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  #31  
Old 10-28-2017, 11:05 PM
Salavee Salavee is offline
 
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What about this procedure ? Anyone tried it ?

http://optimalchargeweight.embarqspa...der/4529811360
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  #32  
Old 10-29-2017, 10:18 AM
flange flange is offline
 
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Originally Posted by Salavee View Post
What about this procedure ? Anyone tried it ?

http://optimalchargeweight.embarqspa...der/4529811360
This is the process I use and have had good luck with. I test at 200 yds. Only reason is that's what my range at home most readily accommodates. And I will typically start in the middle of published data.

Edit: Only downside might be the shifting of position for the different targets.
Maybe not as consistent as off the same same position on the rest each time.
I haven't seen this as an issue.

Last edited by flange; 10-29-2017 at 10:20 AM. Reason: Add info
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  #33  
Old 10-29-2017, 10:24 AM
crazy_davey crazy_davey is offline
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Originally Posted by 6.5x47 lapua View Post
you don’t fully understand the information I give you.
That's pretty obvious. But, that doesn't stop Don from typing
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  #34  
Old 10-29-2017, 10:30 AM
elkhunter11 elkhunter11 is offline
 
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Quote:
Originally Posted by 6.5x47 lapua
you don’t fully understand the information I give you.
That would explain the badly messed up terminology that he keeps posting .
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  #35  
Old 10-29-2017, 11:21 AM
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EZM EZM is offline
 
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I've always tried to ensure that any experiment I do has variables controlled - the condition of the barrel (temperature) has always been on my mind when doing something like this.

Do you start your testing using a cold barrel? What is the effect of a barrel on it's accuracy as it gets hotter and hotter? do you let it cool down periodically?

Just curious if that's a concern or issue or does it not matter as much as I think it does.
I was genuinely curious on people's thoughts on barrel warming (and fouling) as the test shots progress.

I am not an expert - just asking what's either a really dumb question or maybe there us a procedure (if thus is a factor) to avoid or normalise variable throughout the range of shots?

I do know, without a doubt, both of my Weatherby rifles ( a 257 and a 300 ) distinctly produce different results with a warm barrel and a little fouling. Enough that what I'm see on these ladder tests would render the results less useful.

My other guns don't seem to be "as sensitive" to these changes in temps and/or condition of fouling in the barrel (at least not from I can see).

Maybe this is more prevalent on the spaghetti thin barrels shooting high pressure, high velocity loads like the Wby?

Just seeking expert or experienced opinions ...
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  #36  
Old 10-29-2017, 11:28 AM
elkhunter11 elkhunter11 is offline
 
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Originally Posted by EZM View Post
I was genuinely curious on people's thoughts on barrel warming (and fouling) as the test shots progress.

I am not an expert - just asking what's either a really dumb question or maybe there us a procedure (if thus is a factor) to avoid or normalise variable throughout the range of shots?

I do know, without a doubt, both of my Weatherby rifles ( a 257 and a 300 ) distinctly produce different results with a warm barrel and a little fouling. Enough that what I'm see on these ladder tests would render the results less useful.

My other guns don't seem to be "as sensitive" to these changes in temps and/or condition of fouling in the barrel (at least not from I can see).

Maybe this is more prevalent on the spaghetti thin barrels shooting high pressure, high velocity loads like the Wby?

Just seeking expert or experienced opinions ...
I find that properly bedded actions, with floated barrels, seem to be less effected by barrel heat. I also find the better quality barrels, especially lapped barrels, to foul less, and to be less sensitive to fouling.
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  #37  
Old 10-29-2017, 11:46 AM
lclund1946 lclund1946 is offline
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Originally Posted by qwert View Post
Thank you for drawing attention to the key word “begin” in my post # 28, and support for my suspicion of common confusion regarding methods, procedures and terminology for load development. IMHO, there is a definite need for group testing during load development, I just do not start there.

I share your preference for initial testing using single shot / increment ladder procedure.
This does require consistent loading & shooting skills, (which are most often developed by shooting lots of groups).
I note that you report using ~.5% powder charge increments, but no reported target distance/range, (I suspect 100yds).
IMHE, I find Audette ladders shot @ >300yds to be easier to interpret, and certainly more illustrative of barrel harmonics.

I try to obtain the maximum usable information from each shot, and submit this provides the most cost&effort / benefit.
IMHE, 15 shot Audette ladder provides much more information than 3x5 or 5x3 groups, and a full 15 group series will require 45-75 shots.

I am curious how you measure your reported .0025” of primer flow?
and also of your use of PRE (pressure ring expansion) and CHE (case head expansion)?
I note that PRE & CHE are somewhat controversial
https://www.shootingsoftware.com/ftp...%2019%2004.pdf
and would appreciate your opinion and measured experience.

and also how you manage and store the large volume of measured data that you collect?

Good Luck, YMMV.
I began doing load development by using the incremental 5 shot group method as I had been led to believe that 3 shot groups were not adequate. Once I realized that this was more to prove that my rifle did not change POI due to problems not related to accuracy of the load I began using 3 shot groups. This lent itself to the Newberry OCW which I used for a while until I realized that my best groups were usually the next increment above the group that my Chrony showed with the lowest ES &SD. It was also indicating that these increments usually followed an incremental velocity spike which corresponded to a pressure Spike/increment followed by a leveling off of velocity/pressure. I went to using what I call a "Pressure Ladder" using one shot per increment, initially to determine safe pressures in my wildcat cartridges without having to pull a lot bullets if I went overboard, and found that these pressure/velocity spikes were shown on the target. In the leveling off of pressure, after a spike, bullets would clump together and invariably I would find a very stable load in this node especially if the node showed over more than 2 incremental powder increases.

I have developed many good stable loads with this method and find that they shoot well in all rifles regardless of barrel configuration. This has led me to be a bit skeptical about the importance of barrel harmonics. As well every "Good Load", developed at 100 yards, has shot good at longer ranges with little vertical.

I used 0.1 grain increments in my 20 EXTREME as it runs less that 23 grains of powder. If I am doing a Pressure Ladder for larger cases I increase that and go to about 3 grains for 308 size cases and 5 grains for larger cases. Once I find a potential good node I may do groups in 1-2 grain increments in larger cases to find the sweet spot. Playing with seating depth would be the last step if fine tuning is required.

