Honestly I rarely look at the SD, the ES is all I watch most of the time, and if there's an anomaly I'll try to figure out what was different . Going from the Hellfire to the Barrett was a total kick in the nuts getting the ES down under 10. I shot the Hellfire Thursday at King to foul the barrel and check speed before I let Alex shoot it in the match and as always I had a sub 6fps ES across 15 rounds at the zero range , which is how that rifle has always been.
- Thread starter Jlawsonb16
- Start date
This is a gross misunderstanding of how SD/ES works. ES is literally never used in any other industry but the rifle industry and for good reason. Your ES is always going to be 6x your SD for close to 99% of shots in the long run and every once in a while it will be 8x your SD.
Using the word "anomaly" in conjunction with extreme spread is just very, very bad. As you have unrealistic expectations what your ES should be, so you're going to call something an anomaly that actually isn't.
An ES of 9.9fps across 19 rounds that have an SD of 6fps is actually the anomaly.
With 19 rounds and 6fps.....your SD can be up to an 8.9sd 95% of the time and as low as 4.5fps.
Which means up 99.7% of the time, your ES will be somewhere between 27 and 53 fps. Anything lower or higher than that is actually the anomaly you speak of.
I mean this with absolutely no offense, but your success at ELR is *despite* your knowledge of how these statistics work and not *because* of it.
Standard Deviation and Extreme Spread are stats that are borrowed from mathematic/statistics and used in the rifle industry.
You can't just make up your own definitions and uses. Doesn't work that way and you're not actually getting the data you think you are using those interpretations.
When you google "extreme spread".....you almost only see rifle related topics pop up. This is a big clue how bad of a statistic it really is.
You can't just make up your own definitions and uses. Doesn't work that way and you're not actually getting the data you think you are using those interpretations.
When you google "extreme spread".....you almost only see rifle related topics pop up. This is a big clue how bad of a statistic it really is.
Sometimes it’s just measurement error. I had my LR & Magnetospeeds throw some weird measurements before. Plus, the code in these units can do some funky things. Bugs do appear from time to time.
I'd be double and triple checking my chrono if I had a 19rnd string with a 6sd and a 9es.
Can you post all 19 shot velocities? So the SD can be checked manually. That's going to be a pretty rare occurrence, if it's even possible.
Can you post all 19 shot velocities? So the SD can be checked manually. That's going to be a pretty rare occurrence, if it's even possible.
Anything I take to a match has never had an extreme spread of more than 10 fps across 10-15 rounds , whether my interpretation is wrong or not my shit works . The highest ES I've had was on a PDM at KO2M 2021 and it was 14fps across 10rds on the AB mobile lab with a 375 Hellfire barrel that was almost gone. Like I said earlier I'll have to look at the archived chrono data because I never look at SD , all I watch is extreme spread.
Oh I don't disagree with what "works." You obviously have your brass prep down (I agree that is where most of the reduction in SD comes from).
But realize if you actually have a real to life ES of 10, your SD is less than 2fps.
I know , I know , it's only three shots , but this is one of the only pictures I have of the magnetospeed with SD shown .
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The problem with a sample of 3 is that asymptotic assumptions don’t kick in at that small of a sample. Meaning the sample statistics don’t converge in distribution or probability to the population statistics. So, the estimations can be poor or unrealistic.
HOWEVER, I have found that many good reloaders and shooters are able to reliably estimate their MV & SD regardless of theological assumption violations. So, chances are you’re doing everything right.
HOWEVER, I have found that many good reloaders and shooters are able to reliably estimate their MV & SD regardless of theological assumption violations. So, chances are you’re doing everything right.
2021 with Paul and Brian prior to Clarks knob we tested 3 Labradars and a magnetospeed at the same time for comparison sake on my 375 Hellfire running 400 Lazers at 3280fps . Across 9 rounds 3, 3 shot strings all four chronos showed 2fps ES .
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You can still use it to eliminate things. Which I think is what you're already doing. If your target ES is single digit, anything over that goal gets scrapped or you attempt to fix/improve.
But, what is extremely important is to realize when your ES is giving you the wrong story. Like the example of 19 shots with a 9es and a 6sd.
Ignoring that's likely not possible and there is a small error in the coding for that string.....your ES is using 10% of the available data and the sd is using 100% of the data. Meaning your ES is going to be much closer to 24fps if you were to continue shooting that ammo longer strings over the chrono (obviously this is assuming the 6sd was calculated properly by the instrument).
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Chances are , lmao ,I might be. And as I mentioned that was about the only picture of an SD readout that I had. The amount of podiums and big match wins the last few years has brought me seems to say what I'm doing must be close to being right .
We’re FB friends I believe. Unless there’s another ELR shooter with the last name Wolf. I know you’re legit.
It's probably me, lol . And I'm getting the hell off of here to go load and foul the barrel of the Barrett so I can head to Black Bear . 19 hour drive Thursday to go shoot 30 rounds and drive 19 hours back home.
Nice shooting!
Basic, lol. I sort all of my brass by weight prior to first firing, all of the 50bmg primers are sorted, gm215m I don't bother. Bullets are loaded by lot number. After the first firing before I decap I sort all of my brass by volume with isopropyl alcohol. Decap, dry tumble with a mixture of walnut and corncob, rinse with alcohol and wipe clean. Anneal every firing, fl size with the minimum shoulder bump . Up until the 3rd firing I usually don't bump the shoulder unless the bolt is closing with resistance. On the Hellfire I try for .0015-.002 neck tension. I check necks and don't turn unless there's an inconsistency and then only minimal and If it's way out it gets thrown away. I don't use any bullet lube and seat everything but the Barrett with a modified Vickerman seating die that I made the seating stems on the lathe from old barrels , it gives me less run out than about anything I've used . Nothing fancy and it works.
