Seating depth - does it even matter?

[207North]

Heres best example i have readily available. I didnt shoot this i just guided a customer on his load work.

In my opinion, this tells me pretty much nothing other than its a solid 3/4” ish shooting rifle, ammo and shooter combo.

 

[solarshooter]

Heres best example i have readily available. I didnt shoot this i just guided a customer on his load work.

This is 3 different seating depths by what? Powder charge? Can you elaborate on what if any pattern you're seeing here?

 

[barehandlineman]

In my opinion, this tells me pretty much nothing other than its a solid 3/4” ish shooting rifle, ammo and shooter combo.

Well that tells me you dont know what your looking at. Only one group looks to be over a .5. Which could been him could be many things. But going off other seating depths of that charge its near pressure.

This is 3 different seating depths by what? Powder charge? Can you elaborate on what if any pattern you're seeing here?

4 charge weights 3 seating depths accross each
So 12 shots of each charge weight and 12 of each depth. You can watch a pattern and narrow down a node. This is just initial test, virgin barrel, virgin brass. Narrows down where to start once barrel has sped up, brass if formed. Should note customer was using alpha brass. His second outing with once fired everything here turned to 3/4-1moa accross the board. Back to virgin with the best load he repeated same groups. He didnt have annealer so he switched to peterson. Guns shooting consistently now. In any load devolpment you can have a group shoot really good and everything around it be junk. This is where the next day itll change. Finding a powder node and seating node combination is how you get a gun to repeat. Theres been 100’s of times where i had to re shoot a group because i pulled a shot ect. And dont get me wrong theres definitely situations where a group opens up. But theres typically a reason for it. Carbon, copper fouling, lot change, pretty sure @huntnful got to experience this with eldm. Thats why when i build me a new barrel i have enough material of same lot# to last that barrel.

 

[Nine Banger]

The arguments for nodes in this thread revolve around the observer being correct about what data is infallible and what data is a "pulled shot" or a "flier" and a decision is made to reshoot a group or not use the data.

You just referred to 100's of times you didn't like what you saw so you shot until you liked what you saw.

I could see these viewpoints being useful if we were talking about a barrel test fixture but these are field rifles we're talking about.

 

[barehandlineman]

No i said 100’s of times where i pulled a shot because i knew i did. And re shot it to verify. Not that 100’s of times i didnt like a outcome and kept shooting it until i got what i wanted.

 

[Formidilosus]

No i said 100’s of times where i pulled a shot because i knew i did. And re shot it to verify. Not that 100’s of times i didnt like a outcome and kept shooting it until i got what i wanted.

That’s exactly what you do when you reshoot “because you pulled one”= you remove the shots you don’t like.

I just find it ironic that your “personal gun hasnt shot over a .1 out past 1300y since i completed my load work”, but somehow you can’t help having a seizure behind the rifle and “hundreds of times pulling a shot”. So you are so awesome that you can definitively see- without question; real, factual changes in group size with .006 seating depth changes- but you can’t not flinch….

Ok.

 

[solarshooter]

Well that tells me you dont know what your looking at.

I really don't see it either man.

You can watch a pattern and narrow down a node.

I don't see any pattern. Just a bunch of small groups that are all pretty similar. If I overlaid these I bet they'd all look even more similar...

In any load devolpment you can have a group shoot really good and everything around it be junk. This is where the next day itll change. Finding a powder node and seating node combination is how you get a gun to repeat. Theres been 100’s of times where i had to re shoot a group because i pulled a shot ect. And dont get me wrong theres definitely situations where a group opens up. But theres typically a reason for it. Carbon, copper fouling, lot change, pretty sure @huntnful got to experience this with eldm. Thats why when i build me a new barrel i have enough material of same lot# to last that barrel.

Or, if you keep shooting 3 shot groups you will get good ones or bad ones, and the small tweaks you make may or may not coincide with those good or bad groups. And your pulled shots and myriad other gremlins you name are the classic way of explaining all the >0.1moa groups that come from a supposed 0.1moa gun.

 

[207North]

Statistically a .5” 3 shot groups can be expected to turn into a .9-1.15” 10 shot group and a 1.25-1.6” 20 shot group.

If you overlay these groups, with some hitting low and some off in windage. It looks like a solid 3/4” gun.

 

[JGRaider]

Backtracking.......not a good look.

 

[barehandlineman]

Backtracking.......not a good look.

Whos back tracking?

