Follow up on reloading for ELR…

[Feniks Technologies]

Also, for example sake, to have a 15es over a large enough sample, your sd would have to be 2.5fps

I’d love to see 100 shot string with a 2.5sd.

As the extreme spread breakdown would be close to

68 shots: 5 fps
27 shots: 10 fps
5 shots: 15fps


That would be an extremely good accomplishment.

 

[badassgunworks]

They are related to what shows up on a target over large samples and long range but not when it comes to what is done in devlopment to obtain one or the other . I have seen tight groups 5 shots with poor standard deviation and seen great standard deviation with bad 5 groups this is why a ladder is preformed to find out that is happening you must know there are different types of ladder tests for different reasons you dont automatically obtain good s.d.'s when you get good group. As they are not related

 

[Feniks Technologies]

Looking at the data it is too perfectly linear to be actual chronological data so this is simply supposed to be illustrative. What I was pointing out was that at 3 shots the relationship to the CI at 25 shots was highly correlated. Looking at Ledzep's data though, his is pretty linear as well. The shoes back to my earlier point that very large sample sizes are unnecessary.

That said, if you have a magneto speed on your gun at all times, why not collect data for analytics.

-Alex

You’re definitely looking at the data wrong.

For example, here is the breakdown of a 5sd shot over a chrono. And the range your true sd will fall in over 95% of the time:


3 shots: 2.6 - 31.4
5 shots: 2.9 - 14.3
7 shots: 3.2 - 11.0
10 shots: 3.4 - 9.1
15 shots: 3.6 - 7.8
20 shots: 3.8 - 7.3
25 shots: 3.9 - 6.9
30 shots: 3.9 - 6.7
50 shots: 4.1 - 6.2
100 shots: 4.3 - 5.8
200 shots: 4.5 - 5.5
300 shots: 4.6 - 5.4

Why this matters?

When you shoot say a 3 shot string test and get one with a 3sd and another with a 7sd, you don’t have enough data to show much of anything. You could pick the 3sd and hope it’s better. But you’re not much better than a coin flip.

10-15 shots is where things start to stabilize.

 

[Feniks Technologies]

They are related to what shows up on a target over large samples and long range but not when it comes to what is done in devlopment to obtain one or the other . I have seen tight groups 5 shots with poor standard deviation and seen great standard deviation with bad 5 groups this is why a ladder is preformed to find out that is happening you must know there are different types of ladder tests for different reasons you dont automatically obtain good s.d.'s when you get good group. As they are not related

He can absolutely shoot .1’s and 2’s at 100/200 yards with a higher than 15es.

BR shooters do it all the time. Hence using powder drops.


Everyone knows at distance the SD matters.

Except the fact that people use that when it suits them. When their numbers aren’t small, the claim positive compensation.

When others numbers aren’t small, they claim it’s their SD that’s going wrong.


But no one ever seems to show up with data on long shot strings. Oddly enough.

This stuff would be incredibly easy to prove otherwise. Yet no one does it.

 

[badassgunworks]

He can absolutely shoot .1’s and 2’s at 100/200 yards with a higher than 15es.

BR shooters do it all the time. Hence using powder drops.


Everyone knows at distance the SD matters.

Except the fact that people use that when it suits them. When their numbers aren’t small, the claim positive compensation.

When others numbers aren’t small, they claim it’s their SD that’s going wrong.


But no one ever seems to show up with data on long shot strings. Oddly enough.

This stuff would be incredibly easy to prove otherwise. Yet no one does it.

The biggest problem is long string large samples prove nothing other the generated heat changes point of impact its somthing we do when devloping loads and in my case . cartridges design and powder types in f class we look for the least amount of vertical on a 20 shot string. reason 20 shot timed venues. But when shooting elr 5 shot to 10 shot is what is needed. so large samples of shorter strings works for what is applicable. Long strings proves nothing other then the nature of the beast and proves nothing about what the rifle is capelable of in your venue. And believe me i dont show up at a match with rifle or load excuses when i can shoot 5 shot groups 10 times in a row and none of those groupes have higher sd then 4 fps then thats what it is for my needs. And thats not chance

 

[Feniks Technologies]

The biggest problem is long string large samples prove nothing other the generated heat changes point of impact its somthing we do when devloping loads and in my case . cartridges design and powder types in f class we look for the least amount of vertical on a 20 shot string. reason 20 shot timed venues. But when shooting elr 5 shot to 10 shot is what is needed. so large samples of shorter strings works for what is applicable. Long strings proves nothing other then the nature of the beast and proves nothing about what the rifle is capelable of in your venue. And believe me i dont show up at a match with rifle or load excuses

This is why David Tubb runs a chrono anytime he is allowed.

He understands that it’s almost impossible to get SD’s low enough to hit targets consistently once past certain yardage and/or target size.

So, when he misses high or low, he has data that tells him if it was the velocity that caused the miss. If it was the velocity, you don’t make a hold change on the next shot.