I did buy into the CHE method as it was reported in some reloading manuals that did not show actual pressures. However since some manuals have begun listing actual pressures I have come to realize that any CHE exceeds the pressures that the case was designed for. I do use PRE, measured to 0.0001", and find it very accurate in determining pressure increases and remaining within the pressure limits of a particular case. Since doing this I have learned to use factory rounds as benchmarks to what pressures they are running. I have also learned that virtually all factory rounds do not fire form brass past the Saami Maximimum Cartridge dimensions at the Base Datum (Pressure ring). In fact some do not reach pressures that distort the new brass at all in this area much like my lower pressures loads in the 20 EXTREME. I hope to do a report on my findings with about a dozen different 223, once fire brass, brass Reformed to 20-223 EXTREME and include some new Lapua and Winchester brass results. It was indeed an eye opener.

With many of the loads I develop I find that primer flow around the firing pin is the first indicator that I am nearing Max Pressure. To measure this I use my calipers and zero them on the length of a fired case. I then punch the primer and measure the difference which is primer flow. In my 20 EXTREME there is Zero primer flow with 39/40 grain bullets running at 3500 fps with my low pressure gopher loads. Push them up to 3650 and I get measurable PRE and primer flow which I like to keep at less than 0.003" which is less than some factory rounds in 223 and 204R. Primer flow can reach as much as 0.008", without piercing, but there will be CHE and perhaps even blown primers at these pressures if the bolt does not get sticky.

I do not have a great system for record keeping like you obviously do as I am not that great on a computer and getting too feeble minded to learn. The graph that tasco posted is very good at illustrating the results of a Pressure Ladder and hope that he keeps up the good work.
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  #38  
Old 10-29-2017, 11:52 AM
qwert qwert is offline
 
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Originally Posted by EZM View Post
snip
maybe there us a procedure (if thus is a factor) to avoid or normalise variable throughout the range of shots?
Group targets can be shot in 'round robin' procedure.

- fire fouling shots as needed after cleaning.

- fire 1st shot from 1st increment on target 1
- fire 1st shot from 2nd increment on target 2
- fire 1st shot from 3rd increment on target 3
repeat to final increment then
- fire 2nd shot from 1st increment on target 1
- fire 2nd shot from 2nd increment on target 2
- etc etc

- number targets and enter all data in permanent record log for future analysis.

This system allows testing to stop when results become obvious.
Fire 3-4 shots at all targets, then finish only promising groups with additional shots to confirm initial results.

Good Luck, YMMV
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  #39  
Old 10-29-2017, 12:02 PM
qwert qwert is offline
 
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Originally Posted by lclund1946 View Post
I began doing load development by using the incremental 5 shot group method as I had been led to believe that 3 shot groups were not adequate. Once I realized that this was more to prove that my rifle did not change POI due to problems not related to accuracy of the load I began using 3 shot groups. This lent itself to the Newberry OCW which I used for a while until I realized that my best groups were usually the next increment above the group that my Chrony showed with the lowest ES &SD. It was also indicating that these increments usually followed an incremental velocity spike which corresponded to a pressure Spike/increment followed by a leveling off of velocity/pressure. I went to using what I call a "Pressure Ladder" using one shot per increment, initially to determine safe pressures in my wildcat cartridges without having to pull a lot bullets if I went overboard, and found that these pressure/velocity spikes were shown on the target. In the leveling off of pressure, after a spike, bullets would clump together and invariably I would find a very stable load in this node especially if the node showed over more than 2 incremental powder increases.

I have developed many good stable loads with this method and find that they shoot well in all rifles regardless of barrel configuration. This has led me to be a bit skeptical about the importance of barrel harmonics. As well every "Good Load", developed at 100 yards, has shot good at longer ranges with little vertical.

I used 0.1 grain increments in my 20 EXTREME as it runs less that 23 grains of powder. If I am doing a Pressure Ladder for larger cases I increase that and go to about 3 grains for 308 size cases and 5 grains for larger cases. Once I find a potential good node I may do groups in 1-2 grain increments in larger cases to find the sweet spot. Playing with seating depth would be the last step if fine tuning is required.

I did buy into the CHE method as it was reported in some reloading manuals that did not show actual pressures. However since some manuals have begun listing actual pressures I have come to realize that any CHE exceeds the pressures that the case was designed for. I do use PRE, measured to 0.0001", and find it very accurate in determining pressure increases and remaining within the pressure limits of a particular case. Since doing this I have learned to use factory rounds as benchmarks to what pressures they are running. I have also learned that virtually all factory rounds do not fire form brass past the Saami Maximimum Cartridge dimensions at the Base Datum (Pressure ring). In fact some do not reach pressures that distort the new brass at all in this area much like my lower pressures loads in the 20 EXTREME. I hope to do a report on my findings with about a dozen different 223, once fire brass, brass Reformed to 20-223 EXTREME and include some new Lapua and Winchester brass results. It was indeed an eye opener.

With many of the loads I develop I find that primer flow around the firing pin is the first indicator that I am nearing Max Pressure. To measure this I use my calipers and zero them on the length of a fired case. I then punch the primer and measure the difference which is primer flow. In my 20 EXTREME there is Zero primer flow with 39/40 grain bullets running at 3500 fps with my low pressure gopher loads. Push them up to 3650 and I get measurable PRE and primer flow which I like to keep at less than 0.003" which is less than some factory rounds in 223 and 204R. Primer flow can reach as much as 0.008", without piercing, but there will be CHE and perhaps even blown primers at these pressures if the bolt does not get sticky.

I do not have a great system for record keeping like you obviously do as I am not that great on a computer and getting too feeble minded to learn. The graph that tasco posted is very good at illustrating the results of a Pressure Ladder and hope that he keeps up the good work.
Thanks for this detailed report, I am very impressed by your attention to objective details.
I well reply further after reflection.

Good Luck, YMMV.
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  #40  
Old 10-29-2017, 12:31 PM
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EZM EZM is offline
 
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Originally Posted by qwert View Post
Group targets can be shot in 'round robin' procedure.

- fire fouling shots as needed after cleaning.

- fire 1st shot from 1st increment on target 1
- fire 1st shot from 2nd increment on target 2
- fire 1st shot from 3rd increment on target 3
repeat to final increment then
- fire 2nd shot from 1st increment on target 1
- fire 2nd shot from 2nd increment on target 2
- etc etc

- number targets and enter all data in permanent record log for future analysis.

This system allows testing to stop when results become obvious.
Fire 3-4 shots at all targets, then finish only promising groups with additional shots to confirm initial results.

