be based on his experience and input from other shooters etc. I'm not saying that a load that shoots .125 moa at 100 yards with an SD of 20 won't suck at 1k. It will! My point is that a low enough SD is so damn easy to come by I don't even worry about it until I know how a particular combo shoots. You want low SD? It's simple. Use an appropriate powder that fills most, if not all, of the case capacity and gives the velocity you need. If that doesn't do it, switch powders.

Another reason I don't look for SD before accuracy is economy. The standard deviation of 5 shots means nearly nothing. It can give you a decent indication of how consistent a load will be, but n=5 is not nearly enough to obtain an accurate measurement. Once I know a load shoots, I'll put at least 30 over the chrono, get a real mean, SD, ES, and variance for that load in those conditions, and call it done.

I'm not trying to argue LawnMM down, I'm sure he is a fine shooter and is basing his assumptions off of his own personal experience. It's just that I have had several personal experiences, that make me believe that a low SD is not, in and of itself, an indicator of good performance. However, I will say that I have NEVER had a load, with an SD<10 that shot little bugholes at 100, not perform at 1k. The Chrono IS an invaluable tool for predicting what an ACCURATE load will do at distance. If all one has access to is a 100 yard range, then he can certainly use the chrono to validate his load's potential, before investing the time and $$ going to a match, and have a good degree of confidence that it will perform.


As I stated earlier, bad load that is consistent is still a bad load. Refer back to my story about holding 2 moa elevation at 300 with an SD of 7.

To the OP, I'm sorry if I hijacked your thread. Just keep working up loads until you run into pressure. Just be aware that atmospheric conditions can put a load that was safe at 70 degrees over the line at 95 degrees. I shoot F-TR, and routinely see guys press the limits (200gn @2775 in a 308) without issues. I'm not saying that it's smart, or even necessary, but I've seen it done many times. One last tidbit: never give up accuracy for a little bit of speed.

 

[LawnMM]

Its a good discussion, no offense taken from any of it. I'm the flip side of your coin. I start with the SD and I've never had a low SD that didn't perform. You start with group size. The point of this isn't necessarily to change the face of reloading, that's not what my little experiment is about. Its about another tool for the toolbox, particularly one that might help newer shooters/reloaders get better results as they learn. If all else fails, why not try it for giggles? If I had a way to produce a load with a low SD that shoot like crap farther out I would, either way the information is valuable. I suppose that may happen as I finish my experiment and the article that goes with it. We'll see, should be some good reading and ruffled feathers & drama either way! =)

 

[majohnson2]

Coloaradocop
My AE has a Bartlien barrel and to date the best load has been just shy of mid of way on the loading scale. It sound like a tough day at CRC.

 

[mdmp5]

Go with a hotter load if you can.

 

[Jcub]

I personally, only do ladder test's past 600 meters. If that's the distance you're shooting, then that's the distance you need to be testing at. YMMV.

 

[chefcam864]

Its a good discussion, no offense taken from any of it. I'm the flip side of your coin. I start with the SD and I've never had a low SD that didn't perform. You start with group size. The point of this isn't necessarily to change the face of reloading, that's not what my little experiment is about. Its about another tool for the toolbox, particularly one that might help newer shooters/reloaders get better results as they learn. If all else fails, why not try it for giggles? If I had a way to produce a load with a low SD that shoot like crap farther out I would, either way the information is valuable. I suppose that may happen as I finish my experiment and the article that goes with it. We'll see, should be some good reading and ruffled feathers & drama either way! =)

I agree it's worth pursuing. Data is always a good thing to have. It may turn out that experiences like mine are aberrations, and you may end up turning guys on to a quicker, easier way to develop loads. I'd be interested to see the results. I'm fortunate to be able to pick the minds of a few world class shooters, and the one thing I've taken away from all those conversations is that there are 1000 ways to skin this accuracy cat. One guy tells me there is no advantage to turning necks and running a tight neck chamber, while the other swares by it! They're Both high masters and unbelievably good shooters. Who do you believe? Who knows, because they both win. That's just one of dozens of examples I can think of. The point is guys win using all kinds of different techniques. You gotta try things, and see what works. It's all part of the fun/satisfaction

 

[Coloradocop]

Thanks for all of the replies, everyone. I do appreciate everyone's input on this subject!

Which powder charges had the best SD on the Magnetospeed? I'm in the process of writing an article on doing load development by chronograph rather than some of the ladder test and OCW approaches. The problem with basing things off of where the bullets hit the paper, as you have already realized, is that it tends to be quite subjective. Did you shoot well that day? Was it windy? Were you cold and your hands shaky? Are you as consistent a shooter as you want to believe? Etc.

None of that is a knock, its just my attempt at pointing out some of the variables with those methods. I've yet to see somebody offer up a load for a cartridge that shoots in the single digit standard deviation that won't group on paper in the hands of a competent shooter. Obviously you want velocity, I'd pick the fastest powder charge with the best SD numbers and do some extra work around that. For example, your 42gr group was buying you 2730fps, say the SD was 12 and was the fastest charge with the lowest SD, I'd load 5 at 42gr, 5 at 42.1, 5 at 41.9, and see if moving up a tenth of a grain brings the SD into single digits. You hit 9 or less I'd call it good. PM me and I'll shoot you my number if you want to chat about it.

