Seating Depth Tested - Stop Chasing the Lands - It Works!
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- เผยแพร่เมื่อ 30 ก.ย. 2024
- In this video I demonstrate the process of tuning COAL from "Chasing the Lands is Stupid - Don't do it" video. We show the original 16 group results of testing COAL, confirm the results with more samples and expand the data set.
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I use spreadsheets a lot to analyze data. And I shoot.
Try this next time you're trying to find a node.
*Split your group sizes into two. And assign half a positive, and half a negative. Plot BOTH of those numbers along the X-axis again.*
7:40, the .248, make +0.124, -0.124
Plot the pos and neg individually, but overlay on the same chart.
Then, for an algorithm... derive the open area that the new chart creates.
Greatest open area will be the most 'settled' spot.
After I watched Erik Cortinas video I realized how foolish chasing lands was also. I mean he’s a pro for a reason, and his videos are changing up my reloading no doubt.
I like the idea of trying to tune a load you haven't had great success with
Proof's in the puddin'. Can't argue with data driven results. So much better the sweet spot is now mag length.
To be accurate: "The proof of the pudding is in the eating."
Just wanted to take a moment to thank you for this video. I've only been reloading for 2 months and I just recently found a good charge weight for my 7mm RM, 162 gr ELD-X that has produced an SD of 8.3 and ES of 35. Throughout my development, I was always .020" off the lands. Decided to give this video a try, and WOW!! Like your video, I worked in .003" steps, each time pushing the bullet a little deeper into the case since I was starting at .020" off the lands. I went from an unacceptable 1.366 ES MOA to a .601 ES MOA. As a very new reloader, I'm quite pleased with the improvement. Again, thank you for putting this together.
It's a good thing to mention that the reason why we shouldn't care about where the lands are in COAL tuning is because bullet seating depth can be used to tune the load volume of your powder and brass. A bullet seated further in the brass = less air and therefore less inconsistency in powder burning. Nosler and Hodgdon both state that loads near or over max volumes (compressed loads) generally yield greater accuracy. It also provides more consistency over temp change as any air inside the brass will change in pressure when temp changes.
I've used this method on 3 different rifles, 3 different calibers, 6 different bullets and powder. As long as you have consistency in your brass, neck tension, bullet BC, and powder... It works! I've been watching your channel, waiting for you to discover this method. You're very detail oriented and a smart dude, can't wait to see what I can learn from you.
Been doing his workup too... It works
Same here, I have a new .300 WinMag figured out in one box of 220 Hybrids following his method. I'll tweak it a little more, but I've never dialed in a rifle so fast. I used to buy all kinds of bullets and powders and try everything under the sun. Now I know better.
About to do a 10 shot test. I’m going to make those cartridges magazine length, instead of 0.02” off the lands, so I don’t have to single feed from now on. Great video.
Actually doing 4 today.. 2 powders and 2 bullets... At the range watching this... 😎🤠
22-250 and Berger Varmints with IMR 3031 and VIHT 540
I just totally geeked out on this 2x back to back awesome info I’d love to see this done in different cartridges, powders, and bullets!
Something ive figured out many of these loading and testing methods work absolutely when dealing with a match quality barrel
When using a factory barrel you can have verying results altho the fundamentals of the process are there
Example
Eric says the harmonic node is around 6 thousands spread in then out so 12 thousands
Over all and when loaded short you will be able to cruise through the 6 thousands node till you get to the back side of it then back your seating depth off 3 to 6 thousands again to arrive back in the node...
But with a factory barrel you may have a node every 6 thousands or every 10 thousands or 12 thousands and each node will have wildley different outcomes in group sizes...
then the length of the node could only be 2 to 4 thousands only giving you a couple hundred round window to go work with before migrating out of it...