Good Luck, YMMV
Excellent response, exactly what I was looking for. I was just thinking of doing the same thing, but since I have zero experience going through the "entire" ladder process, I wanted to ensure my thoughts made sense.

I have usually loaded up a few (usually 4 loads) different recipes (like 5 rounds of each) and went off to the range to see which ones grouped best.

I typically had a target set up for each load, and rotated them just like you indicated.

That way I shot 20 times and got to see which one of the 4 loads was best for the rifle and left it at that.

I am curious about beginning a process to build a gun from scratch, hand load and try seeing what level of accuracy I can get out of it. It sounds like it would be a fun way to spend some time and take what little I know and try and apply myself. A new hobby to occupy some time.

I just gotta figure out what cartridge, what action, etc... and likely go start messing around from there. The forum is probably a good place to benefit from the experience of a few guys that can teach me something.
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  #41  
Old 10-29-2017, 12:47 PM
HW223 HW223 is offline
 
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With many of the loads I develop I find that primer flow around the firing pin is the first indicator that I am nearing Max Pressure. To measure this I use my calipers and zero them on the length of a fired case. I then punch the primer and measure the difference which is primer flow. In my 20 EXTREME there is Zero primer flow with 39/40 grain bullets running at 3500 fps with my low pressure gopher loads. Push them up to 3650 and I get measurable PRE and primer flow which I like to keep at less than 0.003" which is less than some factory rounds in 223 and 204R. Primer flow can reach as much as 0.008", without piercing, but there will be CHE and perhaps even blown primers at these pressures if the bolt does not get sticky.
Primer flow is not necessarily a function of pressure,it is usually more related to mechanics of your particular bolt and chamber set up , pm me and I can explain , we run over 70,000 and have no measurable primer flow or signs of over pressure . All has to do with proper and exact fit of brass , dies and chamber
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  #42  
Old 10-29-2017, 12:47 PM
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Jay Kyle Jay Kyle is offline
 
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Method 1 vs Method 2 vs yada-yada

There are multiple ways to iterate load development - BUT there certain factors that are common across the various methods:

1. Identify and control your variables - First and foremost!! - Understand *ALL* factors that go into making that accurate and repeatable shot. Know which are limiting, which are independent, which are dependent - or worse yet, which are interdependent. For example - you find your accuracy node - but then adjust your seating depth - now are you still at you accuracy node for that new depth? (BTW Here it's good to write out all factors that come into play.)

2. Solid Test Method - Select a testing Method that covers the material combinations of your variables. This is where folks get tangled up - which method is better or more efficient, etc. - efficiency is nice, but more important, does it cover the material combinations of your variables. (BTW Knowing what's material is where you need to keep an open mind).

2. Attention to detail - be precise in your measurements, know how good your hold is (in MOA or Mill) - uncertainty stacking will drive you crazy

3. Meticulous record keeping - once you've gathered your data, analysis takes some thinking time to reflect and look for subtle information. Since we don't own supercomputers and have mass amounts of data, we can't fall back to machine learning technique's so we have to use the ol'e noggin to distill out the gems.

4. Repeat-ability - Can we repeat or understand the change to results in the face of changing variables.

5. Accept the results - it may be the best your rifle can do! It's too easy to spend the whole life of the barrel looking for the ultimate load.

Pick a good iteration plan - whether that be the Audette, OCW, any of the modified ladder methods, etc. - the key to what your looking for is a method contains the above characteristics (and perhaps a few I might have missed).

Thankfully today we have good tools like Quickload, and lots of other users experience to help us trim out variable combinations that are not material.

Jay

Last edited by Jay Kyle; 10-29-2017 at 01:05 PM. Reason: spelling
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  #43  
Old 10-29-2017, 01:34 PM
Don_Parsons Don_Parsons is offline
 
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^^^ awesome ideas that I'm going to try as well.

Like I mentioned, I ain't no pro at this since its a opened mined to learn and see better ways at tuning these loads to barrels.

Don
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  #44  
Old 10-29-2017, 03:27 PM
lclund1946 lclund1946 is offline
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Originally Posted by HW223 View Post
With many of the loads I develop I find that primer flow around the firing pin is the first indicator that I am nearing Max Pressure. To measure this I use my calipers and zero them on the length of a fired case. I then punch the primer and measure the difference which is primer flow. In my 20 EXTREME there is Zero primer flow with 39/40 grain bullets running at 3500 fps with my low pressure gopher loads. Push them up to 3650 and I get measurable PRE and primer flow which I like to keep at less than 0.003" which is less than some factory rounds in 223 and 204R. Primer flow can reach as much as 0.008", without piercing, but there will be CHE and perhaps even blown primers at these pressures if the bolt does not get sticky.
Primer flow is not necessarily a function of pressure,it is usually more related to mechanics of your particular bolt and chamber set up , pm me and I can explain , we run over 70,000 and have no measurable primer flow or signs of over pressure . All has to do with proper and exact fit of brass , dies and chamber
Primer flow will be worse in a rifle with a loose fitting firing pin or loose fitting brass, as you describe, however it is a function of pressure and will grow with each incremental increase in pressure once started. No doubt some cartridges, or even different loads in some cartridges, will produce more pressure on the primers than others and some primers take more pressure than others. I would like to know which cartridge you are running to 70,000PSI and how you are measuring that pressure. The reason that I ask is that the Ramshot Manual show a Compressed Load of 27.7 grains of LT32 pushing a 68grain FB bullet to 3130 generating only 57,896 PSI in a 6mmPPC.

My 20 Extreme runs very close tolerances as I can size with ZERO HS (usually 0.005"), 0.001" clearance at the shoulder and the same at the base datum. Primer flow in my CZ 527 does not look as ugly as it does in a Remington but it is still there after about 58,000 PSI.

The following chart, perhaps what qwert was wondering about, show the results of measurements taken while doing a Pressure Ladder test in a 20 EXTREME LB chamber which was 0.001" larger at the base datum than my 20 EXTREME. It clearly shows incremental pressure increases by Primer flow (protrusion) and corresponding base expansion. Springback is actually brass/ chamber clearance at the Chamber Base Datum and is usually 0.001" less in a standard EXTREME Chamber. You will note that the pressure spike at shot #5 was indicated by the chronograph as well as the PRE and primer flow and remained stable to the pressure increase at shot #9 where I stopped primarily due to the primer flow that was about to go up over 0.0025" where I like to call max even though the case could have taken more.