How many rounds through the barrel? What barrel length? Your velocity, and powder charges, are still pretty conservative. My 6.5CM picked up about 150fps in MV in the first 200 rounds through the barrel.

Rich

Hey Rich!

I know what you mean about shooter-induced issues… I tried my best to give myself a good run on that load development, but the wind and cold were a bit of a challenge (no one shoots their best when they are shivering, that's for sure).

I kind of short-changed myself on the chronograph run… I was trying to conserve ammo while doing my initial load development, and another 'hide member had a Magnetospeed available on the day that I was shooting my groups. I ended up just running one round of each powder weight across the chronograph, just to get a rough idea of how fast the loads might be moving. The results came out about as expected (when looking at the spread across the 10-shot sample as a whole), but I obviously don't yet have the data available to see which charge weights produced a lower velocity SD. I might have to beg some more chronograph time the next time I hit the range, just to get a more thorough understanding of how consistent each load is.

I'm glad to hear that you gained some velocity as your barrel broke in! Hopefully I'll get a bit more myself… my barrel is a 24" Bartlein barrel, and has had a total of 80 rounds through it so far, with only 50 of those being hand loads. The rounds I put over the chronograph were #57-67, so I'm hoping I see a bit of velocity increase still.

 

[CK_32]

46.1 and 46.4 seem to be the obvious load.

Now load away and play with seating depths.

 

[afate45]

No need to beg, you can use my Magnetospeed any time Shoot me a text when you want to head out again. If we can't align schedules any time soon and you need to get out, let me know and I can loan the Magnetspeed.

I can't remember if I mentioned this or not in our discussions, but I get about 50 more fps than you with 42.0gr. Probably due to what Rich said, round count. I'm up to about 350 or so now.

By the way...are you going to the precision rifle match at CRC on Feb. 22nd?

 

[Coloradocop]

No need to beg, you can use my Magnetospeed any time Shoot me a text when you want to head out again. If we can't align schedules any time soon and you need to get out, let me know and I can loan the Magnetspeed.

I can't remember if I mentioned this or not in our discussions, but I get about 50 more fps than you with 42.0gr. Probably due to what Rich said, round count. I'm up to about 350 or so now.

By the way...are you going to the precision rifle match at CRC on Feb. 22nd?

Thanks a lot, Andrew, I appreciate it! We'll definitely have to get out to the range again soon.

Also, if I were to gain that 50fps you noticed with the barrel breaking in, and then find another node somewhere in the mid-42's, I'd probably be getting pretty close to that 2,850fps I was hoping for.

I'll let you know on the CRC match. I just scored a promotion at work, and my assignment change (next week) is going to result in some scheduling changes as well. In typical government fashion, they've yet to tell me what those changes are!

 

[afate45]

I'm in the process of writing an article on doing load development by chronograph rather than some of the ladder test and OCW approaches

I am definitely staying tuned for this article...very intrigued.


Kevin,
I'm trying to remember exactly, but I think Dan Newberry stated that you'll find nodes approximately 3% apart. I have found this to be very true in my AE. 40.7gr is that insanely accurate load we talked about, and I remember back when I shot groups with 42gr I had similar results...which is just over 3% above 40.7gr (41.9 would be exactly 3% above). I'm very curious to see if you find a node between 42.2 - 42.7.

 

[CK_32]

Exited for so many spelling errors due to Auto Correct.


The chrono theory is nice, in theory. But anyone that has used a chrono or many knows chrono's are off and just ball parks. You line up 5 of the best quality chrono's all in a row and each one will give you a different number.


So the chrono testing is broke from the start. Not the theory of testing it self, but the chrono technology is not there yet to where you can pull his off. So in all the OCW/Ladder variables from human error are no greater than the variation in the ball park numbers from a chrono. Maybe in 20 years when chrono's are exact it could be done but they are too "about" to creat a solution.

At least with OCW/Ladder testing you have an answer and have he find the problem in which it came from from a multiple choice.

With a chrono your basically going off, we'll the answer might be 5, and the problem it came from is one of these problems in chapter 4 of his math book.

Basically trying to build a shed with a crooked ruler. Again nice in theory and he might have something. But until chrono's become exact again it's no more than a HUGE guess and theory.

Some chrono's vary 30 to 80fps from the same shot.

 

[LawnMM]

The chrono theory is nice, in theory. But anyone that has used a chrono or many knows chrono's are off and just ball parks. You line up 5 of the best quality chrono's all in a row and each one will give you a different number.

As opposed to five shooters on the line that will all have perfect trigger presses and shoot POA/POI repeatably and consistently?

So the chrono testing is broke from the start. Not the theory of testing it self, but the chrono technology is not there yet to where you can pull his off. So in all the OCW/Ladder variables from human error are no greater than the variation in the ball park numbers from a chrono. Maybe in 20 years when chrono's are exact it could be done but they are too "about" to creat a solution.

