Chasing the lands is stupid... What do you think?

[dgeesaman]

I read only a little bit of this thread and I got a few things from it:
1) you (Erik) don’t agree that keeping a constant distance from touch/lands is effective at keeping a tune during the life of a barrel. In my limited experience I agree.
2) Therefore you don’t track touch lengths. But to call any other method “stupid” is arrogant and unfounded because you only talked about how your method works. You didn’t invalidate anything about that method.
3) You are not blind to the location of the lands, you instead jam a bullet with a dummy round to get your maximum practical seating depth. So you use a different measurement to get initial seating depth than touch. (As a Hornady tool user, my measurement method is somewhere between touch and jam because I use firm pressure on the gauge). But you only measure it in the beginning because the safe jam depth only gets safer with throat erosion and from that point forward you chase the tune.
4) I like your strategy for following the seating depth tune. It’s easy and does not spend many rounds. I will try it. I may track the tune on a barrel I have and measure the lands location also using my Hornady tool just to see where each of those numbers go during the life of the barrel.

 

[Nature Boy]

4) I like your strategy for following the seating depth tune. It’s easy and does not spend many rounds. I will try it. I may track the tune on a barrel I have and measure the lands location also using my Hornady tool just to see where each of those numbers go during the life of the barrel.

If you did that, and it shows that there isn't a 1:1 relationship between touch and your accuracy node as the throat wears, then you will have some empirical evidence that Erik's method has validity.

 

[Ccrider]

Once you find the correct seating depth, does anyone move away from the lands if their rifle looses tune as the barrel ages. I instinctively load longer as Eric suggest, and everything falls right back into place. I figured everyone did the same.

Knowing where touch is helps to track barrel wear but I have not been able to get any rifle to shoot well at touch. So, I prefer backing off of a hard jam. For my deer rifle, I back off .02 and work back from there. For benchrest, I work off in .003 increments and then fine tune.

Is this really that complicated?

I wish someone had the quick solution for reading the wind. Now that would be helpful.

 

[Bc'z]

I like the white cheddar powder on my popcorn.
I've discussed seat

Once you find the correct seating depth, does anyone move away from the lands if their rifle looses tune as the barrel ages. I instinctively load longer as Eric suggest, and everything falls right back into place. I figured everyone did the same.

Knowing where touch is helps to track barrel wear but I have not been able to get any rifle to shoot well at touch. So, I prefer backing off of a hard jam. For my deer rifle, I back off .02 and work back from there. For benchrest, I work off in .003 increments and then fine tune.

Is this really that complicated?

I wish someone had the quick solution for reading the wind. Now that would be helpful.

If your confined to a magazine length and have a specific COAL you can only go deeper to the next accurate seating node.

 

[F Class John]

If you can repeat the jam number to the fraction of a thousandths like I can finding "touch", then I say why not....it's the same thing. The reason that I take the extra 18.7 seconds to find "touch" after every cleaning, is so that I have an idea as to when a "checkup" is called for(this of course, once the load is developed). The results of that test may very well indicate leaving seating at "2.871" is best, or it may not. It might indicate the precision will be best with a 1:1 ratio move, or it may not. I do what I do so as to attempt to not be "surprised" by a poor group that I would've otherwise had control over had I just took the time to run a test. I guess I just can't afford to wait until it underperformed in a match to get my attention.....Likely a mental flaw. Trying to eliminate big groups when conditions aren't the limiting factor is how you agg. It's work, and i do the work....and still find things I could've done better or more thorough.

I think we all "chase the seating node" no matter what skinning knife is used.

Tom

He's not saying to chase the jam, he's saying the first time you do load development you go to jam, then load backwards from there and never measure again. If your load development had your node in a 2.125 - 2.129 range for instance, you'd shoot it at 2.128 and periodically test at 2.129 or 2.130 and see if the group tightens up. If it does then that's your new seating depth and if it's worse than keep shooting at 2.128 until you test again or the barrel is cooked. It's a totally different approach and doesn't involve any kind of chasing. Its simply about staying ahead of the node by testing just outside the node to see if it moved or not. Reminds me of keep it simple. That's his whole point.

