Would this be fair to say?

Years ago, I found a way to make almost any rifle shoot much better with very little work. Never got a chance to capitalize on it one bit- life happens- but I've kept it under my hat for over 20 years and I'll be damned if I'm giving that secret out until I've exhausted every means to get it patented and do something with it.

Top competitive shooters aren't giving away all of thier hardest learned secrets. That would be stupid.

They also aren't here talking about it. They're over on youtube making money on views by stirring up heated debates, controversy and confusion.

Eric Cortina isn't winning matches using ammo he loaded while doing a live youtube video like he wants you to believe. I've seen him distrectedly fumbling bullets while stuffing them in the necks, drop a loaded round, and put it in with the rest.

That said, We've got some pretty **** good shooters here that do freely talk about what works for them, and its easy to see the patterns when you get enough of a sample size.

Some bullets like jump, some don't and it has to do with the shape of the bullet ogive where it meets the bearing surface. But its not as simple as it sounds- Several things to consider at once- bullet ogive shape and jump distance influences pressure curve shape influences node characteristics influences accuracy.

The other is accuracy of bullet placement in the bore axis (both dimensional and center of mass of bullet to consider). Bullet shape and forcing cone shape have a definite influence on this- tangents go into the cone straight easier than secant, so they don't have to be jammed as close. Throw all these things into the mix in one violent explosion and its easy to see how people get confused about what's influencing what.

So like I said, look for patterns, and try to keep separate things separate so you're not chasing your tail
Jam is NOT the be all and end all of seating depth.
BR shooters use different chambers and different bullets in comparison to F-Class shooters. Chamber design influences seating depth just as much as bullet type.
Rarely have I mentioned on here exactly which bullets for competition I'm using, but I will tell you that I never jam because I never find it to make much difference to my aggregate scores. When I'm shooting strings of 50-80 bullets, I don't care that a jam resulted in a few very tight groups while the load that was .010" off produced 1/4 MoA every time it was shot…which is gonna be used?!
Yes secant ogive is different to tangent, but the seating depth is still what is most important, tuning after this with powder and primers is rarely the deal breaker.
Anyway, I'll let you believe that jam is king.

Cheers.
 
Jam is NOT the be all and end all of seating depth.
BR shooters use different chambers and different bullets in comparison to F-Class shooters. Chamber design influences seating depth just as much as bullet type.
Rarely have I mentioned on here exactly which bullets for competition I'm using, but I will tell you that I never jam because I never find it to make much difference to my aggregate scores. When I'm shooting strings of 50-80 bullets, I don't care that a jam resulted in a few very tight groups while the load that was .010" off produced 1/4 MoA every time it was shot…which is gonna be used?!
Yes secant ogive is different to tangent, but the seating depth is still what is most important, tuning after this with powder and primers is rarely the deal breaker.
Anyway, I'll let you believe that jam is king.

Cheers.
Are your first and last sentences directed at me? I don't believe jam is king.

There's WAY more to it than that, as I tried (apparently unsusccsessfully) to illustrate earlier. Seating depth not only changes the presure curve because of how soon after ignition pressure from bullet engraving starts, but also effective starting combustion chamber volume. Immediately after ignition you get not just one pressure spike, but several.

Bullet shape (and leade angle) also affects this time/pressure curve, as a tangent ogive eases into the riflings slightly less abruptly than secant, slightly muting the peak off the spike.

If one were to look at the map of the pressure curve, you would see the pressure spikes from the very first flicker of flame from the primer, the ignition of the first powder, the easing of pressure for a tiny microsecond after bullet movement before rifling engagement, another spike at bullet's first contact with rifling, a very slight plateu of pressure when the brass expands in the middle, then the big hit of pressure when a majority of the brass expansion is stopped by the chamber wall and full engraving starts. Exceeding the plastic limit of the brass (vs not) will also change the curve.

The rest of the pressure curve from there on is dedermined by the powder, bullet, and barrel correlation, burn rate and barrel temperature. I could go on and on about this and left out alot but am trying to simplify it for brevity.

My thoughts about manipulating this curve and its peaks/ valleys in a way that produces accuracy have been put to the test, and it has worked for me.

Seating depth is just one of the key ways to manipulate this curve via volume and pressure peak timing changes.

Change one aspect, and you change them all.

This really hasnt even begun to talk about bullet to bore entry relationships with regards to the different shapes /hardness of bullets. Or how pressure, and what it does to the brass, and the brass-to bullet relationship during entry into the riflings. Another day.

Edit: I do think you're onto something starting seating depth changes first. Might try it.
 