So where i 100% agree with eric i sometimes wonder if it's actually worth it when talking about a factory button or harmmer forged barrels... eric himself has also said he had really only ever owned premium rifles.
i would love to see a series where he does load development on camera with the 6.5 needmore with a few different powders and projectiles start to finish to see if his experience matchs mine
i have a factory 223 tikka barrel and it shoots .7 to .9 regardless of what i put in it (within twist and still using premium lead) however i could never find a load that goldly locks a sub .5 moa
Now my .308 factory barrel is the opposite it LIKES what it likes and HATEs what it hates. im talking .3s or less for what it likes and 2.0 for what it dont like...
Whats your thoughts and could this be reasonably tested?
Im also talking with limited experience load developing
3 cartridges 2 factory barrels, 1 match, and 8 or 10 different load combinations between them.
you, JRB, Eric, Impact and reading the winds have been my biggest references
I really like this method and have been using it with good results. However I've been loading pretty hot loads for gasguns, both 556 and 308 which seem to be much more finicky on node size. One thing I think isn't discussed by Eric is the relationship between seat depth and combustion chamber for the powder. For example I may find a great ES SD node at a seat depth but the accuracy is bad. Tuning the seat depth down I get accuracy but now I'm compressing the charge and the crunching powder gives bad combustion. This it turns into a guessing game of chasing variables trying to anticipate which charge and depth is the sweet spot. Curious if you encounter this or if you have enough case capacity that this isn't an issue. Running high performance 556 seems like a game of finding a load that exactly fit 100 percent case capacity with the perfect seat depth.
IIRC Erik is using different cartridges from you, and he's using them in a custom bolt gun. I don't recall if he's single loading or feeding from a magazine, but either way, he might be able to seat OUT a lot further and find seating depth nodes which you are constrained from if (for example) you're trying to load long heavy bullets and keep them within AR action and magazine OAL limits. Remember, his technique isn't "chase the lands", it's "find out how far OUT you can seat without actually jamming the bullet into the rifling, then work back from there."
I agree Josh K that compressing the powder is most likely not going to be good. If I understand correctly , the pro-shooters stay away from compressed loads because of the inconsistency in accuracy it causes. I believe most hand-loaders would suggest using a different powder (to avoid compressing) that doesn’t fill the cases as much for the accuracy desired. Also as you probably know shorter bullets typically have a lower B.C. , but in some cases doesn’t make huge difference unless trying to defeat wind drift at extreme long distance ranges. As I heard it said many times before, bullet drop is consistent and predictable, however wind drift is not. So I suppose it’s really up to one to decide how far do they really need to shoot. For hunting many would argue any shot over 300 yards on larger game e.g. Dear, Elk is unethical. However for shooting paper & steel no limit need apply. Happy shooting
✌️😎👍
I’d say that sometimes it doesn’t work. My rifle has enough throat erosion to where the jam plus offset is further forward than where I already know I get pressure from with the BTHP (way into the lands). I’d guess that if you get that jam # when the lands are new and sharp, it’s probably a very different #. So for the average person, I’d say it’s still important to know where the lands are for safety. Now the ELDM with a different shape I can move forward. But I’m still careful. That jam # is still way forward of where I can even safely load that bullet.
I liked what Eric mentioned about starting with test loads at minimum C.O.A.L. and seating 3/1000's longer in each String (shooting in the same order). This way when you verify your node, all you have to do is seat the remaining loads to a shorter C.O.A.L, as opposed to using a bullet puller to correct the short rounds.
Now that’s sound advice!
Also, seating the bullet deeper means higher chamber pressure. So starting short and working up prevents any over-pressure while tuning COAL.
Worry more about what is under the bullet and what the bullet goes through to get to impact. Moving seating depth plays more into gas mixture case bullet relationship than how far your bullet is in lands. Just my 2cents. Jamming ain’t easy. 😅
My personal experience shows that chocolate chip cookies are best when hot and gooey.
YMMV, but it would be wrong .
Good stuff. I’m going to be working on this. I’ll rewatch and try to get started. Just starting into 6.5 Creedmoor.
What app did you use to measure group size?
