Seating depth - does it even matter?

[solarshooter]

But I consider this the face of progress, we are literally changing people's minds one shooter at a time.

This is also why I always try to be polite to people on here. It's so easy to make someone shut down by being snarky on the internet. It may not matter to some but I get way more pleasure out of seeing someone come back and post about how they finally did the test for themselves and now they are converted vs just calling someone stupid or feeble minded and crashing the conversation. Same with people I shoot and hunt with in real life. I know that if I can get them to test these theories for themselves, refocus their practice on positions vs testing groups, etc, they will become better shooters and hunters that I actually consider an asset in the field vs a liability.

 

[TaperPin]

Keith just put out a video related to this. Interesting angle that doesn’t get talked about much.

 

[Bluefish]

The way I see it is we have huge dogma to overcome as people have used small sample sizes forever and it can be proven that this alone can cause incorrect data. I am sure some of the older chambers which have a much larger than bullet diameter, need to have the bullets out to the lands. If you don’t they can tip before getting to the rifling, causing more dispersion. Ie 300wm. The new chambers with tight bore to bullet and longer freebore probably don’t have this issue.
Also I can believe that the lands move enough that over longer strings of fire (match) that it is impossible to hold really small jump differences even if they do matter. So why not use a longer jump that is not changing much (% wise) and is providing good accuracy? Barrel life is short enough I don’t want to chase things that don’t matter enough to worry about.

 

[solarshooter]

Keith just put out a video related to this. Interesting angle that doesn’t get talked about much.

I wasn't a fan of this video. He didn't share any data and spent 90% of the time just postulating. I think he's usually very good, but he's been a little gun shy to just come right out and say that the tuning methods don't make measurable differences in his tests. For instance his video on seating depth testing had data that clearly showed no measurable effects, but he ended by narratively saying it wasn't clear and ending the video in a grey area. A huge part of his audience is benchrest and F class competitors who are HEAVY koolaid drinkers/make the koolaid so I think that factors in somewhat.

 

[207North]

Keith just put out a video related to this. Interesting angle that doesn’t get talked about much.

This one is also great and talking about seating depth testing.

 

[solarshooter]

This one is also great and talking about seating depth testing.

haha this is the one I was just talking about. Data says one thing, he says another. Great video overall though.

 

[TaperPin]

I wasn't a fan of this video. He didn't share any data and spent 90% of the time just postulating. I think he's usually very good, but he's been a little gun shy to just come right out and say that the tuning methods don't make measurable differences in his tests. For instance his video on seating depth testing had data that clearly showed no measurable effects, but he ended by narratively saying it wasn't clear and ending the video in a grey area. A huge part of his audience is benchrest and F class competitors who are HEAVY koolaid drinkers/make the koolaid so I think that factors in somewhat.

It helps to keep everything in perspective.

You do know that the Hornady boys you like to repeat, have quite clearly said their data and conclusions are aimed at average shooters with average rifles doing average things and what guys are doing differently in the accuracy sports are outside of their wheelhouse. In that context if you like Hornady’s advice and data then more power to you.

I find the probability essentially zero that every single person in the accuracy sports is wrong and simply drinking koolaid. Matches are won and lost on temperature swings and who altered their loads just enough to compensate for how it changed their tune. Not a single person who has ever won has loaded up a single powder charge without testing the tune and packed their bags. You can not believe in the process, but it’s hard to argue with the results.

I don’t think you believe what you say, or there would be no reason to shoot any groups comparing loads at all. Load one powder and one bullet and that’s the ultimate accuracy load for that rifle? You can say guys go overboard, but it’s a continuum and even you aren’t on the far extreme.

 

[solarshooter]

You do know that the Hornady boys you like to repeat, have quite clearly said their data and conclusions are aimed at average shooters with average rifles doing average things and what guys are doing differently in the accuracy sports are outside of their wheelhouse. In that context if you like Hornady’s advice and data then more power to you.

I am not a huge fan of the Hornady guys. I was first put on to the issues with small sample testing by Litz. The Hornady guys jumped on his bandwagon, IMO. Their caveat sounds like a cop out to avoid alienating too many of their customers.

I find the probability essentially zero that every single person in the accuracy sports is wrong and simply drinking koolaid. Matches are won and lost on temperature swings and who altered their loads just enough to compensate for how it changed their tune. Not a single person who has ever won has loaded up a single powder charge without testing the tune and packed their bags. You can not believe in the process, but it’s hard to argue with the results.

I don't know nearly enough about the process of every winning and losing shooter out there to say whether this is true or not. Do you have an example of a match was won or lost on a temperature swing?

Say everyone on the line is "tuning", but only 1 person wins. This is somehow proof that "tuning" is real and works?

The results are that the best shooter, often with the very best equipment available, wins. And sometimes that same person doesn't win.

don’t think you believe what you say, or there would be no reason to shoot any groups comparing loads at all. Load one powder and one bullet and that’s the ultimate accuracy load for that rifle? You can say guys go overboard, but it’s a continuum and even you aren’t on the far extreme.