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My thought is......why bother with different charge weights if you don't know where the bullet likes to sit? Or for that matter, if the barrel likes that bullet at all? I find seating first, then move to 2 shot ladder tests at no less than 80% distance I figure for my max. That's usually 600 to 800 yards. If you read your ladder correctly, I think you end up with a very predictable load. I've only once gone back and adjusted seating after doing the ladder. Just my method, like I said....we all get there, just different paths
Different charge weights. The reason for me is I am looking for that max charge. I feel that I need to know if the rifle will do the velocities I want or should be able to make. The velocity may not be there, so I am move to a different load, bullet. I already kind of know what bullet weight I am going to use in that rifle, but velocity may not be there again. So adjustment may be needed.
Several of my reloads in different rifles are over the manual stated max.
I'll back the powder load back down and change primers. I increase the charge weight quicker at that time. It's a little hard to figure just what charge weight and primer is going to be use yet. With that in the later stages I am adjusting my seating of my bullets, because I have a combination of primers, powder, bullet, velocity and grouping. I find tune at that stage. To me the final is adjusting seating dept to see if it's group better. We change things to see what is better. Don't get mad, it's discussion , not to get mad about. Learn to roll with the bunches. Possible learn at the same time.
 
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Different charge weights. The reason for me is I am looking for that max charge. I feel that I need to know if the rifle will do the velocities I want or should be able to make. The velocity may not be there, so I am move to a different load, bullet. I already kind of know what bullet weight I am going to use in that rifle, but velocity may not be there again. So adjustment may be needed.
Several of my reloads in different rifles are over the manual stated max.
I'll back the powder load back down and change primers. I increase the charge weight quicker at that time. It's a little hard to figure just what charge weight and primer is going to be use yet. With that in the later stages I am adjusting my seating of my bullets, because I have a combination of primers, powder, bullet, velocity and grouping. I find tune at that stage. To me the final is adjusting seating dept to see if it's group better. We change things to see what is better. Don't get mad, it's discussion , not to get mad about. Learn to roll with the bunches. Possible learn at the same time.

I'm not mad at all, I think maybe you replied to my remarks but were directing to somebody else? Anyway, just sharing what I do, not that it's the only way....just the way I do it. Works for me, I'll keep doing that way
 
What do you use to meter and weigh powder? How large are your powder increments when testing different charge weights? How large are your changes in seating depth? Thanks

Just a plain old RCBS 1500. I usually pick the longest possible COAL for my application and work back .003 at a time for .012 or .015 difference. Sometimes that's from jam or touching or if the situation requires, magazine length. I can normally find a good depth in that range and then work from there. Powder increments depend on the cartridge being loaded for. My course adjusting for 223 like Cases is usually .3gr/ 308 sized cases .5gr and magnums 1gr at a time during the ladder testing portion. Once the vertical comes together at range, I pick the load that lands in the middle of tightest vertical spread and run with that. Very little development is needed after that. Sometimes fine tune, but more often than not the load turns out very predictable and repeatable......that's the name of the game and the beauty of doing a ladder test.
 
Are your first and last sentences directed at me? I don't believe jam is king.

There's WAY more to it than that, as I tried (apparently unsusccsessfully) to illustrate earlier. Seating depth not only changes the presure curve because of how soon after ignition pressure from bullet engraving starts, but also effective starting combustion chamber volume. Immediately after ignition you get not just one pressure spike, but several.

Bullet shape (and leade angle) also affects this time/pressure curve, as a tangent ogive eases into the riflings slightly less abruptly than secant, slightly muting the peak off the spike.

If one were to look at the map of the pressure curve, you would see the pressure spikes from the very first flicker of flame from the primer, the ignition of the first powder, the easing of pressure for a tiny microsecond after bullet movement before rifling engagement, another spike at bullet's first contact with rifling, a very slight plateu of pressure when the brass expands in the middle, then the big hit of pressure when a majority of the brass expansion is stopped by the chamber wall and full engraving starts. Exceeding the plastic limit of the brass (vs not) will also change the curve.

The rest of the pressure curve from there on is dedermined by the powder, bullet, and barrel correlation, burn rate and barrel temperature. I could go on and on about this and left out alot but am trying to simplify it for brevity.

My thoughts about manipulating this curve and its peaks/ valleys in a way that produces accuracy have been put to the test, and it has worked for me.

Seating depth is just one of the key ways to manipulate this curve via volume and pressure peak timing changes.

Change one aspect, and you change them all.

This really hasnt even begun to talk about bullet to bore entry relationships with regards to the different shapes /hardness of bullets. Or how pressure, and what it does to the brass, and the brass-to bullet relationship during entry into the riflings. Another day.