[IMG][/IMG]

Subsequent 5 shot targets (3) showed 20.8 grains of H 322 right on target with a 0.54" group. This summer I tested this load in my new 24" Benchmark barrel installed on my original CZ 527 in 20 EXTREME. It was a Calm day at 24Celsius and this load shot right on target and placed 5 shots into 0.32". The Lab Radar clocked it at 3509 fps and while the Winchester brass grew 0.0005" at the base datum (PRE) the primers did not have measurable flow. I had the same results with AA 2015 at 21.3 grains which was a near full case only the 3541 MV showed slightly higher pressure as the primer flow measured .0015".
I would post targets but PhotoBucket is not uploading??
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  #45  
Old 10-29-2017, 07:51 PM
Don_Parsons Don_Parsons is offline
 
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Originally Posted by James 1 View Post
When developing rounds this way. What is your experience with how the rifles perform when complete?
When I put together a load that has not been tested, it shoots ok groups out to 400 to 500M. At 600 and beyond, I start to see the 10 shoot groups opening up.
The first 2 times going to the 1 km range the bullets were all over the place. 24" spread give or take.

I knew something wasn't working,,, a heavy barrel rifle is normally pretty consistant, a full rifle inspection followed as I made sure the action was seated in the stock with proper torque on the bolts and bases, rings, scope.
Everything checked out and the next 1 km shoot wasn't any better.

After chatting with Franklin at the RMH Range,,, he asked if I did a ladder test.

This was the first time I really thought about buckling down to try a proper ladder.
What a disaster that was.

I shot lots of bullets with .5gr increases at 1 target.
After 50 shots at 100 meters, the target looked like a useless peace of paper with holes every where.

I Drew circles, boxes, triangles, octagons, and all kinds of patterns to distinguish the difference between the groups.

LOL. Total waist of time, nothing close to a ladder, just a big jumbo of nothing.

As I posted above, after trying the 3 shots,,, one at each target I started to at least see some signs of a so called ladder.
All 3 targets had bullet holes from 47.5gr to 57gr's doing the .5gr incress in powder charge.

Those three targets at 100 meters were easier to read, when the first 300M test happened,,, that's when I could really start to see the spread between the ladder rungs. Some were spread out, some were tight.

The best ladder happened at 600 meters on that calm day of no winds.

The minimum powder charge of 47.5gr's of H 4831 started things off.
48gr to 48.5gr, then 49gr as the bullets kept climbing.
50gr, 50.5gr, 51gr, 51.5 were grouped close.
Things started climbing from 52gr, 52.5, 53, 53.5, and 54 grains.
54.5gr, 55gr, 55.5gr were grouped tight with very little rise. ((( A guess only that this seemed to be the top Node.))) As I explain later.

The 30/06 charge was getting close to the max with that powder.
The ladder started to spread at 56,gr 56.5gr and 57gr.
57.5gr showed a bit of stiff bolt handle lift. 58gr was hot.
Super compressed powder charge,,, tall funnel to get the powder down into the case so I could seat the bullet.


Harvest season was closing in, the lower 50gr to 51.5gr load was working, but there was lots of bullet drop happening.
I knew I was onto something in the 54.5gr to 55.5gr category.

So I did the .3 grain node test from 54.5gr, 54.7gr, 55gr, 55.3gr, 55.6gr, 55.9gr, and 56.2 as the ladder started to climb. 600 meters as normal.

I shot 2 more test groups to settle on the 55.3gr for this powder, primer, case, and bullets of the same lot numbers.

I'm not good at long range shooting, nor will I ever be able to pull this off any time soon with a heavy barrel hunting rifle.

The day was calm with no winds, the best of light conditions, solid rest in the pron shooting format using the Remple F Class bypod rest, and 25 X zoom.

I was lucky, I mean lucky to pull off a 9" by 12" wide Five shot group at the 1 km mark.

I followed up with 2 more groups all with in a 12" group.
Lucky is a under statement.

This put total confidence in me, the rifle, and ammo for this harvest season.

I don't know if doing this ladder test helped, I only hope that it has.
Purhaps I can fine tune more from this point. I had to buckle down to do this, it was no walk in the park. I'm putting it all on the line here.
The most unlikely candidate of non-achievements, and this I share openly.

This is purhaps why this thread got underway.

Sorry to all for the long post, but I'm trying my best to express what has worked up to this point and hope to gain more info as I move forward on better / wizer load development.

PS:
Don't think for one second that I went out and started hitting the 1 km target just like that.
It took me many bullets and 100's of trips back and forth to slowly work my distance over the day.

1700+ rounds this year out of this rifle to get close to where its at, I only hope that I can do this same thing with my soon to be new rifle with 100 to 200 shots.

I hope for that is

Don

Last edited by Don_Parsons; 10-29-2017 at 08:09 PM.
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  #46  
Old 10-29-2017, 11:24 PM
HW223 HW223 is offline
 
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Originally Posted by lclund1946 View Post
Primer flow will be worse in a rifle with a loose fitting firing pin or loose fitting brass, as you describe, however it is a function of pressure and will grow with each incremental increase in pressure once started. No doubt some cartridges, or even different loads in some cartridges, will produce more pressure on the primers than others and some primers take more pressure than others. I would like to know which cartridge you are running to 70,000PSI and how you are measuring that pressure. The reason that I ask is that the Ramshot Manual show a Compressed Load of 27.7 grains of LT32 pushing a 68grain FB bullet to 3130 generating only 57,896 PSI in a 6mmPPC.

My 20 Extreme runs very close tolerances as I can size with ZERO HS (usually 0.005"), 0.001" clearance at the shoulder and the same at the base datum. Primer flow in my CZ 527 does not look as ugly as it does in a Remington but it is still there after about 58,000 PSI.

The following chart, perhaps what qwert was wondering about, show the results of measurements taken while doing a Pressure Ladder test in a 20 EXTREME LB chamber which was 0.001" larger at the base datum than my 20 EXTREME. It clearly shows incremental pressure increases by Primer flow (protrusion) and corresponding base expansion. Springback is actually brass/ chamber clearance at the Chamber Base Datum and is usually 0.001" less in a standard EXTREME Chamber. You will note that the pressure spike at shot #5 was indicated by the chronograph as well as the PRE and primer flow and remained stable to the pressure increase at shot #9 where I stopped primarily due to the primer flow that was about to go up over 0.0025" where I like to call max even though the case could have taken more.

