“Your groups are too small” vs barrel life

[blksno]

If it won't shoot sub moa with 2 shots.....3 ain't gonna make it better.

When I'm starting out with INITIAL load work...this is my starting point. 2 shot groups to get an idea of pressure, powder charge and group size.
If I'm working up a series, and none in the series show promise with 2 shots...I don't need to re-test with 3 shots. I need to change a variable.
If pressure is good, and speed is good...I'll change seating depth or crimp (adjust neck tension) and re-test with 2 shots toward the upper end of the velocity goal.

 

[nealm66]

This is similar to what I do. I rarely crimp though. Only sometimes on bullets that have a groove. I've had that help es/ds but never accuracy? Interesting

 

[VenatusDominus]

What I find telling from Keith Glasscock's video is that his highly specialized/customized F-class rifle is not the 0.175 MOA shooter you would assign from his 3 shot group, but is actually a 0.761 MOA shooter based on his 33 shots of that load. That should tell us something about our hunting rigs and our over estimation of their true accuracy.

 

[RegionRat]

It is amazing what a good F-Class shooter can do at 1000 yards. In a three relay match, that means sixty record shots and many times they pull pit duty or have to score between their next relay, so no time for cleaning or playing or fussing with seating bullets in between. So it represents pre loaded ammo. Here was a card shot in a match up in Alaska that was shared on the FB page the other day. It is an exceptional example.

600-42X means he was inside the X ring 70% of the shots. Some beautiful shooting to say the least, and shows what is possible when the planets are aligned.

Now it would be interesting to hear what John says the load/barrel will do on the next match, or if it falls completely out of tune.

ETA: folks have asked what the target dimensions are for F-Class at 1000 yards, for example the 10 ring is basically 10" and the X-ring is 5"

 

[Doom2]

That took less time than I thought it would! The internet has made it sound like the only good rifles are .25 moa. I get sick of hearing how "My 6.5lb all in hunting rifle shoots .5 moa all day at 1000y". If this was true, these rifles would be winning 1000y bench rest competitions against 20lb rifles. It simply isn't true. A true 1 moa hunting rifle should never be gotten rid of. I think the really good, I mean really good, hunting rifles that are .5 moa, still pitch one out to 1moa here and there. "Called shot. That was me, not my rifle."

In my small statistical load development and long range validation, I want to see solid sub moa accuracy. I totally agree with the Hornady guys that loading in .2gr increments is statistically inconsequential. Unless shooting something like a 17 Hornet I rarely make powder adjustments less than one grain. The smallest that I ever make is .5gr. When I load develop I shoot one shot 1gr increments all fired at the same dot. If the rifle likes what we are using it will usually show pretty close to an moa target, even though we may have increased 200fps to 300fps in the ladder. If the group in the ladder is all over the place, I switch to a different powder. I have seen changing primers take a rifle from 2.5 moa to .5 moa. Wouldn't think it possible had I not seen it. Still too small a statistical sample to prove but it held up at long range.

I think if guys actually listen to the Hornady podcast, they could save the amount of powder, primers, and bullets they shoot to develop a load, in a third. They aren't telling you need to shoot hundreds and hundreds of shots to develop a load. They are telling you not to do that, because unless you do, the small changes that you are making are statistically unproven and likely will not change anything. It might make you more confident, which is priceless.

I could sell a lot more bullets if I told guys to load in .5gr increments in 5 shot groups in a ladder up to pressure. Then take the best group and work up and down from there in .2gr increments to find the best group. Then take that best group and work the seating depth in 2 thou increments in 5 shot groups to find the best group. If a guy has done this he has gone through hundreds of bullets and they are all statistically inconsequential. When you are making these minute changes you would have to shoot 30-50 shots at each change to prove it to be actually better. They are saying that if you actually shot 30-50 shots at each minute change it would prove to be not different.

The guys that take offense to the Hornady guys are the guys that take hundreds of shots to develop a load. Now Hornady comes along and tells them that they have been wasting their time and money and it offends them.

My method to load develop usually takes less than 20 shots, including zeroing and confirming drops. Sometimes we get that rifle that is picky and we have to try several powders to find what it likes. There have been a few that have taken us 70 shots to find the combo but I never tinker a rifle into a good load.

I'm not a hunter but shoot and reload. I come here out of interest and to pick up knowledge so when I encounter hunters during my RSO duties I'm not left in the dark.