Edit: I do think you're onto something starting seating depth changes first. Might try it.
My answer was directed towards what was described as to what BR shooters do.
Have tested for 30 years, seating depth always trumps powder testing first. Using a middle load doesn't change this, it just makes the transition to engagement a little nicer, we're only talking a 2-3gr lower charge weight…and yes, the same precision is used to meter and check this charge weight.
Have proven that once a seating depth for that particular bullet is found, it may take no fine tuning or very minor tuning to keep it there regardless of powder used.
Many F-class guys are finding this too, Berger being the most used, but I have been using Nosler CC's for a long time and recently played with RDF bullets in 6.5, 30 and 33. Berger bullets are too hard to get here in Australia.

Cheers.
 
My answer was directed towards what was described as to what BR shooters do.
Have tested for 30 years, seating depth always trumps powder testing first. Using a middle load doesn't change this, it just makes the transition to engagement a little nicer, we're only talking a 2-3gr lower charge weight…and yes, the same precision is used to meter and check this charge weight.
Have proven that once a seating depth for that particular bullet is found, it may take no fine tuning or very minor tuning to keep it there regardless of powder used.
Many F-class guys are finding this too, Berger being the most used, but I have been using Nosler CC's for a long time and recently played with RDF bullets in 6.5, 30 and 33. Berger bullets are too hard to get here in Australia.

Cheers.
You got me a thinking. I know that wont' get me to far, but. So you are saying use a middle or mild load and work on seating dept in relation to lands. That would require at least 5 shots per seating to determine the what works in the rifle. If bullets are changed them back to square one? Your ogive has changed. If using a comparator to set up the seating of the bullet being in the same place in relation to lands. Would that work to be consistent to the lands? Not having to go back through seating depth again. Being why I am asking this question. The rifle I am getting ready to work up loads, there not much out there for reloading guides. It's being a 6mm/280AI chambering. I figured that by running powder loads by increasing them is changing my POI almost every time. I can see the ladder test during the run up on powder. So I feel it would be almost impossible to determine seating depth until a load was determine. If you already have loading for that chamber from a manual, then it's a different story. I can see that adjusting the seating right off. Presently there isn't middle load. Again going back to bullet and there ogive. I think that changing bullet changes the ogive some. So you are back to square one 1. I am not sure as to which bullet I going to use yet. I thinking Hammer 100gr hunter, but there others out there. Hammer has lighter bullet in 6mm, but not heavier. Others go up to 108gr or close to that. I am running a 7 to 1 twist rate too. What you put forth has gotten me a thinking, and created some question. Please advise or anybody else as that does.
 
@MikeMatteson,
I see your dilemma, but there are formula's and reloading tools out there that can be used to help. QL or GRT can be very useful to determine a suitable powder and a max load.
Once you find these parameters it's a simple step to use a load 3gr below the recommended max and use that to find best seating depth.
Yes, if you change bullets then you need to retest, my 338-416 Rigby Improved 45° was a huge gamble and after the first iteration was not what I envisioned, re-development took 18 months and cost quite a lot. I don't regret the decision at all, as I wanted to get 3200fps from a 300gr pill and I did with some change.
Anyway, back to the issue.
As you realise that seating depth takes less components to get real world results, you will be very happy. Also, a 3 shot string is just fine for seating depth, as the results are normally quite different and the sweet spot will be easily seen. It normally tightens remarkably.
I always go .005" increments to start from touching in my target rifles and .010" off with precision hunting rifles.
My .222 Rem was very finicky until I did a seating depth test, it was amazing how much difference it made. That thing has all bullets touching at 100, wish my 22-250AI shot as well, but 1/4 MoA is still pretty good.

Cheers.
 
I find that I can usually get higher muzzle velocity at lower max chamber pressure, and lower Es, with big jumps. So I usually start with 0.160" jump, and find a best charge weight with that jump.

After finding best charge weight for 0.160" jump, I check shorter jumps to see if there's any significant improvement. If I do find a shorter jump that works better, I'll typically try a few charge weight tweaks at the shorter jump, to see if there's any improvement at slightly higher or lower charge weights.

More than half the time, I end up sticking with the 0.160" jump.
 
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If you are anywhere close to the right powder for cartridge/bullet, then seating depth is bigger to results.

So when you calibrate anything, you first make your coarse adjustments, before moving onward to finer adjustments. Right?
With an old radio you press the coarse radio buttons to get near a station, and then you use the tuning dial to lock in a station.
View attachment 448682
Seating represents the coarse setting buttons, The fine dial is powder (right to the kernel).
Let's say you're looking for THE strongest station.

Your method has you randomly press any button once, and then dial around it until locking in a nearest station. When you find it, you think that's it, my node. And then with a bazaar thinking, you again press that random seating button, about half way, thinking you might find an even stronger station with that. Of course most of the time it just muddles up reception, and you come to the conclusion that you have to go back where you found a node earlier and stay there.
But is that really your strongest station? It just happened to be near a point you pulled out of your butt like that?