For example, you shoot a 10 shot 5sd string.

Your sd might be 5, but likely not. It’s going to be somewhere between:

3.4 and 9.1

Which means 95% of your shots could possibly have an ES of 36fps.

If you’re shooting at a distance/target combination that 36fps can miss, and you don’t have a chrono………

When you miss vertically, you can’t reliably decide if you need to adjust your elevation or hold, or just send another one with the same.



There are very, very, very few people who have actual and honest 5sd ammo.

 

[badassgunworks]

This is why David Tubb runs a chrono anytime he is allowed.

He understands that it’s almost impossible to get SD’s low enough to hit targets consistently once past certain yardage and/or target size.

So, when he misses high or low, he has data that tells him if it was the velocity that caused the miss. If it was the velocity, you don’t make a hold change on the next shot.

For example, you shoot a 10 shot 5sd string.

Your sd might be 5, but likely not. It’s going to be somewhere between:

3.4 and 9.1

Which means 95% of your shots could possibly have an ES of 36fps.

If you’re shooting at a distance/target combination that 36fps can miss, and you don’t have a chrono………

When you miss vertically, you can’t reliably decide if you need to adjust your elevation or hold, or just send another one with the same.



There are very, very, very few people who have actual and honest 5sd ammo.

Yes there are many things that effect vertical inc wind . The last time i checked david has only won 1 elr match and most of the time he is in the middle if the score board.
I think Most of the matches allow a chronograph behind the fire line. We could talk about positive compensation even though david agrees with it. but we all know where that will go lol

 

[kennyg]

I've ruined benchrest for more than one person. Guy thinks he's in the .1's-.3's with a 15fps ES and a 20-30 shot set will show otherwise.

I have some handload data, 20 and 35 shot ladder tests with a couple of different cartridges. Somewhere in the .4-.6 MOA range is about as good as I've ever seen with SD's in the 5-7fps range being the best that are repeatable. The powder ladder is less important than the powder type.

Hey, I really appreciate you sharing data that you have spent a lot of time and money to obtain.

Maybe you have answered this somewhere else, but what do you mean by that last sentence? It seems like you are saying that choosing the correct powder can improve accuracy. If so, what process do you recommend for choosing the best powder?

Thanks!

 

[Ledzep]

Hey, I really appreciate you sharing data that you have spent a lot of time and money to obtain.

Maybe you have answered this somewhere else, but what do you mean by that last sentence? It seems like you are saying that choosing the correct powder can improve accuracy. If so, what process do you recommend for choosing the best powder?

Thanks!

It's really barrel and cartridge dependent. Barrels have attitude (different barrels 'like' different things) and powders fit various cartridges better or worse, but in general if you're not getting the level of precision or ES/SD that you want, you're best off changing components. Bullets, even in the same weight class have different bearing surface lengths, ogive/bearing surface angles, etc.. and will produce different pressure vs. time curves that appear to affect accuracy differently.

When you keep the bullets, cases, COAL, and primers the same and swap powders, the biggest change in dispersion I've noted is from swapping different powders. Next biggest is large changes (1gr+ at a time) in powder charge, the next most important thing has been seating depth-- some bullets that matters more/less than others.

That all being said, powders that are popular for certain cartridges are typically popular for a reason. The Hodgdon extreme line has been consistently pretty solid-- Varget is awesome in most anything it makes sense for. The newer RL powders (16, 26) are pretty solid, and even the old ones (15, 17, 23 etc.) perform well but are less temp stable. I haven't messed with Vihtavuori at all, personally, so I can't speak for them but they're popular enough in certain circles they're probably worth looking into if you can find/afford them.

 

[Ledzep]

As far as realistic ES goes, 25-30fps is as good as it gets. If you think you're doing better than that I'd like to see it on a labradar over 20-30 shots. Respectable ES for PRS ranges (400-1400yd) is under 55-60fps with SD's under 12fps.

For ELR MV spread as important if not more important than group size depending on how far you're shooting. The vertical spread from a large ES will out-run the circular dispersion of a 1 MOA load pretty quick if you're talking 1500-3500yd.

 

[Taylorbok]

As far as realistic ES goes, 25-30fps is as good as it gets. If you think you're doing better than that I'd like to see it on a labradar over 20-30 shots. Respectable ES for PRS ranges (400-1400yd) is under 55-60fps with SD's under 12fps.

For ELR MV spread as important if not more important than group size depending on how far you're shooting. The vertical spread from a large ES will out-run the circular dispersion of a 1 MOA load pretty quick if you're talking 1500-3500yd.

Throat in my rifle is pretty well effed now anyways and I have a bunch of ammo loaded so may as well give it a go. I'll post my findings when I have a chance to do the test.

 

[coldboreAU]

@badassgunworks, Feniks Technologies, Ledzep. Interesting discussion, i don't want to say much but it's always interesting to read your posts. Just keep going.