Well dang, thats all I ever focused on was ES and here as well was humbled over the very low numbers on the 416, now after reading all of this I don’t even want to consider the Applied Ballistic lab report after sending 10 rounds past their Doppler, all their dang report focuses on is extreme spreads in both speed and BC. Honestly Justin I ain’t changing my ways hope to cross paths again soon.
JH
JH
The mobile lab with the PDM on the Hellfire was a definite game changer with the drag curve, there are multiple shooters still running my PDM for the 550 Lazers. I know it can definitely be heartbreaking when the load looks good and the BC/SD is all over the place when the barrel is gone.
My numbers are good and a solid barrel so we will be fine, I don’t care about the chatter here as long as I keep seeing very low ES numbers thats all I look at. Funny I never got into SDs I’m just looking forward to the day when work is no longer a issue and the gun travels more as in the past, I’m just struggling telling the folks this old guy is ready to retire because of all the farm machinery dealers I call on are close friends now.
See ya in 2024
Jeff Heeg
My match schedule is going to be lighter next season , but I'll still be hitting quite a few, look forward to seeing you at any we cross paths at.
It's funny that you're talking bad about the CCI primers, the Barrett MradELRs that finished in the finals at KO2M were running cci35s , my personal rifle had an ES of under 9.9 fps across 20 rounds the day before we shot the prelims and finished in second place. Warner/RWS brass, RL50, CCI35, and 500gr Cutting Edge Lazers. I had 260 rounds on the barrel going into KO2M and 340 rounds when I traveled to Virginia for Poke the Bear in October and took the top spot there with the same load.
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There is nothing wrong with using ES as a constraint. In a standard normal distribution you can assume the relationship between SD and ES that you mention (depending on your CI). I usually see velocity curves that are fairly biased though and that makes SD a less useful number. For a shooter, eliminating the extremes is more important than anything else. SDs can be low while still having an odd extreme high or low. In a large enough sample size, they may not even be true outliers. ES really does make statistical sense for us.
Using "anomaly" in place of "outlier" seems pretty harmless since the intent is clear enough.
-Alex
Have you tried RWS?
As far as ES goes, I know the rifle you shot had an ES of 7 fps across a 15 round string the day before you shot it at KO2M and seemed to do really well for you. The reason I run ES and not SD numbers is to take any outliers out.
Having two rifles that I loaded for in the top 7 at KO2M felt awesome and I'm really glad I brought the Hellfire and had you shoot it.
When I got the loads working as well as I did with CCI there wasn't a point in trying anything different. I've got RWS to try but until I have issues with this lot of CCI I'm not changing anything.
Well I was honored to be a trigger monkey on a gun with a history like that
I'm converting one of my 50s to 460 and I must say, the performance of the hellfire gives me pause but that would be a ground up new gun. Kinda like the idea of bigger splashes but it seems like a lot of the guys that went to 460 are going back to 50 for one reason or another so I have some research to do.
In FCSA comp, most of us prefer the RWS primers and see more consistent velocities with them. That said, we are also typically loading to lower load densities than on a 416 and I wonder if that is why we are seeing a performance difference. Can't argue with results though. I know plenty of people that get tighter velocities with the 215 then a 215M too.
-Alex
Were you at Pitts Finals too in Nov. 2023? If so where did you finish?
No, my last match of 2023 was 1st place at Poke the Bear. Before that was 2nd at KO2M , 1st at Conquer the Castle. In 2022 had a stellar year 1st at Spearpoint July, 2nd at Conquer the Castle, 1st at Spearpoint August, 1st Spearpoint season Championship then 1st at King of 2 Miles.
To each their own, first rifle I went with was a Savage 110BA in 338LM with a Leupold Mark 4 8.5-25x50 with M5 turrets. Had alot of fun and was a solid rifle to learn on, ended up keeping it and upgraded the barrel after the original was shot out. We also did some minor stuff like changing to a timney trigger and glass bedding the rifle.
Next rifle I picked up was my dream 50bmg which is ok on accuracy (barely sub moa) but it wasn’t really intended for any kind of competitions and was just a fun gun id always wanted. Next real ELR I ended up buying was a Seekins havak in 300prc but it’s for hunting not competitions and was designed that way. Finally I settled on a custom 375CT built on a Lawton action that was a new rifle build, still working on getting set up for reloading but so far I only have one complaint but that’ll get fixed once I go to a faster twist to handle longer high bc bullets. For glass I ended up moving the Mark4 to the 50bmg and put NF atacr 5-25x56 on the 338LM and 375CT. My journey down the rabbit hole was aided by starting out shooting bench back in the mid 90s, what it takes to shoot 1k is so easy now and much cheaper.
Next rifle I picked up was my dream 50bmg which is ok on accuracy (barely sub moa) but it wasn’t really intended for any kind of competitions and was just a fun gun id always wanted. Next real ELR I ended up buying was a Seekins havak in 300prc but it’s for hunting not competitions and was designed that way. Finally I settled on a custom 375CT built on a Lawton action that was a new rifle build, still working on getting set up for reloading but so far I only have one complaint but that’ll get fixed once I go to a faster twist to handle longer high bc bullets. For glass I ended up moving the Mark4 to the 50bmg and put NF atacr 5-25x56 on the 338LM and 375CT. My journey down the rabbit hole was aided by starting out shooting bench back in the mid 90s, what it takes to shoot 1k is so easy now and much cheaper.