In a nutshell, the group should not tighten up, it should stay the same. If the group stays the same further out, move out. If group opens up further out, stay where you are at.

 

[dmoran]

I’m not sure the community got stronger, but he damn sure got attention heck poor old Donavan about lost his mind.......................................

The blind leading the blind, your caught up in there old South Prairie Jim............
Ask your competition next time your at DCR how stupid they see it (some of them are already laughing).

 

[dgeesaman]

If you did that, and it shows that there isn't a 1:1 relationship between touch and your accuracy node as the throat wears, then you will have some empirical evidence that Erik's method has validity.

I think his method has plenty of validity.

But nothing I’ve seen has invalidated the other methods.

I guess I’m surprised that nobody has taken this data before. It’s not hard. Or if you have a barrel that’s not precious, just do a full seating depth work up every couple hundred shots and see if you can follow the node. Then compare that to the touch or hard jam length at each work up. Compare the data over the life of the barrel.

David

 

[davidjoe]

This post coincides with the Bulletin’s detailed story on Peter Johns’ fantastic rise to the top of TR competition, a great read. Peter could have hidden the ball or sent us down rabbit trails. He says he eliminated many steps that were not improving accuracy, through controlled experimentation. “Full circle” appears in the text.

Careful readers have gleaned that Bryan Litz suspects our barrels are too thick to be as affected by vibrations as conventional wisdom on nodes suggests they are. Three relatively younger guys that do succeed on the firing line quietly floating a trial balloon on whether certain steps help or don’t help make ammunition more consistent or shoot better, shot to shot. (Obvious hint - It’s mainly wind calling -and BC “make up” to the extent you can’t at least in bullseye. When the throat erodes switch to long bodied scenars.) We can all iron out an accurate enough rifle.

 

[MikeMcCasland]

 

[CharlieNC]

Careful readers have gleaned that Bryan Litz suspects our barrels are too thick to be as affected by vibrations as conventional wisdom on nodes suggests they are.

I just installed a new heavy 22in barrel on my 308. Ran a powder charge ladder and found two nice flat nodes on this short, heavy barrel. Maybe not heavy enough? Interestingly the two nodes were exactly where Dan Newberry's old tattered spiral notebook said they would be based upon his working up loads for many clients, shooting many different rifles. This is not coincidence, and reflects just how little we really understand.

 

[davidjoe]

Two flat “nodes” that are the same charge for many different barrels, to the extent they can be predicted and written down, does not show every barrel is different and needs a work up. Tends to show the opposite.

 

[CharlieNC]

Two flat “nodes” that are the same charge for many different barrels, to the extent they can be predicted and written down, does not show every barrel is different and needs a work up. Tends to show the opposite.

Exactly my point. I like many get too deep trying to understand barrel harmonics, optimum barrel time, etc. Dan is not a rocket scientist, but has decades of experience that is usually right.

 

[rjtfroggy]

This is really only the second post I've from Mr. Cortina and I will say he gets a lot of attention. One post 110 pages and this one already approaching 10 but let's be honest how many of you old farts are going to change your ways.
I know I'm not because without all the hoop-a-la this is basiclly what I've been doing all along so why change now.
I'm going to keep reading because I like all the back and forth that all amounts to the same thing.
Thanks for the amusement.

 

[gunsandgunsmithing]

Two flat “nodes” that are the same charge for many different barrels, to the extent they can be predicted and written down, does not show every barrel is different and needs a work up. Tends to show the opposite.

Becoming very familiar with using a tuner and seeing how little adjustment there is between completely in to out of tune and back in again, puts"a go to load" more into perspective. It happens often, believe it or not. I'd say about 1 in 4 guns can shoot a known load for a given chambering, with little or no load adjustment at all...maybe more than that.

Known loads put you in the right area, with the right pieces to the puzzle, already in place. A small tweak of powder, seating depth or just the tuner, can almost always bring a gun into a very high level of tune.