 

[kennyg]

As far as realistic ES goes, 25-30fps is as good as it gets. If you think you're doing better than that I'd like to see it on a labradar over 20-30 shots. Respectable ES for PRS ranges (400-1400yd) is under 55-60fps with SD's under 12fps.

For ELR MV spread as important if not more important than group size depending on how far you're shooting. The vertical spread from a large ES will out-run the circular dispersion of a 1 MOA load pretty quick if you're talking 1500-3500yd.

Hey, I just read through this thread again-thanks for all the great info!

As far as getting that ES number down-what have you found to help the most with that? There are just so many variables, and I am not sure which ones actually matter. Just off the top of my head, there is the powder scale, primers, sorting brass (and if I do sort, is it by weight? volume?) neck tension, flash holes, annealing, sorting bullets for bearing surface length, and the list goes on......

You seem to have a lot of real world experience and the data to back it up, so I was just curious what your thoughts are on this. I apologize if you have already addressed this in other posts. Thanks!

 

[Ledzep]

Hey, I just read through this thread again-thanks for all the great info!

As far as getting that ES number down-what have you found to help the most with that? There are just so many variables, and I am not sure which ones actually matter. Just off the top of my head, there is the powder scale, primers, sorting brass (and if I do sort, is it by weight? volume?) neck tension, flash holes, annealing, sorting bullets for bearing surface length, and the list goes on......

You seem to have a lot of real world experience and the data to back it up, so I was just curious what your thoughts are on this. I apologize if you have already addressed this in other posts. Thanks!

Good lots of a quality powder (unfortunately not all lots are created equal-- as if we needed more knobs to turn) that is a good fit for the bullet weight and cartridge volume you're using, consistent powder charge, and consistent neck tension. Primers may or may not make any difference at all. I've seen some results that suggest more or less oompf from the primer matters, and some that it's basically a wash.

Powder+bullet+cartridge combination seems to be the biggest influence. My load development anymore basically consists of trying different powders and bullets at a single charge weight a grain or two under max charge. Weighing powder charge to +/- 0.1gr is going to get you 98% of the way there. Weighing to the .02gr trends towards sliiiiightly better performance.

Brass prep and brass sorting I feel is largely a waste of time. Myself and a couple people I know have tested this from a few angles and we arrived in about the same place. We've tried sorting by volume, we've tried sorting by weight. We've tried correlating weight and volume (it trends, but it's sort of a loose trend), volume vs. velocity etc... It all comes out in the wash unless you have mixed lots, mixed mfgs, or something fucked/wrong. If you have same-lot cases from a decent mfg. you're not likely to see any improvement by fucking with them. Random samples of same-lot brass show effectively identical ES/SD performance vs. weight sorted, volume sorted, neck turned cases. Same story for firing/annealing/reloading the exact same case 20 times-- MV ES/SD numbers are right in line with unsorted new brass.

Annealing extends brass life. I have not seen it improve ES/SD unless you're talking like 5x+ fired brass that is very work hardened. It's important to have in your toolbox to extend the consistent life of your cases but it won't improve performance over unfired brass.

Neck tension-- insofar as the force necessary to push a bullet into a case or pull a bullet out of a case does have an effect. However... I've only seen it make ES very large in especially bad circumstances (mixing super hard 5-7x fired brass with brand new, for example). I'm anxiously awaiting to see more data coming from the AMP presses with the load cell in it. There may be something there, but I suspect it's small.

Flash holes.. I don't have any real data here.

I haven't messed with sorting bullets in a really long time. Off the top of my head, weight and bearing surface would likely be the biggest contributors to changing MV, but I couldn't tell you how significant they are.

I'll reiterate, though, that I think powder type (Varget, H4350, RL 26, etc. ) for a given cartridge+bullet is what makes the biggest changes.

 

[badassgunworks]

Hey, I just read through this thread again-thanks for all the great info!

As far as getting that ES number down-what have you found to help the most with that? There are just so many variables, and I am not sure which ones actually matter. Just off the top of my head, there is the powder scale, primers, sorting brass (and if I do sort, is it by weight? volume?) neck tension, flash holes, annealing, sorting bullets for bearing surface length, and the list goes on......

You seem to have a lot of real world experience and the data to back it up, so I was just curious what your thoughts are on this. I apologize if you have already addressed this in other posts. Thanks!

load devlopment the single most important thing is finding a charge volume that produces low s.d.'s 2nd is neck tension that includes the exact same seating pressure, neck length trimming . And proper annealing. Applied Ballistics will tell you that all other efforts in case prep will make little difference. Truth is one single operation on brass like lapua brand brass perhaps not but when your using brands like winchester or bertram ect. Stacked tollerances add up.. if it need it do it.

 

[Taylorbok]

I agree with @badassgunworks find a good powder charge your rifle likes with low ES. Accurately measuring that powder charge and neck tension are also the 2 largest contributors I have found. When I removed my expander balls and started using mandrels I found that helped.