[IMG][/IMG]

Subsequent 5 shot targets (3) showed 20.8 grains of H 322 right on target with a 0.54" group. This summer I tested this load in my new 24" Benchmark barrel installed on my original CZ 527 in 20 EXTREME. It was a Calm day at 24Celsius and this load shot right on target and placed 5 shots into 0.32". The Lab Radar clocked it at 3509 fps and while the Winchester brass grew 0.0005" at the base datum (PRE) the primers did not have measurable flow. I had the same results with AA 2015 at 21.3 grains which was a near full case only the 3541 MV showed slightly higher pressure as the primer flow measured .0015".
I would post targets but PhotoBucket is not uploading??
6PPC with lt32 27.7 = 58.000 , I have run up to 29.6-29.9 with no primer flow and no "hard bolt lift " what's the pressure ?
N133 book says max load compressed 28.2 ,we regularly run 29.9-30.6 which will drive a 68 gr up to 3650 fps on lab radar depending on the day federal primers which are the weaker cups ,again no primer flow and no hard bolt lift . Hard bolt lift in my experience comes from a couple of things , unsquare bolt face and related components ,chamber and sizing die differences ,and an out of tune rifle , but thats a whole other discussion
I have gone as high as 31.6 with n133 , again no hard bolt lift and no primer flow , also no gain in accuracy
Primer pressure flow is usually caused by a few things , if they are not correct you will see primer flow even at lower pressures and you can blank a primer if you keep going , looks like you have found a way to manage pressure on "your fire control"and that's good , all should do the same ,it just doesn't even necessarily translate to all rifles
Hope that helps
What you see on your groups and subsequent analyses is quite different from what I see
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Old 10-30-2017, 06:45 AM
elkhunter11 elkhunter11 is offline
 
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6PPC with lt32 27.7 = 58.000 , I have run up to 29.6-29.9 with no primer flow and no "hard bolt lift " what's the pressure ?
N133 book says max load compressed 28.2 ,we regularly run 29.9-30.6 which will drive a 68 gr up to 3650 fps on lab radar depending on the day federal primers which are the weaker cups ,again no primer flow and no hard bolt lift . Hard bolt lift in my experience comes from a couple of things , unsquare bolt face and related components ,chamber and sizing die differences ,and an out of tune rifle , but thats a whole other discussion
I have gone as high as 31.6 with n133 , again no hard bolt lift and no primer flow , also no gain in accuracy
Primer pressure flow is usually caused by a few things , if they are not correct you will see primer flow even at lower pressures and you can blank a primer if you keep going , looks like you have found a way to manage pressure on "your fire control"and that's good , all should do the same ,it just doesn't even necessarily translate to all rifles
Hope that helps
What you see on your groups and subsequent analyses is quite different from what I see
I agree, with a true action and close tolerances on the firing pin/ bolt face, you can develop more velocity without seeing certain pressure signs. That doesn't mean that there is less pressure, it just means that you can't depend on primer flow or resistance on bolt lift to see it before it is well above the accepted pressure level for the cartridge. As well , calculations such as Quickload are not an exact science, because contrary to what some people believe, not all chambers are cut to SAAMI standards, not all people seat bullets to the standard SAAMI COL, and not all components are exactly the same. A person can depend far too much on SAAMI cartridge drawings or on calculations, to predict what you think should be happening in your rifle, or you can look at the results of the load being fired in your rifle to get a better idea of what is actually happening.
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Old 10-30-2017, 07:14 AM
Don_Parsons Don_Parsons is offline
 
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^^^ the above info of stiff bolt handle lift could be correct.

Purhaps doing a custom fitted precision bolt with small primer hole and tool gaged bolt on top of lug lapping "might address some of this, as mentioned,,, purhaps another thread. But it is something to consider for sure.

I come from the harvest and plinking world, so reaching out past my normal comfort zone gets me thinking.

I will soon see the difference between a custom built heavy weight harvest rifle and a custom precision match rifle built for long range shooting,,, "targets only that is."

My good 2 long time close friends from our area will be accompanying me this year,,, one is well placed in the world national level, the other is the hands of glass.

Hopefully between all 3 of us we will be able to push this rifle to its limits.

I like what my other friend said when attending the first long range shoot I'd ever seen.

If the rifle, chosen cartrage that are both tuned for competition,,, then the only out lying factor left to sort is our selves.

Address the first 2 variables, then buckle down on us the shooter.

The match rifle thing is sorted, cartrage, powder, primer, bullet as well.

So fine tuning the ammo and dialing in my skills "could" take some time.

I only hope that I'm getting it right.

Thanks to everyone for sharing, the above info sheds some light on areas to consider.

When I seen the pictures of a long distant group shot at 600 meters by one of our members from a hunting rifle, I was hooked.

Lots of bullets out of my harvest/ heavy weight rifle this year as I attempt to close in on his precision group.

Don
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  #49  
Old 10-30-2017, 10:58 AM
6.5x47 lapua 6.5x47 lapua is offline
 
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That's pretty obvious. But, that doesn't stop Don from typing
Don is one of the few people in this world who is honest and forthright about everything and a true student of the world. He is just sharing his experiences with like minded people.i only commented because some of what he is doing is counterproductive to true long range competition accuracy.
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Old 10-30-2017, 11:41 AM
Salavee Salavee is offline
 
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Originally Posted by elkhunter11 View Post
I agree, with a true action and close tolerances on the firing pin/ bolt face, you can develop more velocity without seeing certain pressure signs. That doesn't mean that there is less pressure, it just means that you can't depend on primer flow or resistance on bolt lift to see it before it is well above the accepted pressure level for the cartridge. As well , calculations such as Quickload are not an exact science, because contrary to what some people believe, not all chambers are cut to SAAMI standards, not all people seat bullets to the standard SAAMI COL, and not all components are exactly the same. A person can depend far too much on SAAMI cartridge drawings or on calculations, to predict what you think should be happening in your rifle, or you can look at the results of the load being fired in your rifle to get a better idea of what is actually happening.
Quickload may not be exact, but it is software that will reliably predict loads for any cartridge/chamber/barrel combinations ...if it is used correctly. Data presented by Quickload for any cartridge load combination will be erroneous if the inputs are not correct for that particular load..