 

[mlevimadden]

Considering the world record bench rest 5 shot group at 1000 yds is 1.47", I would be extremely skeptical of anyone claiming their hunting rifle shoots sub 1.3" at 1300 yards every time.

 

[Pharmseller]

Considering the world record bench rest 5 shot group at 1000 yds is 1.47", I would be extremely skeptical of anyone claiming their hunting rifle shoots sub 1.3" at 1300 yards every time.

60% of the time, it’s sub 1.3” every time.

 

[barehandlineman]

Nobody said 5 shot atleast i didnt. Also world record 10 shot is 2.6 inches

 

[207North]

60% of the time, it’s sub 1.3” every time.

I can hit a bottle of sex panther cold bore at 2400 yards. 60% of the time. Every time

 

[mlevimadden]

60% of the time, it’s sub 1.3” every time.

I mean I'm used to the old standby "1/4 MOA all day....as long as I do my part". But "0.1 MOA all day at 1300 yards...as long as the environmental conditions are good" is a new level even for bold internet claims.

 

[207North]

Reminds me of…

 

[mlevimadden]

Nobody said 5 shot atleast i didnt. Also world record 10 shot is 2.6 inches

I know but I was trying to use benchrest as an example to show how outlandish your claim was and they don't track 3-shot records.

If we take the 1.47" 5-shot group record at 1000 yards, and reduce by 25% (the normal statistical increase from 3 to 5 shot groups), his 3 shot group at 1000 would have been 1.10". Now multiply by 1.3 to go from 1000 yards to your 1300 yard claim and we have a world record 3-shot, 1300 yard group, of 1.43".

I've never met you or shot with you, so maybe you can consistently beat the benchrest world record every time you shoot at 1300 yards in ideal conditions. But being a realist, I'd be on @huntnful's side betting against it.

 

[HuntHarder]

TF? I want in on this action. You are going to be storm chasing for years to pay off the bets you lost. 1.3" at 1300? I'll even bet my left testicle and I NEVER bet the left one.

 

[Packmansion]

So its settled. We can now all agree, save co ponents focus on practice and application and much less on reloading... spread the good word

He goes deep on small sample testing, but focuses on tuners with his testing. He shows both that small sample testing is bogus, and that tuner adjustments don't make any observable impact on precision. However, I consider it nearly the same as saying that powder and seating depth tweaks don't alter precision since the theory says that tuners, seating depth, and powder charge are all ways of adjusting bullet exit time to coincide with quiescent periods of barrel harmonic motion. Others might disagree but that's my take.

For those who default to saying that any truly statistically robust test would be so time and money intensive that it's just not worth doing, I implore you to think more like an engineer and less like a physicist. You can do a DAMN good test with 100rds, and that is absolutely in the realm for all of us here to afford. And think about all the subsequent ammo it will save you once you determine you can stop "tuning"! Oh whoops, I spoiled the ending.

An incomplete test is a waste of time. Also hornady has already done these tests and proven seating depth powder charge etc. have negligible impact. Basically test if you want but 3 shot groups are a joke. Youre just wasting components. 20 thousandths off. Load up 10, if you like what you see load up 100.

 

[solarshooter]

An incomplete test is a waste of time.

I'd argue that no test is ever "complete", you just have to pick a criteria to satisfy or not. I'm not asking anyone to do a proof of a physical phenomenon to 5-9s confidence like we're in a university lab or something. Again, the engineer in me always wins over the physicist, and I think there are extremely useful tests that can be run with 10s-100s of rds, which in the long run will actually SAVE far more rds than that due to killing the myth of "tuning".

20 thousandths off. Load up 10, if you like what you see load up 100.

Even this is a test procedure with an established (liking what you see in 10rds) criteria. You left off the part about what to do if you DON'T like what you see, which is also very important IMO.

There is a lot to be learned on how to actually test well, control variables, and shoot consistently enough to do a meaningful test, so I think there is additional value there. I encourage everyone to test it for themselves so they can have the same firsthand breakthroughs I did.

It's annoying we even have to "disprove" this stuff, but these myths and arcane practices are so entrenched and widely accepted. People on this forum always complain about the repetitive threads where FNGs come in and present this dogma and get in a longwinded argument just to eventually disappear or give in. But I consider this the face of progress, we are literally changing people's minds one shooter at a time. Maybe when my kids bring a new rifle to the range they won't have to listen to some idiot telling them about powder nodes and barrel harmonics.