I was writing an epistle but when I saw this post it went the delete route. Your take is exactly what I took from a number of their podcast. Nowhere did they recommend 30 shot groups. One thing I think the Hornady guys could do is show more of their data and also show how to analyze their test data.

Someone also brought in Keith Glasscock of Winning in the Wind. He is an accomplished shooter and does an excellent job of explaining things including issues related to reloading. There is also a series on statistics on The Precision Rifle Blog that everyone, especially those who use chronographs, should read.

How To Predict The Future – Statistics For Shooters Part 1

I actually believe the average shooter might get more value from this Statistics for Shooters serie...

precisionrifleblog.com

 

[Huntnful]

I'm not a hunter but shoot and reload. I come here out of interest and to pick up knowledge so when I encounter hunters during my RSO duties I'm not left in the dark.

I was writing an epistle but when I saw this post it went the delete route. Your take is exactly what I took from a number of their podcast. Nowhere did they recommend 30 shot groups. One thing I think the Hornady guys could do is show more of their data and also show how to analyze their test data.

Someone also brought in Keith Glasscock of Winning in the Wind. He is an accomplished shooter and does an excellent job of explaining things including issues related to reloading. There is also a series on statistics on The Precision Rifle Blog that everyone, especially those who use chronographs, should read.

How To Predict The Future – Statistics For Shooters Part 1

I actually believe the average shooter might get more value from this Statistics for Shooters serie...

precisionrifleblog.com

Good read for sure!

 

[bluedog69]

It is amazing what a good F-Class shooter can do at 1000 yards. In a three relay match, that means sixty record shots and many times they pull pit duty or have to score between their next relay, so no time for cleaning or playing or fussing with seating bullets in between. So it represents pre loaded ammo. Here was a card shot in a match up in Alaska that was shared on the FB page the other day. It is an exceptional example.

600-42X means he was inside the X ring 70% of the shots. Some beautiful shooting to say the least, and shows what is possible when the planets are aligned.

Now it would be interesting to hear what John says the load/barrel will do on the next match, or if it falls completely out of tune.

View attachment 606393

ETA: folks have asked what the target dimensions are for F-Class at 1000 yards, for example the 10 ring is basically 10" and the X-ring is 5"

Well under MOA at 1000 yds. Be interesting to see what he thinks the same number of shots would be at 100 yards. Under .3 MOA?

 

[matt_3479]

If you look at the standards to top level accuracy it's benchrest shooters and f-class. Majority of these guys who shoot 1000 yard f-class and 600 or 1000 yard benchrest shoot 3-5 round groups. There is just no need to shoot 20, 30, 50 round groups for everything it's just outrageous.

I don't mind the concept of once a load is developed to shoot 12-15 rounds for prs to see how your load holds up as your barrel heats up (big round count for a stage)

 

[VenatusDominus]

If you look at the standards to top level accuracy it's benchrest shooters and f-class. Majority of these guys who shoot 1000 yard f-class and 600 or 1000 yard benchrest shoot 3-5 round groups. There is just no need to shoot 20, 30, 50 round groups for everything it's just outrageous.

I don't mind the concept of once a load is developed to shoot 12-15 rounds for prs to see how your load holds up as your barrel heats up (big round count for a stage)

That is outrageous, which is why no one is recommending you shooting 30 round groups. The recommendation is to shoot groups appropriate for your rifle and application, ie. for a hunting rifle shoot 3 round groups or even better, 1 round cold-bore groups. Over the course of a few trips to the range, collect enough of these small groups to have 30 total shots. Measure the point of impact relative to the point of aim for each shot (x and y coordinates) and then plot them on a single graph. From this you can measure/calculate your true total group size, true center of the group relative to your point of aim, mean radius and probability percentages to hit within a given diameter (standard deviation). I may be wrong, but all the F-class shooters I know shoot three 20 round matches when they compete, I am not sure about the bench rest guys.

 

[RegionRat]

I don't know if there has ever been much of a wide survey done on the folks who take the podiums of F-Class with respect to their load development methods. Although much of the rest of the PRS details do get covered well by a web blogger named Precision Rifle Blog, aka: Cal Zant.

What doesn't really come across is in load development discussions is the context and terminology with respect to the number of small sample shots for screening purposes, versus the ones used for reliability.

