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So whats the real deal with all this ES/SD BS

while I believe that 90% of this sport is the indian not the arrow I have never had a load with high SD/ES shoot well. Of course that is no guarantee that even with a low ES/SD you will shoot a target like Alex did above. Even at short range the low ES/SD loads consistently give the tightest groups. I have always wondered is the barrel harmonics have something to do with that
 
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while I believe that 90% of this sport is the indian not the arrow I have never had a load with high SD/ES shoot well. Of course that is no guarantee that even with a low ES/SD you will shoot a target like Alex did above. Even at short range the low ES/SD loads consistently give the tightest groups. I have always wondered is the barrel harmonics have something to do with that
This was my thinking exactly and why I was chasing numbers all the time and passing over loads that actually shot well but the numbers sucked. This is the exact case right now with my 22-250 shooting bug holes at 200 yards time after time but the ES numbers are in the high teens to low 20's and changing the charge weight will bring the numbers down but then the groups go to shit.
 
If a barrel is tuned to shoot 2" groups at 1000, the group at about 600 will subtend much more than 2/10th MOA vertically. Maximum ordnate happens at 55 to 60 percent of target range. That's where the two trajectories have the greatest vertical separation

Sierra's software easily plots two trajectories for a given bullet at two muzzle velocities to show that.
Does Sierra's program take barrel compensation into play? Matt
 
using a 6.5 140gn Berger VLD with a G1 BC of .6 and a 2600 - 2650 FPS muzzle velocity (50 ES for the math challanged)

at 100 it does not matter unless you are shooting groups in the zeros

with a fixed point of aim at 300 the point of impact is .7 inches lower on the target at 2600 than it would be at 2650

with a fixed point of aim at 500 the point of impact is 2.6 inches lower on the target at 2600 than it would be at 2650

with a fixed point of aim at 1000 the point of impact is 15.8 inches lower on the target at 2600 than it would be at 2650

that is basic physics, depends on target distance and your own expectations/abilities whether it matters

you can run the numbers yourself at http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi if you doubt
I loaded up a test for my hunting gun trying to find a node and see what shot. I fired them at 1000 yards and shot them just like a match. I colored the bullets an shot them round robin. It was a 338 Lapua IMP shooting 300 grain Bergers.

The first load was 103 grains and went 2903 average.
The next load was 104 grains and averaged 2945.
The third load was 105 grains and averaged 2993.
The first load hit about 4 inches low from point of aim. The second load was right at point of aim. The third load was also right at point of aim. Seven of the last 8 went into 4.25 inches and one leaked out to make it 6.25 inches.

While there clearly was an increase of 50 feet per grain of powder, the target didn't really show it, especially with the last two which were 50 fps different. I have done this with other guns and cartridges also. I believe nodes and barrel compensation can change things. It doesn't make sense if looking at ballistic tables and numbers, but I have seen this happen many times. Matt
 
It doesn't make sense if looking at ballistic tables and numbers, but I have seen this happen many times. Matt

I have no clue as to why your results came out the way they did but why do you bother handloading if you believe consistency or lack of consistency has no effect ? I thought that making consistent ammo is the entire goal of handloading, otherwise you might as well go buy white box ammo from Walmart
 
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I have no clue as to why your results came out the way they did but why do you bother handloading if you believe consistency or lack of consistency has no effect ? I thought that making consistent ammo is the entire goal of handloading, otherwise you might as well go buy white box ammo from Walmart

That's kind of a silly question to ask isn't it?

The first part of that he said that 103 grains of powder shot 2903 (40 fps slower then the next) and printed 4" lower than the latter two charges.

That's something a ballistic calculator should tell you.

Now the second part of that was that there was a 50 fps velocity difference between the second two charges. But because of barrel harmonics and some other effects, they hit the same point of impact on the target. That's something a ballistic calculator cannot tell you.

It's not about a lack of consistency. It's about finding where the barrel wants to consistently hit the same place.

Edit: the point is, there are things going on to shoot small that you cant necessarily find in chronograph results
 
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I have no clue as to why your results came out the way they did but why do you bother handloading if you believe consistency or lack of consistency has no effect ? I thought that making consistent ammo is the entire goal of handloading, otherwise you might as well go buy white box ammo from Walmart
Matt, how did you set all of the 1000 yard records you've set shooting Walmart ammo? ? ? If I'd only have known. . .
 
I have no clue as to why your results came out the way they did but why do you bother handloading if you believe consistency or lack of consistency has no effect ? I thought that making consistent ammo is the entire goal of handloading, otherwise you might as well go buy white box ammo from Walmart
I think you just figured out Matt’s secret to setting his 7 Benchrest world records. Give it a try. Lol.

Edit, please take this as pun intended :-)
 
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before you start flaming me Look back through my past posts, I have always stated that the person pulling the trigger more than the ammo he/she is using but threads like this confuse me. So work with me a bit, that is why I read the forum and ask questions.