I think you're darn right it was successful. It can be seen on the graph the nodes coming in & out in an almost sinusoidal form as predicted by many besides Cortina.
I wonder, would it be worth testing a substantially different charge weight at your new optimum ogive length, just to see if the rifle system seems to prefer that length regardless of charge weight?
Great stuff.
Regards.................Rotas.
Chasing lands is stupid for sure. I 100 % agree. If I am developing a load with a new bullet or for a new rifle, I will find jam, back off 10 thou, re check it to make sure I'm not still going to stick a bullet in the rifling, and then that is my starting measurement. My neighbor was a bench rest shooter and showed me this method many years ago. He was also the one who told me that full length sizing is the way to go.
I feel quite a bit dumber after watching/listening to this post!
Keep up the good work :/
Plus 1 LOL
It might take me a bit o time - these guys are soooo far ahead of my setup. But at least I am heading in the right direction.
Thank you for adding your own data to this. i am not a precision shooter but I believe the reason people have gotten so worked up over his method is that it is simple and easy to understand. I would love to see you test with a load that has not been shooting well. I would also wonder if it could be used with the COAL found in reloading manuals as a starting point. that way someone just starting reloading might have a way of tuning without having to measure jam.
I wish I could do all these tests right away without running out of the projectiles I use...out of stock everywhere, sigh. I'll have to stay with a lucky guess load for awhile.
If I may, lucky educated guess will work in times like these. There are a few sites that will offer an accuracy node without buying the book. Pay attention to bullet weight in relation to barrel twist.Build a binder with one manual and note pages. For instance, I dialed in an SST hunting load 2 months ago with a new powder and a hundred box at appropriate Temps. Three shot groups in 3 cold bore sessions yielded low s.d., adequate performance to 225 yards, and 23 in a box for the next 5 years. Bulk is a different story. Bulk stores around here restock Thursday night. Good luck.
as far as im concerned seating depth, jump gap, and "land chasing" ( or whatever YOU call it) are all the same thing, or at least yield the same result. just a matter of semantics, or ones train of thought.
I've watched and followed Erick Cortinas example and it works. Did it with a 223 and now fgtting 1/2 MOA groups reliably. I too used Lapua brass but went with 85.5g Berger LRHT bullets. You can also read more about tuning using bullet seating. on page 100 of the Berger Bullet reference book.
Very interesting, I'm going to have to give this method a try and see the results. I do have a load which so far has yielded a .43" inch group....let's see if that can improve out of my Ruger American Predator 6.5 CM.
When you change the OAL you change more than the length. Your velocity changes, your SD changes and of course the jump changes. You are not just changing one variable. The case volume of powder being compressed or not is also happening. What Eric Cortina says is you can get your rifle to shoot the load you have better by changing the bullet length. That is correct without a doubt. What he also says is it doesn't mean that your rifle won't shoot a different load better only that the load you are using will shoot it's best depending on the bullet depth. Using a Lee Collet Neck Sizing Die will give one as good a consistency in neck tension as using a mandrel to finish your case sizing. After all it has a mandrel. Everyone has their own technique of reloading but often people are chasing a ghost by over focusing on one thing and forgetting that other things are changing as they do the one thing, they are focused on like bullet length. There is always more going on than one looks at when reloading. But we need to keep it simple, so we have to find a technique that works for us. Eric Cortina has changed his techniques through time and passes on what he has learned. There is no perfect way to do reloading.
Good info here. Both Nosler and Hodgdon state that compressed loads generally give better accuracy and no doubt that's what the seating depth is tuning. It actually affects air volume in the brass and less air = more consistent powder burns and I don't believe Erik states that in his videos.
Slow down the dialogue particularly on the numbers - you're doing the oral equivalent of 3500fps. Hard listen despite the valuable info.
change the playback speed to 0.75..
I had to hit the pause button so I could let parts of it sink in. but yes a little slower when you are talking numbers would be appreciated.