I have tested powder charges and seating depths in my guns and found them to not make a difference. When I change components I actually provably see a difference on target. And the best components tend to shoot the tightest groups the most consistently. Which to me says the quality of components and combination of components matters. So I believe in that much "load dev". But again, if I start with the top shelf stuff through a top shelf barrel, it doesn't take much if any "dev" to have a top shelf gun.

 

[BBob]

This one is also great and talking about seating depth testing.

A takeaway: Short range testing is crap

 

[207North]

A lot of this is reading tea leaves.

Some of the F-Class guys are crazy. Dehydrating powder, cutting grains of powder in half with a razor blade, weight sorting everything including primers.

I also know of F-Class guys accidentally shooting their reject box of ammunition for score and doing very well in the match.

It boils down to focusing the energy at the appropriate variable. If I shoot a 1/2” gun is my time better spent on wind reading or at the bench trying to turn it into a .450” gun?

For the guy at the top of his game, that may be worth it. It doesn’t matter if the group size gain is real or not, the confidence from the effort makes them shoot better.

My rub is when people read an F-class or benchrest forum and think they need to do complicated and unnecessary steps to shoot a deer at 300y.

Does seating depth matter? Around the lands… absolutely. Big swings in seating depth, yep you will likely change group size a small amount. But shooting a 3 shot group at 2.8355 then another one at 2.8375 and claiming one is trash and one is in a Node and will shoot lights out…nah.

 

[solarshooter]

A takeaway: Short range testing is crap

Do you have an example of longer range testing with adequate sample sizes that isn't crap? Why does range play a factor? If you're going to bring positive compensation into the discussion, you're opening a whole other can of worms, and I'll just immediately ask you for any evidence of that being real.

 

[solarshooter]

It doesn’t matter if the group size gain is real or not, the confidence from the effort makes them shoot better.

I've more seen the opposite be true. People lose confidence and throw away a string because they're convinced the change in humidity has ruined their tune.

It boils down to focusing the energy at the appropriate variable.

Yes. Even IF tuning were real, the change in hit rates due to small changes in precision, especially at long range, are very small.

Does seating depth matter? Around the lands… absolutely. Big swings in seating depth, yep you will likely change group size a small amount. But shooting a 3 shot group at 2.8355 then another one at 2.8375 and claiming one is trash and one is in a Node and will shoot lights out…nah.

Do you have any data for this? I could believe that the pressure curve changes significantly going from jam to jump. And then maybe the velocity and thus recoil changing precision. I really don't know, I don't ever jam or care to jam so I don't have much personal data.

 

[207North]

I've more seen the opposite be true. People lose confidence and throw away a string because they're convinced the change in humidity has ruined their tune.

That is fair. What I have seen a lot is people really focus and shoot well with the “good” load. Then they get to the load they do not expect to perform, they just send them and end up shooting a bad group.

Do you have any data for this? I could believe that the pressure curve changes significantly going from jam to jump. And then maybe the velocity and thus recoil changing precision. I really don't know, I don't ever jam or care to jam so I don't have much personal data.

No data, but I have experienced multiple carbon rings that essentially turn .005 off the lands into a jammed load. When this happens velocity goes haywire and it becomes tough to sort out. If you are right on the edge of contacting carbon it would show up on paper. Now I stay a minimum of .020 off and no longer have those issues.

 

[207North]

I should add that in addition to seating no closer than .020 off I clean much more frequently.

 

[huntnful]

I've more seen the opposite be true. People lose confidence and throw away a string because they're convinced the change in humidity has ruined their tune.


Yes. Even IF tuning were real, the change in hit rates due to small changes in precision, especially at long range, are very small.


Do you have any data for this? I could believe that the pressure curve changes significantly going from jam to jump. And then maybe the velocity and thus recoil changing precision. I really don't know, I don't ever jam or care to jam so I don't have much personal data.

How do you feel about neck tension? And do you consider part of “tuning”, or general initial load work. And does it have an impact?

I have a pretty compelling examples that it can make a good bit of difference.

 

[Harvey_NW]

Do you have any data for this? I could believe that the pressure curve changes significantly going from jam to jump. And then maybe the velocity and thus recoil changing precision. I really don't know, I don't ever jam or care to jam so I don't have much personal data.

Anecdotal, but in testing over the years in Tikka actions I have noticed pressure signs will show up at a lower charge when I've tested .010" off the lands. I can usually get a little more by bumping back to about .050", so that's where I load now to stay well out of carbon fouling, and haven't had any issues since.

How do you feel about neck tension? And do you consider part of “tuning”, or general initial load work. And does it have an impact?

I have a pretty compelling examples that it can make a good bit of difference.

I was just about to bring this up, Alex Wheeler says you'll never get the most out of long range precision if "you're on the wrong tune", and has shown some pretty convincing test targets of vertical shrinking almost 50% ES by going from .001" to .004-5" of interference. He says most of the magnums he's tested all do better with more neck tension. This is ultimately why I started using mandrels/expander balls at .003" under bullet diameter, for ~.004" interference with springback. Very interested in what you've found.