With seating first, you press every button on the radio first, and hopefully get near a couple strong stations.
From a coarse setting that seems strongest, you then fine dial in a lock on one.
You can horse around with the settings all you like, but chances are you've directly found the strongest station already.

Now you might be confident in some foreknowledge. At a bar, you heard "I always start with the 4th button from the right".
But just ask yourself: why would that be correct? For YOU?

I totally agree with your radio analogy of using a coarse adjustment first, then a fine adjustment. I'm curious why you consider seating depth as the course adjustment versus powder charge? I've always done the opposite with good success.

I have watched Scott Satterlee's video on doing seating depth first and find it interesting. My thoughts around his 2.0 method are that it would probably work if you were using a known cartridge/barrel/load that you have used several times before, such as his PRS gun. I don't know how you would pick a random load to work on seating depth if you started with a new rifle in a different cartridge you've never used before. Many of my rifles have good nodes that are loaded above listed "max" charge weights but I would never start at a max charge to test seating depth.

Scott Satterlee 2.0 method of reloading Philosophies and Evolution
 
@MikeMatteson,
I see your dilemma, but there are formula's and reloading tools out there that can be used to help. QL or GRT can be very useful to determine a suitable powder and a max load.
Once you find these parameters it's a simple step to use a load 3gr below the recommended max and use that to find best seating depth.
Yes, if you change bullets then you need to retest, my 338-416 Rigby Improved 45° was a huge gamble and after the first iteration was not what I envisioned, re-development took 18 months and cost quite a lot. I don't regret the decision at all, as I wanted to get 3200fps from a 300gr pill and I did with some change.
Anyway, back to the issue.
As you realise that seating depth takes less components to get real world results, you will be very happy. Also, a 3 shot string is just fine for seating depth, as the results are normally quite different and the sweet spot will be easily seen. It normally tightens remarkably.
I always go .005" increments to start from touching in my target rifles and .010" off with precision hunting rifles.
My .222 Rem was very finicky until I did a seating depth test, it was amazing how much difference it made. That thing has all bullets touching at 100, wish my 22-250AI shot as well, but 1/4 MoA is still pretty good.

Cheers.
Thanks for the insight. I'll change my ways. I also have a QL disk and have had for a year or more now. Haven't used it yet, but will put it into play when needed. I could see this come in needing additional info. I can pull enough info from reloading manuals to come very close to what I needed. Also a safety factor too.
I have about 45 pages of note or imput either from me, or I read, or direct from people here or people that have written about reloading. With the net, you can do a lot of runnng around and never leave the chair.
Thanks again.
 
I'm curious why you consider seating depth as the course adjustment versus powder charge? I've always done the opposite with good success.
When you do actual full seating testing, you will understand.
There is no amount of powder change that even comes close to the span you'll see from seating testing.

What over 99% of people get wrong about seating is thinking it's tuning.
Once you understand that it's not tuning, but a major prerequisite to tuning, it all goes to logical.

There are 4 separate phases to load development.
1. PREREQUSITES. This is optimum CBTO, optimum primer for your striking, brass fire forming, optimum sand & fill in your bags, etc.
2. POWDER TUNE. This is OCW, no matter how else you think it.
3. BARREL TUNE. With a barrel tuner you can put barrel tune on top of powder tune, otherwise you likely depart a bit from OCW for barrel tune, with ladder testing at range. Where you can't have both at optimum (which is normal) your choice of either should be range/use dependent.
4. COLD BORE ACCURACY DEVELOPMENT. This is a tweaking of powder to compensate for what ales your system. It can wreck a hot bore tune, so decide what matters for you. But if you're a LR hunter, you should engage this phase so that you're at least informed.
 
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When you do actual full seating testing, you will understand.
There is no amount of powder change that even comes close to the span you'll see from seating testing.

Are there any links you can post to explain what full seating testing is? Is it the same or similar to Satterlee's 2.0 method? I have typically done a charge weight ladder followed with the Berger method and then narrowed down to a window of 0.005-0.010. Seating it to the longer depth to allow for some throat erosion without having to change my CBTO.
I'm starting to work up a load for a short barreled 6.5 CM and wouldn't mind testing a different method.
 
Berger does not have you do the testing from a tune.
That wouldn't work as you would come in & out of tune with the testing.

Your method fits my earlier radio analogy.
You do your ladder, which is barrel tune, with seating pulled from your butt.
Better is to do tuning with at least optimum coarse seating, a prerequisite, so that you won't throw up shotgun patterns to interpret.
 
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