I do a very similar analysis to essentially rule out the "bad" nodes then further dive into the areas with good nodes that feed reliably from the magazine... seems to work pretty well. Thanks for posting this thorough straight forward discussion.
It would be interesting once u find out what seating depth is best, then re test powder charges either side again to see if it makes any difference.
It definitely does! Found my sweet spots with the depth and then for my own testing went up in .3gr increments was pretty surprised with the results! Definitely need to find a sweet spot on charge and seating depth!
I don't think I am OCD enough to anneal my brass after every firing. I do want to shoot small groups and be able to hit metal targets out to about 600 yards. I do appreciate your videos, although I wish you could talk a little slower.
I went full ree on this process for my 300 win mag. I found jam at 3.735" with my neck tension on a 225 ELDm, started at 3.715" down in increments of .003 and then realized I wasted $200 worth of materials and my shooting is more inconsistent than any variable I'm changing lol
Great videos! New subscriber. I am curious as to know how you’re shooting groups? Is there a video on that? Vice, bags, etc...
Really great test. I wonder how the node works with seating pressure. And lubricity of the brass. Without having to go with such a light LBS of tension, if polishing the inside of the neck could be seen?
I'm working up initial loads for a .223-based wildcat and will be utilizing some of your (and Erik's) procedures. Question: Should I find a decent powder load first and then adjust COL from there? Two different powder (H335) weights worked really good on my last range trip, and I'm looking at developing one or the other.
Excellent work. I have but worked up a powder load. Now to do this seating test. At the shortest length, CBTO, how far off the lands did you end up?
Accuracy Node = velocity that the barrel resonates at. So, how does throat dia and length change from shooting alter velocity. Your Quest begins!
I would start with max mag length which would have put you at about 2.220 wich actually would have found that node much quicker. I get this is for data but most people still want to be able to load a mag
Smarter then the average marksman this guys is. I also refuse to to 26 dollars for targets. Not even 10 bucks for a damn piece a paper to poke holes in. I use paper plates and a sharpie lol.
I would run with the shorter bto lengths, not only were the groups good, but they also have a similar point of impact. I don’t think a person can just look at the group size alone, I think the point of impact come into it as well. Looking at the groups from your first video the point of impact is also shifting. Ad tune changes with barrel wear your zero will be shifting with some of those small groups. The shorter bto from this video held a more consistent poi as well, which will help keep your load in tune with barrel wear.
Actually, winter tires should be used as soon as temperatures go below 7°C and not just when there’s snow.
This seems like an excellent process in large part because it is data- and evidence-driven. By "exploring" further parameters which had not initially been in your test population, you are determining empirically whether or not your previously-known best node is merely a local minimum. Well done!
There are so many variables like which primer works better then which powder works better then which style of bullet ie boat-tail flat base solid copper soft point hollow points then crimp no crimp which is more consistent then the powder load then the barrel length the twist rate and that’s per each gun
I really appreciate this video, and would love to see more like them!
good video, but it could have been so much more. you made a good group, better no doubt. but i believe most are looking to work up a load and make a mediocre group good.
B
I found this video very interesting. I am curious about seeing if a not so good load can be adjusted to a point of working well. Would like to see if tinkering with some bullets/loads I think wont work well with my rifles could actually work good.
I am sure we are going to get there. Not sure what order, but I think that this is an interesting topic to cover.
All I look for in my handloads, since I am not a competitive shooter is reasonable accuracy out to about 500 yards, since I doubt I would ever take a shot at an animal beyond that. At that distance, I would take 4" group all day long; which is about the average in the huge variety of calibers I shoot. I know from experience with the components I use, that they will have the ft lbs of knock down power to quickly and humanely take the game I hunt. All of that other information is good, but it doesn't take all of that for me to keep more venison in my freezer than I can eat.
I am of the same mind. I am here because i can't consistently do 4in groups at 500 yards. So I want to make better rounds. These folks have got it down and are sharing great data and processes. What a great time to be a reloader.