 

[mxgsfmdpx]

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.

For real though.

I actually shot gay ass bench rest for years and years. 20+lb guns literally built for this with STUPID amounts of time into the loads, guns, shooting conditions etc. I’m a verified “1,500 yard VHA member” with multiple witnesses, the list of “accolades” goes on but who cares…

Not a single person I’ve ever shot with in real life would make that claim or take that bet lol.

 

[solarshooter]

I clean much more frequently.

This I don't do. Haven't had issues in 1000s of rds without cleaning. At most a dry patch if there is literal junk in the bore like pine needles or visible crud from carrying in the field. Otherwise nothing.

Edit: I'll add that for some guns, abrasive cleaning with JB/Kroil has helped their accuracy a lot. In these cases they were new barrels that were behaving inconsistently, and I'm guessing had burrs or sharp edges that the abrasive clean fixed. But it's usually a one time thing. If I were to ever clean, it would be a deep clean with abrasives back to bare metal, with the intention of shooting for 100s of rds after.

How do you feel about neck tension? And do you consider part of “tuning”, or general initial load work. And does it have an impact?

I don't mess with it personally, I use standard Redding resizing dies which typically yield 0.002-0.003" of tension. I want the bullets to be securely held but I don't want to grab too hard or have any weirdness with seating/galling. So standard dies it is. Plus they are much cheaper.

Please share your examples if you have them, I'm always eager to see data.

I think neck resizing ONLY is a big mistake for any type of shooting period.

Anecdotal, but in testing over the years in Tikka actions I have noticed pressure signs will show up at a lower charge when I've tested .010" off the lands. I can usually get a little more by bumping back to about .050", so that's where I load now to stay well out of carbon fouling, and haven't had any issues since.

This makes intuitive sense. Also, measuring "jam" is not a perfect art. I've seen and done at least 4 methods, none of which are perfectly precise or repeatable. So in some cases what you think is slight jump is actually jam, or vice-versa. I always start 0.020-0.030" away from lands or more.

I was just about to bring this up, Alex Wheeler says you'll never get the most out of long range precision if "you're on the wrong tune", and has shown some pretty convincing test targets of vertical shrinking almost 50% ES by going from .001" to .004-5" of interference.

Did he by chance demonstrate this with 3-5 shot groups?

 

[207North]

This I don't do. Haven't had issues in 1000s of rds without cleaning. At most a dry patch if there is literal junk in the bore like pine needles or visible crud from carrying in the field. Otherwise nothing.

Edit: I'll add that for some guns, abrasive cleaning with JB/Kroil has helped their accuracy a lot. In these cases they were new barrels that were behaving inconsistently, and I'm guessing had burrs or sharp edges that the abrasive clean fixed. But it's usually a one time thing. If I were to ever clean, it would be a deep clean with abrasives back to bare metal, with the intention of shooting for 100s of rds after.

I originally started cleaning my match gun every 500 rounds. Cleaning the baked on carbon was quite the process and took hours. Then I started cleaning every 300 rounds. It became much less involved. Now I do 10-20 passes every 100 rounds. It takes a couple minutes and seems to work for me in a match setting.

 

[solarshooter]

Just googled Alex Wheeler neck tension and found a thread on accurate shooter of him "tuning" a 300 PRC and I think I'm going to catch alzheimers if I read too much of this stuff:

The next combo I tried was H1000 and 230 Berger hybrids .020 off.
77-2907
77-2901
77.4-2923
77.8-2946
78.6-2950
79-2958
79.4-2971
79.8-3002
80.2-3000
80.6-3036
This ladder looked great, 2 obvious nodes, 2901-2923 held .658" of vertical at 600yds, 2971-3002 held .714". 3 shots in each node. This is the combo this barrel is going to like, 3 shot groups around each node at 1k is the next step. Then fine seating and hopefully its done.

Ran the upper node at 1k at -9 this am. Forgot the ammo in my truck last night so I did my best to warm it up. When things get this cold they start to fight you a bit. ES was a little higher than it has been which I think accounted for the one dropped shot, mirage was pretty bad too so who knows. Even still it shot 2 groups in the 3s for vertical, one in the 1s, and one in the 5s. It seemed to run about 10 fps higher this time out. My aim dot is 4".

One thing to note which may help some of you guys is that this thing required a total re tune once I fired the brass. Different seating depth and powder charge. I have seen this before in other cartridges especially magnums. Even the node itself moved. Most of the time we don't have to deal with this because we are playing with cartridges that require fire forming so you never actually shoot new brass. Just fyi.

Absolute horror show of small sample testing, drawing shapes on targets, eliminating fliers, making assumptions, finding different behaviors when testing again and coming up with elaborate theories to explain it away. The replies and comments are even worse. I seriously don't understand how anyone reads this and believes it.