 

[davidjoe]

This is really only the second post I've from Mr. Cortina and I will say he gets a lot of attention. One post 110 pages and this one already approaching 10 but let's be honest how many of you old farts are going to change your ways.
I know I'm not because without all the hoop-a-la this is basiclly what I've been doing all along so why change now.
I'm going to keep reading because I like all the back and forth that all amounts to the same thing.
Thanks for the amusement.

If accurate shooter will ever put on a Comedy Central Channel style “Roast”, I’ll nominate Erik to be the first victim. Erik’s name is on the Texas Long Range Championship Perpetual Trophy for F-Open, the most times. Moreover, he teases the leaders by falling behind until the end.

My wife once leaked out to Erik that I didn’t talk about winning the match around the house, only about beating Erik. He doesn’t even make the Bayou club LR matches to practice, just shows for state to win.

 

[JJMoody]

First of Erik’s videos I’ve seen. I now read all his posts in his voice...

 

[bozo699]

my seating die sits on the ojive of the bullet and holds the case at the base. So if i bump a case .001 or even .015 the relationship of the bullet to the lands (jump or jam measurement) is the same no matter what i do. I could use 3 different sizers and my jump/jam would be the same every time.

Spot on Dusty!...
Wayne

 

[bozo699]

No it's not , If your case headspace is 5 to 7 thou shorter then your chambers headspace . The cartridge is moving in the chamber that much . So if some of your shoulders are bumped .002 while others are bumped .005 to .007 . That is a .005 variance of where your ogive will be in relation to the shoulder because you are seating from the head of the case . Thats a big deal because the case headspaces off the shoulder not the head of the case . So when the firing pin pushes the case forward and the case shoulder stops on the chamber shoulder . That case shoulder to bullet ogive is what sets your jump , touch or jam length not your case head to ogive measurement .

Put another way , Lets say you only neck size and the case is a semi tight fit to the chamber . When the firing pin hits the primer the case has no room/extra space to move forward in the chamber so your bullet when fired is at the same place in relation to the lands as when you originally seated the bullet or recorded your lands measurement . Now take that same case and bump the shoulder back .005 then seat the bullet to the same COAL as before . Now when the firing pin hits the primer is pushes the case that extra .005 forward you bumped the shoulder resulting in the bullet moving forward that same .005 actually changing your jump , touch or jam measurement that same amount .

It's VERY important if you are only adjusting your seating depth by just a few thou that your head to should datum distance is very consistent from case to case . If not adjusting just 2 or 3 thou is a waste of time because your case can move that same amount in the chamber . Meaning cases with a .002 bump will move that much while cases with a .005 bump will move that much more negating or doubling your .003 adjustment .

If your jumping the bullet you would be correct,.... however the op is talking about being in the lands as with Dusty. You could shove the shoulder back .100 and it wouldn’t matter the bullet is still in the riflings. I do it all the time fireforming 6br cases to improved versions, usually about .100. So far quite a few of the people responding must not have paid very close attention to the op’s video!
Wayne

 

[bozo699]

I think what Eric is trying to say is after finding the jam measurement he will not measure this again. He will only adjust his seating depth from the accuracy node measurement. He doesn't care how much the lands have worn.
Is this correct, Erik?

You actually listened to the video
Not picking on you I’m just surprised how many people didn’t comprehend it.
Wayne

 

[KY_Windage]

I think we arrive at the same place. I take a measurement to the point of "firm touch," then if I am .003 back from that, I call that a ".003 jump." If I am .003 past that point, I have a ".003 jam." I know a lot of other people who use the same nomenclature.

So would rather that Eric call his starting point the "stick point," or something else besides the "jam point," but it does not matter so long as we all know what the other means.

From the "firm touch" point I go into the lands whatever shoots best according to trial and error. I don't care where the "stick point" is because I am not going to get near it, or, if I think I might be, I will test by loading and ejecting a couple of rounds (while keeping the barrel pointed straight up ).

I suspect we would arrive at the same node and be equally happy. I also would simply decrease my seat depth if I thought wear in the barrel warranted it. It is all good, and thank you, Eric, for posting the video.