Why do you test at 100 yards. Go out to 200 or 300 yrs so we can see what is really happening.
Great point Jerry! I've asked the same question on other sites reviewing cartridge load development...but no one wants to validate their test at longer ranges. Guess their afraid of what they might find...hummm! I zero at 100yds, document a three shot group at 100 then validate at 300yds. A nickle size group at 300yds (7mmWSM) gives me a 1/2 to 3/4 MOA at 1000yds...no wind.
Unfortunately its difficult for some people to find more than 100 to 150 without a very long drive.
@@BoltActionReloading Thanks for the awesome video and reply! That's a good point but certainly worth the effort if a longer range is available. I'm an hour away from my local range and don't shoot as much as I would like for that reason.
Its not easy for me to get anywhere, when I actually have time. I used to do everything at 150 since that is the furthest distance I have that I can access when I want. All the comments were "why aren't you at 100" no one is ever happy. You need to verify your loads at further distances but keeping the audience happy is not possible. If I had the opportunity I would test further more often, but its not going to keep me off my range.
@@BoltActionReloading Roger that, Just keep doing what your doing...we appreciate it tremendously!!
I'd love to see an experiment changing the seating depth of factory ammo just to see if it "blows my mind" like Erik says in his video. If you can improve on accuracy on mass loaded ammo with a bigger range of quality control, tightly monitored hand loads should be a no-brainer.
Chad I did this for my .222 and my .270 hunting rifles a lot of measuring on handloads against different factory ammo as long as you start with projectiles that seat out far enough to reseat it works got the advice from an old gunsmith I knew. Sorry no video to prove my claim but try it.
Interesting suggestion on factory ammo. Since reloading components are a problem. I would like to see a testing video on using factory ammo. Lengthing or shorting seating depth to tune a load
What app. Did you use to on the group size?
Basic data science in any discipline requires statistical analysis to validate any result from the null hypothesis that there is actually no difference between your individual group size tests. I SEE NO valid analysis here that would indicate that your squiggly line connecting your data is anything more than systemic noise, particularly going from high and low and back. If you want to prove to me that there are actual real differences in those loading vs seating depths, I'd need to see multiple independent groups for each and typical statistics applied. I'd want to see a P value of less than 0.05 giving a 95% probability that any two values are indeed different. You can run a basic ANOVA analysis for overall experiment and can also cheat looking at individual point groupings A' vs B' type T-tests. Now that I've looked at a variety of different load and 'tuner brake' videos I am convinced that for most of these, ya'll are fooling yourselves into thinking you are actually doing anything real. At least you can't prove to me or any scientist of the valididy of our assertions until you show some valid statistics. SD means absolutely nothing unless to perform comparisons between multiple SD's at the same variable space.
Feel free to post statistically valid sample sizes on your channel with a full analysis. I'd love to see them... because I don't see any sample sizes on your channel. Oh, and you absolutely don't need all of that to "prove it to any scientists". 99.99% of "scientists" today will believe anything they are told to believe, regardless of evidence, because that same percentage have terminal hypogonadism. This includes the idiots that taught my grad school classes and those that I now work with. Both of which thought they were hot shit because they had letters before and after their names, despite the fact that they were dumber than a sack of rocks. Contrary to what the public believes, "doctor" doesn't mean smart. It means you paid a lot of money and did a lot of work for a fancy piece of paper. Mine is in a box somewhere or something I think. None of that matters anyway, because science and medicine as professions are both deader than door nails due to the hypogonadism.
Super interesting. Looks like if I’m going to keep chasing for smaller groups, annealing is going to be a must. Can’t bring myself to shell out the $1300 just yet though. Someday...
get an annalease 230 and done,that'll give you money for a bore scope,if you can't see it or measure it you don't know, boretec it was around 150 or so,
Do the anneal with a bezel torch and drill. Bit slower but a cheap way to get it done.
What APP or software program do you use for calculating group size and related data?