So, not to argue but it isn't really accurate to say they only shoot a few shots in load testing. The folks I know personally shoot a ton of shots to have the confidence it will perform in a match setting or travel setting.

We may say folks don't shoot many for "screening tests", but if their rifle patterns and recipe patterns have been locked for barrel after barrel, doesn't the round count really rest upon a mountain of data? In a way, if they only shoot a few for verification, that isn't really load development is it? That sounds more like making sure the current barrel or components are the same as the last ones, not really load development.

In a professional setting, these guys do shoot 20 - 30 or more at a time to make sure they have things truly working, and also that many to make sure that their no-wind zero is solid. They don't trail blaze when it matters as a general rule. They also don't fool around with small batches that force more verification testing.

I know that isn't what casual folks want to hear, but the guys who can shoot the most are usually the ones with the better percentages. When there is a walk-on prodigy that wins, they have usually been given their pattern and recipe by the senior shooters, so their round count really includes everything their mentors handed them.

Their context isn't the same as a carry weight hunting rifle, but if there was a takeaway for the rookies, it would be to stick to the paved paths and use the best stuff you can find. Experimenting with uncommon barrels, chamberings, components, etc., and you can expect to need a lot more shooting for reliability in performance.

I'll splice in a link if it helps. https://precisionrifleblog.com/2023/11/10/a-2-time-prs-champ-reloading-setup-process-austin-orgain/

No real dog in the fight here, but I think there are way too many context, terminology, and definition shifts on gun forums when it comes to load development questions. The web is now getting full of videos where some channel host tests volunteer shooters for the precision and accuracy claims/skills. The results look pretty bad on average, with only an occasional good performance. YMMV

 

[cajun]

seems like in a lot of threads this topic comes up. I watched a video with Erik Cortina( 1000 yd f class) and Alex Wheeler ( 1000 yd bench rest). They basically said if they tested every little change with 30 shots they would shoot out the barrel. They indicated they knew from experience what they were seeing on target at 600-1000 yds in testing and could make educated decisions on what was working. These guys are world class shooters of course.

 

[ObiJohn]

If you have a 1 moa rifle and shoot a 10 shot group, how many shots are at 1 moa? How many are at .5 moa? What are the odds of the hunting rifle shooting the 1st shot at .5 moa? Asking for a friend....

I think it's safe to assume that the distribution around the center of the group with 20 shots will be Gaussian (most of the bullets will hit within half of the diameter of the group of the center, the rest will be in the outer half). In my experience this is invariably how rifles shoot. There's not a random distribution of shots within the diameter of the group (given enough shots), but a concentration towards the center of the group. Which means, in terms of the question, that it's more likely but not guaranteed to put the first shot within .5 MOA of the center than not. How much more likely? Somewhere between 50% and 66% based on statistics and the actual shape of the distribution (there's a coefficient) would be a safe bet. At 300 yards or less, it wouldn't matter. Beyond that, it starts to matter.

I will also state that my experience is anecdotal, and I haven't run enough groups to come up with any statistical data. I think one would have to do this with many guns. I wonder if rifle stability (some combination of barrel diameter and rifle weight) has an effect... if heavier rifles with heavier barrels distribute bullets in a Gaussian manner while light rifles with thin barrels may seem more like a random distribution to to more variance in barrel vibration and rifle movement. My Gaussian distribution assumption is supported by my experience with lower-recoiling rifles.

 

[VenatusDominus]

seems like in a lot of threads this topic comes up. I watched a video with Erik Cortina( 1000 yd f class) and Alex Wheeler ( 1000 yd bench rest). They basically said if they tested every little change with 30 shots they would shoot out the barrel. They indicated they knew from experience what they were seeing on target at 600-1000 yds in testing and could make educated decisions on what was working. These guys are world class shooters of course.

This would agree with the data that Hornady and Keith Glasscock presented. That is, tuning changes in seating depth and charge weight have no statistically relevant effect on group size/mean radius. If a load doesn't shoot to your goals in the first few rounds, you are better off changing powder or bullet (statistically significant effect on group size) than tinkering with seating depth and charge weight (statistically insignificant effect on group size). The one caveat the Hornady guys point out is that as velocity/charge weight increases for a given load, the group size open up slightly.

 

[RegionRat]

By shear coincidence today, a friend just made a table of some of the records and added some of the other details. More updates as they develop.