That's your opinion. Like I said, I'm sure this will ruffle some feathers when its done. You don't have to like it, my only request is keep an open mind and maybe try it yourself before you write it off. I would say the human error variations are significantly greater than any error with the chronograph. Your experiences don't mirror my own. I find that quality chronograph's tend to be quite consistent. If you are using a bargain unit, yeah maybe its an issue, but chrono's have come a long way since a lot of these methods were developed.

At least with OCW/Ladder testing you have an answer and have he find the problem in which it came from from a multiple choice.

I don't know what that means, your phone totally garbled your message.

With a chrono your basically going off, we'll the answer might be 5, and the problem it came from is one of these problems in chapter 4 of his math book.

?!

Basically trying to build a shed with a crooked ruler. Again nice in theory and he might have something. But until chrono's become exact again it's no more than a HUGE guess and theory.

Some chrono's vary 30 to 80fps from the same shot.

What are you basing that on?

 

[Graham]

Where would you go from here?

I would go to 300m, and I would forget about any ladder test results at 100m.

 

[918v]

What's the barrel length and are u running a brake?

 

[918v]

Nevermind, I just saw your barrel length. If your OAL is 2.830", then you are in the node at 41.1grs and the velocity is correct. I'd play with primers at this point to see which gives the lowest ES and go with it.

 

[CK_32]

I'm basing my whole post on people I know who have messed around with top dollar chrono's at our range days 3 to be exact, which sometimes would vary 20FPS between one chrono and another of the same brand and distance. Even from the same loads or same shots when they stacked them behind each other to all 3 give a reading from the 1 shot.


I'm not bashing your method at all and would love another load development proven. But again your theory is way far ahead of chrono graph accuracy right now.

And as for tech advancing we did this maybe all of 2/3 years ago idk if it's advanced that much. All I'm saying until chrono's aren't exact you can't really find a for sure answer with about numbers.

OCW/Ladder base their results off of the bullet. Like people say "the bullet doesn't lie." Where your basing your off the start with "about" information. Again if you get a 100% guaranteed chrono you have something. Until that happens your on a hard mission for your self.


Either way I wish you good luck. Hope to see it cemented soon. Wouldn't mind using it if it works. But I'm just not holding my breath. Again, not belittling your theory but the technology of your test equipment.


I feel you would save a lot of time and effort getting a HIGH speed camera and do mathematical speed measurements as they do in mythbusters with a relative background to calculate the projectiles speed it self, almost exact as long as the math is correct. Than rely on a chronograph that May or may not be spot on every bullet.

 

[LawnMM]

Its a good discussion all around, no offense taken. Again, lets return to an earlier point. You MUST have a tight SD to have a group that performs at distance. Everyone agrees on that right? If you shot to shot SD is 40fps good luck at 1000 yards, right? So is it not a logical approach to at least START with good SD numbers and go from there? As opposed to starting with things like bullet impact on paper that are highly subjective and easily influenced by shooter inconsistencies?

I really want to see this. Somebody develop a load with a single digit SD that doesn't group well at 100 or 600 yards...

I'm not knocking OCW or Ladders, they have their place, I've used them myself. My point is that they aren't quite what I'd call an objective test, and in the hands of a novice, can be downright misleading. Why don't we all let go of the past and start with what we all agree on. You 100% MUST have a tight SD if you plan to shoot to distance. I'm not done with my article or my testing and even when I am there will still be purists and holdouts that don't agree. I think we all can agree on the fact that you must have a tight SD in the single digits for a load that performs at distance, without it you are wasting time and components. So lets take a step in a modern direction and start with what we know...we know we need a tight SD, so start with something akin to a ladder and see what kind of SD numbers you get. When you see something promising, refine it, shoot 10 or 20 or 100 or whatever length strings make you sleep easily at night to determine if its still a statistically tight SD. Then if it doesn't group well you might have to try elsewhere. I don't think anybody is going to develop a load with a consistency in single digits that doesn't group.

Honestly, I think its a red herring. Or a unicorn. We've heard of it, but who's actually seen it? I really hope somebody in Colorado has a load recipe that will produce single digit SD numbers but won't group well no matter who's behind the rifle, it would make ME sleep better.

 

[918v]

Its a good discussion all around, no offense taken. Again, lets return to an earlier point. You MUST have a tight SD to have a group that performs at distance. Everyone agrees on that right? If you shot to shot SD is 40fps good luck at 1000 yards, right? So is it not a logical approach to at least START with good SD numbers and go from there? As opposed to starting with things like bullet impact on paper that are highly subjective and easily influenced by shooter inconsistencies?

I really want to see this. Somebody develop a load with a single digit SD that doesn't group well at 100 or 600 yards...

Tight ES is desirable. Absolutely.

The problem is that loads that produce a tight ES today don't always produce a tight ES the next day. And if those loads are not on the node, they will not group well on the next day either. Whereas the loads that are on the node will indeed group well on the next day and the day after.

I think it is better to develop several accurate loads using OCW and then pick out the one with the most frequently occurring tight ES. This is doable through the testing of different primers.