OnTarget PC
I deleted my initial comments about the 3 shot group thing, I did a very piss poor job of explaining myself... That is to say I made no attempt to explain myself. At any rate, I'm a *huge* fan of your channel and of Eric Cortana as well, so please don't interpret anything I said as a criticism of either you or him.
What software did you use to make that graph?
Great info thanks for the video keep up the good work.
Can full length resizing using the expander mandrel from 21st century take the place of using a bushing?
yes
Excellent info! I’m anxious to give this a try!
I resize the same way, although i use a APW expanding die set, and im still building an annealer 😂
@D J i use a butane torch and a lee case holder Chuck up in an impact driver
@D J yes i only keep thr flame on the neck for 8 seconds
lol, the tire example was stupid, of course you change your tires if it promises snow. Don't follow his idea about tires if you live in Norway LOL.
Eric Cortina has a plethora of thousandths, no?
To shoot to 100yards is not a trustful issue. The wobbling of the cartridge getting larger after that, than it will settle. To shoot decent groups on longer ranges shows the real long range punctuality. This 100y test will drive you all a faulty conclusions. You have to choose a non windy day, or closed range and test it for longer ranges 300, 500m.
at 10:36 should the top line be CBTO? i assume this is just a typo
I'm new to reloading and I'm learning at lot from you. My first question (of the thousands to follow) has to do with how you manage shooting all these test groups and cleaning your barrel. I run 5-7 shots then I clean. I've been told to shoot (and record) until the groups open up...then I'll know how my gun handles a fouled barrel. What are your thoughts? Anyone?
Hi John, It depends what "game" you are trying to compete in. The BR guys tend to clean endlessly, some PRS guys swear by barely cleaning. I try and clean between range trips (for me 150- 200 rounds) few people like to publish their process because in the internets eyes no one is right. Good Luck. Generally speaking should you clean? Yes. How frequently? If you loose accuracy, clean. I would not advocate for leaving a barrel dirty for long durations of time. Hope this helps in some way.
BAR
@@BoltActionReloading I have never gotten a response from anyone before. It REALLY means a lot. Thank you!
Good stuff. However I think to talk COAL is totally subjective. The only objective measurement is CBTO. When you talk COAL, you must define the bullet style. My 2Cents.
Great video and lots of good data. Thank you for that, but I'm confused about one aspect. You mention that the CBTO measurement for "touching the lands" in that barrel at that time was at 2.222", and the jam length you chose to use as your baseline was 2.270". From there, based on Erik's procedure and recommendations, you started your testing with a CBTO of 2.250". Aren't you effectively .028 "into the lands" at that length? I had assumed that Erik's procedure of using .020" off the jam would result in a short jump, but maybe not? Even the node you found at 2.229" is a bit "into the lands". It seems to me that you found a great node at 2.205" which, theoretically, is about .017 off the lands, which makes sense to my mind. Did you end up staying around that CBTO node (2.205")... until it moved? Thanks again.
Interesting, I tried this on my 6.5CM Defiance/Bartlein barrel with 140gr ELD and did not have the same results. .010-.014 off the lands performed the best and got progressively worse the further off the lands.
I would love to see a comparison of load tuning.
What has the biggest effect on the group size.
Neck tension or seating depth.
What is the first step after finding a good low sd load.
Good video. Your testing and data expands nicely on the base coverage of this topic by Mr. Cortina. One thing i found peculiar tho, was what you said near the end of the vid; where you said "i can't ignore the groups down at that shorter end either tho...", but you'd want to get more data there; "...need to repeat a larger sample group..." I found that a very odd comment, because it seems to me that accuracy node b/w BCTO length of 2.205 to 2.199 was significantly superior to the one b/w 2.232 and 2.226.
Great video - bit confused with the graphic at 10:34. Said next text coal 2.203 and coal 2.204 = coal 2.824. Did you mean CBTO?
I watched Mr. Cortinas video and figured from his success he was correct. Proved it by witnessing a factory rifle do 1/2 MOA and under groups with a factory Hornady varmint load.