First of all, a Chronograph is necessary.
Secondly, Chronograph results from a particular load must be must be documented.
Next, burn rates for a particular powder/primer/temp combination have to be adjusted to coincide with chronograph results. Powder burn rates apply to one particular load combination .. only.

Failure do make these basic adjustments to the QL software will amount to nothing less than a very rough estimate .. often not a good one.
Correct inputs will put you "on the money" very consistently.
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Old 10-30-2017, 01:52 PM
6.5x47 lapua 6.5x47 lapua is offline
 
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Originally Posted by lclund1946 View Post
The thread is about finding an accurate load. While many different approaches can be used the Audettet ladder test has been adopted by some. While I have used it I find that doing a pressure ladder using a single shot at each increment, as I have shown, works best for me. I have worked up a number of loads that shoot sub 1/2 MOA, mostly in wildcat cartridges that I have designed that have no manuals to follow, and do not run pressures that cause sticky bolt or blown primers.

It does not matter what discipline you shoot it is a fact that a load that will consistently shoot Sub 1/2 Moa groups will do better than one that won't do 1MOA groups. Combine that with a stable load, that consistently shoots a low Extreme Spread, especially if the Standard Deviation is in the single digits will do well at longer distances. Once a good load is established then it has to be tested to the maximum range it is going to be used to ensure that it remains stable. I have never had a good load, developed in this manner, that failed to perform at ranges that they were designed for. As well a good load will shoot well in most any rifle and I have many ladder targets, and follow up groups to illustrate that.

That being said I would be interested in finding out how you find a good load, especially for long range, without being able to shoot good groups at closer ranges.
It’s pointless for me to argue with you on this so I will leave you with the fact that positive compensation comes into play with barrels and nodes. This changes everything you have known in your extensive loading experience.
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Old 10-30-2017, 02:09 PM
Ryan.M.Anderson Ryan.M.Anderson is offline
 
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There is a big thread over on CGN that argues about load development for a few pages.

Jerry Teo (Canadian F-Classer) swears up and down that ES/SD numbers don't matter (I am paraphrasing for simplicity) and also references the positive compensation thing. BTW, the first thing that shows up when you google positive compensation is a forum where the merits of it are debated. Jerry says he does his load development based on results on target. As he does 1,000 F-class he will test at 1,000.

I do not have access to a 1,000 yard range. I do my load development at 100M with a chrony beside me. I find the load that groups the best and has good ES/SD numbers and go from there. Normally, there is a strong correlation between the 2 but not always. When I did my 6.5X47 development I had a load that had super low SD/ES (2 & 5 respectively) but would not group. I had to choose a load with slightly worse SD/ES but a much better grouping. I normally follow this up by validating at distance when I get the chance.

I should note that I don't develop loads to get 1/10th minute groups. Once I hit 1/2 minute I call it a day. I do not need more than that personally. My loads probably wouldn't win BR or F-Class matches.

I think there are many ways to get the job done.
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Old 10-30-2017, 08:50 PM
6.5x47 lapua 6.5x47 lapua is offline
 
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Originally Posted by Ryan.M.Anderson View Post
There is a big thread over on CGN that argues about load development for a few pages.

Jerry Teo (Canadian F-Classer) swears up and down that ES/SD numbers don't matter (I am paraphrasing for simplicity) and also references the positive compensation thing. BTW, the first thing that shows up when you google positive compensation is a forum where the merits of it are debated. Jerry says he does his load development based on results on target. As he does 1,000 F-class he will test at 1,000.

I do not have access to a 1,000 yard range. I do my load development at 100M with a chrony beside me. I find the load that groups the best and has good ES/SD numbers and go from there. Normally, there is a strong correlation between the 2 but not always. When I did my 6.5X47 development I had a load that had super low SD/ES (2 & 5 respectively) but would not group. I had to choose a load with slightly worse SD/ES but a much better grouping. I normally follow this up by validating at distance when I get the chance.

I should note that I don't develop loads to get 1/10th minute groups. Once I hit 1/2 minute I call it a day. I do not need more than that personally. My loads probably wouldn't win BR or F-Class matches.

I think there are many ways to get the job done.
everyone struggles with the competitive long range concept of vertical testing through positive compensation versus group shooting.there are also many more factors to correcting vertical than just doing multiple powders in .3 grain increments. it really sucks when you go through all of the effort shooting groups at 100 meters to find out your rifle is negatively tuned for long distance and shoots like crap.this is why i post this stuff because this concept is very foreign but very essential to long range shooting;especially for guys like Don who are going to shoot competitively.
it is nice to be able to test at 1000 if that is the distance youplan on shooting to but the testing can be done at much shorter distances quite successfully if you use the proper format.
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  #54  
Old 10-31-2017, 01:51 PM
lclund1946 lclund1946 is offline
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Originally Posted by 6.5x47 lapua View Post
It’s pointless for me to argue with you on this so I will leave you with the fact that positive compensation comes into play with barrels and nodes. This changes everything you have known in your extensive loading experience.
I am not looking for an argument but was wondering what you do differently and I guess positive compensation is it. I did a bit of research and all I could seem to find is that a properly tuned barrel should produce round groups at closer range which would compensate for vertical dispersion in bullets with different muzzle velocities? I believe a round group is one that is as wide as it is high?? I would imagine a 1/3 Diameter group would be preferred over one with a 1" diameter at 100 yards???

Looking at virtually all of the many good groups that I have developed they all seem to produce round groups at under 1/2". I did wonder why they seldom had the lowest ES and SD or even had seemingly high ES and still grouped great at 300 to 600 yards which is the farthest that I have shot as I shoot gophers and moose and have never had the equipment to go further. Could it be that my method of load development results in a tuned barrel much the same as positive compensation or do you use mechanical devices like the barrel tuners that were mounted on some factory rifles?

The Pressure ladder that I posted had three bullets landing in a round group measuring about 0.06 and the subsequent groups I shot were round with the exception of the flier in Target 4. The next step is to see how they perform at 500 yards/meters which will be to determine if my trajectory and windage estimates need adjustment and if vertical dispersion is a problem.
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Old 10-31-2017, 02:02 PM
elkhunter11 elkhunter11 is offline
 
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Originally Posted by Salavee View Post
Quickload may not be exact, but it is software that will reliably predict loads for any cartridge/chamber/barrel combinations ...if it is used correctly. Data presented by Quickload for any cartridge load combination will be erroneous if the inputs are not correct for that particular load..