Neck tension is the amount of pressure to move the bullet when seated. Calling it .002" really makes no since but I understand where you are coming from. You should have started at .01 or .005. You will find a much better node. Erik is scared of pressure hes going by sinclairs mentality (reloaders tooling is inconsistent). Not mine. this isnt always a concern. Check quickload to make sure you are safe if measurements do shift.
Something else to maybe add. The reason you do not do not do not try to stick with a vibration lull that’s very sharp is because just 15-20 degrees of temp change is enough to put your FPS far enough out of that timed lull you open way way up. And therefore the rifle can only shoot good at that exact temp only. Which is why it’s best to stick with the very middle of a at least .01 wide group. Even stretch that group .001-002 one way or the other to really narrow the middle. The bullet speed can change but the vibration speed does not. Or at least far far less. Based on temp. Stick to the middle of your largest lull unless you shoot indoors... in a temperature and humidity controlled environment lol. Think of it that way. Timing.
“In a rifled bore in front of the chamber, the short rear section is without rifling, and allows the bullet an initial "run-up" to build up momentum before encountering riflings during shooting. The most posterior part of this unrifled section is called a freebore, and is usually cylindrical. The portion of the semi-rifled bore immediately in front of the freebore, called the leade, starts to taper slightly as it becomes the rifled bore and guides the bullet towards the area where the riflingless bore transitions into the fully rifled bore. Together the freebore and leade form the throat region, where the riflings impactfully "bite" into the moving bullet during shooting.” -Wiki
Rifles differ greatly in Freebore length and Leade Taper angle and length. That’s why there’s so much to improve upon over universal retail ammunition. Take the mystic away by measuring and knowing your rifle barrel’s throat region lengths and angles.
Barrels vibrate. Firing pin. Not just hitting but stopping, two separate thing. Primer. Especially cause it’s the sharpest vibration (why smaller primers work better...) and charge the biggest but not the only and certainly the slowest. All 3 go from front to back millions of times per second. And not at the same speed or intensity. Seating depth is just like fine tuning a powder charge to accurately time the bullet leaving the barrel when the most amount of these vibrations is towards the rear and the front is the stablest. Find a coinciding lull in front vibrationS and you’ll find one hole. You can time that exit using any seating depth or any powder charge by moving/adjusting one or the other. But moving the bullet is just more accurate.
Hi bolt action,love you videos. Are you on FB/insta able to DM ? I would like to pls know, when finding good node , what seating depth do you use ,as per your following vid you the play with that ,but for the node finding, do you just use factory std length, as I understand you looking at the data not the groups yet?? Thanks very much and for the awesome channel
after watching his vid i tried it, all my brass was condition the same,lapua 3 firings,fl resized .002 bump on the neck , anneled ,for 308 (tikka t3 lite) I used an m30 die for mandrill gives me .002 neck tension.using hornady custom grade seater (no exander)and sizer with a mic adjuster on top.I bought a new co ax press after seeing my run out from the rc.i ordered the bore scope but didn't get until after the test.i'm using 178eldx over 43 gr varget,the case is 100% full with a little crunch just settling not compressed.and cci br2 primers seated using rcbs bench mount.starting at mag length i went back .003 i did like 8 sets of 3rnds.i found one at the last set, so i loaded 5 the next day the bore scope came so i cleaned it until no copper,they shot 1moa same as the rest, I wasn't sure i can go back more I didn't get any presure signs but i would be compressing .I stopped as i only have around 50 left and can't find more. i'm thinking either better dyes and mandrills, switch to 175 match king (wanted this for hunting load as well as to start distance) or leave some copper on the lands for a seasoning,open for ideas, thank you.
Always test loads between 0.060" and 0.080" off the lands and possibly more. A lot of bullets will just simply shoot better with a bit of jump.
Good review of your process. After you identify the seating depth node you want to use, do you ever go back and sample powder charges in the same vicinity to fine tune the load? I am guessing not but don’t know if you *always* determine powder charge first.
If you reference your seating depth to jam, how is that different than referencing it to touch? I know the differences in what they are and how they are measured. My point is that both will change with barrel wear. Once you find your depth referencing jam, do you plan on not changing it until you see a change in accuracy? What happens if you go preloaded to a match and you see a change during the match? I think that the real question is whether the most important issue is bullet distance to crown, or jump to lands... or a combination. If it is solely distance to crown then barrel wear can be ignored, but I do not believe that is what Erik was saying. For me the real question should be is there anything wrong with retesting for jam or touch and loading for your next match on that basis? It seems that this could only be determined by over the life of a barrel testing.
I wonder if you have plotted the angular location of each test group, as well as its size? The barrel movement is not, of course, limited to a 'straight line vibration', but is likely to have a rotational component, as well...just thinking. Sorry, but I did not 'get' whether you had looked at actual velocity of each round, or at each node, to see if there is any correlation of velocity with COAL?
Great description on zero length.
After I do this I then adjust the zero of my powder charge.
Well done.
Very well done, little fast on speaking lol. Take same tests to try bullets you previously weren't impressed with. Thanks for sharing
What if jam -.02 end up being .02 longer than max cartridge length.
I wonder about taking a load with the same CBTO And shoot it at 300 yards at well as at varying outside temperatures and barrel temperatures. I'm trying this process and have 2 lengths ready to test with 10 shot groups. My 3 shot groups are the smallest I've shot at this velocity. It has helped having a micrometer seating die.
I’ve come to the same results in my rifle with the 140 eldm.... they like to be jumped significantly
If like to see you try it in a loading that had good or better velocities or SDs but not group sizes just to see if revisiting that would be a good test
My jam per cortina is way to long to fit through my p-mag. I hope i can find a node that will fit through my mag. If thats the case it defeats the bullet jump theory just like yours that were at the shorter side to fit your p-mag.
I have a video request - would you consider testing to determine if velocity test and seating depth test results are impacted by using new brass vs brass that has been fire-formed?
i want to know if changing seating depth is measuring the effect of jump, or the effect of the pressure in the case (more depth = more compact volume, does that create higher or lower pressure)?
Working on it now also in my 6.5 CM Tikka I just did the 10 shot powder charge over my MS and now I will start with seating depth.
I guess it would depend on the speed you are looking for
Just look at the dimensions almost and you could see the sweat spot
Just a thought but I'm a amateur
Custom is always tough because everything is way tighter
I haven’t started load developing with bullet seating other than making sure I am not Jammed. Consequently, anytime you are at 1/2 MOA you are shooting very well. It seems like the 6.5 likes to jump
If you are not wanting to cut holes, just seat the bullet to the depth of a brand new box of store bought ammo and work the loads to possibly tighten the group.
I shoot a ladder test for seating depth 2thou apart.
Recording where each shot landed so you can see where they tighten up. Saves on ammo and tells you the same thing.
I'm planning on running load development for three calibers this year. I had planned on utlizing the Saterlee 10 load ladders test and then apply Erik's process to fine tune.
Thanks for the video series and splitting that Erik's process works.
Per your request in video, I would like to see you revisit the Nosler RDF 140gr. In 6.5 Creedmoor..
Maybe you could do some ladder testing with several powders and then fine tuning with Erik's process. Essentially doing load development from the ground up.
Working on the powder node at .020 off the lands. The last fired rounds, had three that tightened up and my next test will be in between those test loads. When I find the powder node I will use this method for adjusting to the lands.
Liked and Subscribed even though I barely understood anything! JK, i can learn a lot here, and it is great how you are working off some of Erik's work. For some reason, hearing it again, explained slightly differently, is helpful. Thanks for sharing!
this was perfect.
I wouldn't waste any time testing oal's that don't fit in the mag... unless the shooting application involves not using the mag at all.