First of all, a Chronograph is necessary.
Secondly, Chronograph results from a particular load must be must be documented.
Next, burn rates for a particular powder/primer/temp combination have to be adjusted to coincide with chronograph results. Powder burn rates apply to one particular load combination .. only.

Failure do make these basic adjustments to the QL software will amount to nothing less than a very rough estimate .. often not a good one.
Correct inputs will put you "on the money" very consistently.
If Quickload was so accurate, why do the companies producing ammunition and manuals for reloading bother with specialized equipment to estimate pressure? You can fudge the burn rates for the powder to compensate for differences in velocity, but how do you know that a difference in velocity is caused by a different powder burn rate, rather than a difference in chamber/throat dimensions?
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Old 10-31-2017, 04:11 PM
lclund1946 lclund1946 is offline
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Originally Posted by lclund1946 View Post
Primer flow will be worse in a rifle with a loose fitting firing pin or loose fitting brass, as you describe, however it is a function of pressure and will grow with each incremental increase in pressure once started. No doubt some cartridges, or even different loads in some cartridges, will produce more pressure on the primers than others and some primers take more pressure than others. I would like to know which cartridge you are running to 70,000PSI and how you are measuring that pressure. The reason that I ask is that the Ramshot Manual show a Compressed Load of 27.7 grains of LT32 pushing a 68grain FB bullet to 3130 generating only 57,896 PSI in a 6mmPPC.

My 20 Extreme runs very close tolerances as I can size with ZERO HS (usually 0.005"), 0.001" clearance at the shoulder and the same at the base datum. Primer flow in my CZ 527 does not look as ugly as it does in a Remington but it is still there after about 58,000 PSI.

The following chart, perhaps what qwert was wondering about, show the results of measurements taken while doing a Pressure Ladder test in a 20 EXTREME LB chamber which was 0.001" larger at the base datum than my 20 EXTREME. It clearly shows incremental pressure increases by Primer flow (protrusion) and corresponding base expansion. Springback is actually brass/ chamber clearance at the Chamber Base Datum and is usually 0.001" less in a standard EXTREME Chamber. You will note that the pressure spike at shot #5 was indicated by the chronograph as well as the PRE and primer flow and remained stable to the pressure increase at shot #9 where I stopped primarily due to the primer flow that was about to go up over 0.0025" where I like to call max even though the case could have taken more.

[IMG][/IMG]

Subsequent 5 shot targets (3) showed 20.8 grains of H 322 right on target with a 0.54" group. This summer I tested this load in my new 24" Benchmark barrel installed on my original CZ 527 in 20 EXTREME. It was a Calm day at 24Celsius and this load shot right on target and placed 5 shots into 0.32". The Lab Radar clocked it at 3509 fps and while the Winchester brass grew 0.0005" at the base datum (PRE) the primers did not have measurable flow. I had the same results with AA 2015 at 21.3 grains which was a near full case only the 3541 MV showed slightly higher pressure as the primer flow measured .0015".
I would post targets but PhotoBucket is not uploading??
I agree that PR and primer flow are not always an accurate indicator of high pressure for the reasons mentioned. However they are tools that can be used in conjunction with a chronograph, as I have outlined, to develop safe loads when no data is available. I use drawings to determine how much powder can be seated under the bullet when using different brass and powders and do not use heavily compressed loads or fast burning powders that do not give a good load density. I use Saami drawings to determine the Max Cartridge Dimension at the Base Datum (PRE) and the Minimum and Maximum chamber dimensions that have 0.002" tolerances and of course I use Reamer Dimensions for Wildcats which run +/-0.001" tolerances. Saami Max cartridge diameter runs 0.001" less than Minimum Chamber at the PRE and most cartridges are about 0.003" to 0.006" under maximum which is where most of the initial case stretch happens. Virtually all Factory ammunition that I have measured at the PRE is not fire formed to the max cartridge dimension and will have at least 0.001"- 0.003" clearance from a minimum chamber which corresponds to some FL sizing dies. The 20 EXTREME LB that I used in the chart has about 0.002" clearance with the Winchester Brass so I used 0.0014" chamber clearance (spring back) as max for that brass. If brass is never allowed to stretch past Max Saami specs or 0.0005" as in my wildcat you will not have a pressure problem. Once a good load is developed it can be used as a basis for using other powder, primers or brass. In this case CCI 450 primers are harder than the Rem 7 1/2 primers so may not flow as much. Remington, Norma and Lapua brass are softer and will expand more so I use velocity as the benchmark. Brass formed form Lake city will run much higher pressures without stretching but hold about 0.2 grains more powder so accuracy/velocity become the benchmark.

This chart shows the workup with IMR 8208 running 40 V-Max compared to max loads with Nosler 40 BT and sierra 39 BK. Velocities have been chronographed between 3600 and 3650 which was slower than the estimated 3750 which I thought I had corrected.
[IMG][/IMG]

This chart shows why I stopped at 20.3 grains of RL 10X with the 39 BK where it was running about 3550 fps. Brass showed no pressure signs at 21.7 grains when fired in a cool chamber in the shade. In the hot sun, with a hot chamber, under sustained fire the primer blew with the Chrony registering near 3850 fps when I reached 21.5 grains.
[IMG][/IMG]

It was pretty hard to resist tempting fate when the RL 10X ladder was shot.
[IMG][/IMG]

The 39/40 grain best loads showed very little vertical dispersion when tested at 300 Meters.
[IMG][/IMG]
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  #57  
Old 10-31-2017, 06:26 PM
6.5x47 lapua 6.5x47 lapua is offline
 
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Originally Posted by lclund1946 View Post
I am not looking for an argument but was wondering what you do differently and I guess positive compensation is it. I did a bit of research and all I could seem to find is that a properly tuned barrel should produce round groups at closer range which would compensate for vertical dispersion in bullets with different muzzle velocities? I believe a round group is one that is as wide as it is high?? I would imagine a 1/3 Diameter group would be preferred over one with a 1" diameter at 100 yards???

Looking at virtually all of the many good groups that I have developed they all seem to produce round groups at under 1/2". I did wonder why they seldom had the lowest ES and SD or even had seemingly high ES and still grouped great at 300 to 600 yards which is the farthest that I have shot as I shoot gophers and moose and have never had the equipment to go further. Could it be that my method of load development results in a tuned barrel much the same as positive compensation or do you use mechanical devices like the barrel tuners that were mounted on some factory rifles?

The Pressure ladder that I posted had three bullets landing in a round group measuring about 0.06 and the subsequent groups I shot were round with the exception of the flier in Target 4. The next step is to see how they perform at 500 yards/meters which will be to determine if my trajectory and windage estimates need adjustment and if vertical dispersion is a problem.
you have part of it but you are still thinking in terms of group shooting for long range shooting.whoever wrote positive compensation barrel tuning forms round groups at short distance which benefit long range shooting have no clue about what they are talking about.tuning rifles at distances or for distances requires tuning for the tightest vertical node at distance. most people shooting ladder tests have no idea what they are trying to accomplish in the first place because of all the misleading information circulating on the internet.
having seen,talked with,and shot against most all of the best long range shooters in the world the consensus is the same for tuning to shoot at distance.
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Old 11-01-2017, 10:50 AM
lclund1946 lclund1946 is offline
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Originally Posted by 6.5x47 lapua View Post
you have part of it but you are still thinking in terms of group shooting for long range shooting.whoever wrote positive compensation barrel tuning forms round groups at short distance which benefit long range shooting have no clue about what they are talking about.tuning rifles at distances or for distances requires tuning for the tightest vertical node at distance. most people shooting ladder tests have no idea what they are trying to accomplish in the first place because of all the misleading information circulating on the internet.
having seen,talked with,and shot against most all of the best long range shooters in the world the consensus is the same for tuning to shoot at distance.
I am really not thinking of group shooting for long range shooting. I shoot 100 yard groups to confirm that the nodes, determined by the ladder tests, are going to shoot consistently under 1/2 MOA, at acceptable velocities and preferably with Low ES or SD. I then do what I believe is referred to as a "nodal tune" by going to smaller increments, trying different primers or seating depths.

However I believe that you are leaving the impression that Developing a Good Load, using this method, is not necessary as you can use a mechanical tuner to compensate. For most people developing loads to hunt to 600 yards this is adequate if they test the loads to that distance and find that they hold the 1/2 MOA group. I do believe that most people can learn what they are trying to accomplish if given proper guidance which is why I am posting the way I do it and further discussion is always welcome. If they become accomplished at finding a good load for their rifle and want to get into long range competition they will be ready for positive compensation tuning and may even do quite well going"bare".

I did a little more digging and found this information that suggests Nodal tuning can be quite effective to 500 yards+ especially if a tight group, with low ES is found. It may even be suggesting that it is a necessary first step?? I am learning and thank you for pointing the way.
I need to clarify testing at 500 yards. If you want a positive compensation tune, then you want a load that is sufficient to hold in at 500 yards and not be super tight in elevation terms because this is the approaching a middle distance of trajectory where compensation spreads are going to be greatest if you want the rifle to compensate at long range assuming you can identify the slow shots are going high.

If the group is super tight at 500 it may be compensating at that range and past that you enter a brief area of neutral compensation which drops off with greater elevation impact into negative compensation at long range.

If the tight group at 500 yards is a nodal tune it will remain tight if velocity has consistent low extreme spreads. But you run the risk of falling off the node should the atmosphere vary velocity.

I only use 500 yards to confirm 140 yard testing.

You may identify a starting point with incremental loads over a chronograph, plot these and prospect the flat spots in load development having done a primer test first with a safe pet load.


Here is an example of a load that I worked up in this way for one of my wildcats at 100 yards and the next increment above that opened up a bit.
[IMG][/IMG]

It did well at both 400 &500 Meters, except for horizontal dispersion due to wind. The first shot past 100yards is the one that nearly cut the center of the target and elevation was calculated using my Chrony results and RCBS load Exterior Ballistics Program with Berger's BC entered. The young fellow I sold the rifle and ammo to reported no trouble hitting to 950+ yards and even got a 4 1/"2 X 4 1/2" gong at that distance on the fifth shot. I believe that was with the holdovers I provided for the Zeiss conquest scope and shooting prone from a bipod for the first time. So yes a lot can be done, at 100 yards, to get most anyone started on the path to long range shooting even with a custom hunting rifle..

[IMG][/IMG]

Last edited by lclund1946; 11-01-2017 at 11:16 AM.
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  #59  
Old 11-01-2017, 03:48 PM
HW223 HW223 is offline
 
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[QUOTE=lclund1946;3656397]I agree that PR and primer flow are not always an accurate indicator of high pressure for the reasons mentioned. However they are tools that can be used in conjunction with a chronograph, as I have outlined, to develop safe loads when no data is available. I use drawings to determine how much powder can be seated under the bullet when using different brass and powders and do not use heavily compressed loads or fast burning powders that do not give a good load density. I use Saami drawings to determine the Max Cartridge Dimension at the Base Datum (PRE) and the Minimum and Maximum chamber dimensions that have 0.002" tolerances and of course I use Reamer Dimensions for Wildcats which run +/-0.001" tolerances. Saami Max cartridge diameter runs 0.001" less than Minimum Chamber at the PRE and most cartridges are about 0.003" to 0.006" under maximum which is where most of the initial case stretch happens. Virtually all Factory ammunition that I have measured at the PRE is not fire formed to the max cartridge dimension and will have at least 0.001"- 0.003" clearance from a minimum chamber which corresponds to some FL sizing dies. The 20 EXTREME LB that I used in the chart has about 0.002" clearance with the Winchester Brass so I used 0.0014" chamber clearance (spring back) as max for that brass. If brass is never allowed to stretch past Max Saami specs or 0.0005" as in my wildcat you will not have a pressure problem. Once a good load is developed it can be used as a basis for using other powder, primers or brass. In this case CCI 450 primers are harder than the Rem 7 1/2 primers so may not flow as much. Remington, Norma and Lapua brass are softer and will expand more so I use velocity as the benchmark. Brass formed form Lake city will run much higher pressures without stretching but hold about 0.2 grains more powder so accuracy/velocity become the benchmark,

Primer flow is not a tuning aid , it is dangerous and indicative of a less than desirable ignition system , if it’s present in any fired cases
it should be rectified by a competent gunsmith ,all that is being accomplishing is finding out how much pressure this particular combination will take before blanking a primer , it has little bearing on a proper functioning fire control set up.
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  #60  
Old 11-01-2017, 04:57 PM
huntingfamily huntingfamily is offline
 
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Default 10 round load development?

Have a read:

http://www.65guys.com/10-round-load-...t-ladder-test/
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