Either consistent performing ammo matters or it doesn't which is it? Even though I have never set any sort of record and probably never will I will continue to go for the consistency simply becasue I enjoy the prep and reloading process and hopefully one day the wind/mirage reading might click for me. I am serious though, if you don't feel the velocity consistency matter, why do you bother? I am not trying to make anyone mad I am just curious. What matters and what doesn't, I seem to be getting mixed messages here
 
In a perfect world, es of 0 would shoot 1 hole groups at any distance. We dont live in a perfect world.

I dont bother to load perfectly consistent velocity ammo. But I do bother to load as consistent ammo as I can. I dont care how fast or slow or what its spread is going. I care about what it prints on paper. Some friends have chronographed my loads. And some were not tight es and some were close. Both want to print 3" for ten shots at a 1k. And one did. (Had to get someone else to pull the trigger but that's another subject lol) the load that shot 3", when he chronographed it, it had a 24fps es or something very close to that.

Ultimately we are trying to find a load that can tolerate all of OUR hand loading inconsistencies combined, and variances in bullets etc, and stay together as close as they can be. Not to mention were also trying to control small explosions as close as we can. Two bullets that reach the same velocity 15' from the barrel (or at the muzzle for that matter) may not of accelerated at the same rate to get there.

I think if you wanted to find a load strictly on velocity numbers, you would have to track its acceleration/deceleration between a couple points. This would require bullets with perfectly matched bc values, as bullet velocity, bc, and differential winds affect bullet flight/velocity.
 
before you start flaming me Look back through my past posts, I have always stated that the person pulling the trigger more than the ammo he/she is using but threads like this confuse me. So work with me a bit, that is why I read the forum and ask questions.

Either consistent performing ammo matters or it doesn't which is it? Even though I have never set any sort of record and probably never will I will continue to go for the consistency simply becasue I enjoy the prep and reloading process and hopefully one day the wind/mirage reading might click for me. I am serious though, if you don't feel the velocity consistency matter, why do you bother? I am not trying to make anyone mad I am just curious. What matters and what doesn't, I seem to be getting mixed messages here
The point of my post was not about reloading good ammo. I can guarantee mine is loaded to a hundredth in powder. Even though I know I will get flamed, the primers are also within .01. The point of the post was that there are nodes, sometimes big, and chrono info isn't the most important thing for groups.

I had a Dasher that would shoot in the zeros at 100. The ES was never more then 2 or three. When I shot it in a 1000 yard match, the vertical was never less then 10 inches and most times 13 to 16. I wasted half a season trying to get that load to shoot because according to the numbers, it should have had very little vertical. After I changed loads and the ES was around 12 to 15, the gun shot good enough to win. Matt
 
I had a Dasher that would shoot in the zeros at 100. The ES was never more then 2 or three. When I shot it in a 1000 yard match, the vertical was never less then 10 inches and most times 13 to 16. I wasted half a season trying to get that load to shoot because according to the numbers, it should have had very little vertical. After I changed loads and the ES was around 12 to 15, the gun shot good enough to win. Matt

interesting. I am an retired techie so the technical aspect of the sport fascinates me to no end. BTW an ES of 12 is pretty low for me. I try and get below 20 ES and 10 SD but I don't think I have ever managed single digits on the ES.
 
Does Sierra's program take barrel compensation into play? Matt
No, not directly. If the range step increment is set to a few yards and one bullet uses two muzzle velocities for a longer range, the trajectory height difference at 5 yards can be converted to MOA. If .05" above the LOS, that's darned close to the 1 MOA increase in bore axis angle at the muzzle needed to compensate for its slower muzzle velocity. Sierra's Infinity software calculates to two decimal places; nice for fine ballistic details.
 
I believe nodes and barrel compensation can change things. It doesn't make sense if looking at ballistic tables and numbers, but I have seen this happen many times.
Barrel compensation to make slower bullets leave at higher angles has been known and studied since the early 1900's. Barrel tuning weights tune the muzzle axis vibration frequencies to change the angle above LOS bullets leave at. On the upswing near the peak is the best place. Both center and rim fire rifles have them.
 
I have no clue as to why your results came out the way they did but why do you bother handloading if you believe consistency or lack of consistency has no effect ? I thought that making consistent ammo is the entire goal of handloading, otherwise you might as well go buy white box ammo from Walmart


The results came out that way because the second two charges are in a node, and the first charge was under the node. I'm pretty sure Matt would then recommend loading as perfect of ammo as possible, and in the middle of the node as found in his "ladder TEST" he's giving in this example.

Tom
 
There is still more about long range that we don’t know—especially BR—than we do know. The one thing I know for certainty is that best results are obtained when we try to make everything as good as possible, even if someone else thinks we are “over doing” things

If you are able to tune at the distance you compete, then a chrono my be of little benefit. If you have to tune at short range, and compete at long range, a chrono is a very useful tool.

As a rule of thumb when tuning at 100-200 yds, ES inside of 20 fps will not likely matter at 600/1000 yds. However, it is entirely possible that a great looking 100/200 yd group could have an ES of 30-35 fps, and that much ES may very well show up at 600/1000.

So, for those who compete against me and have to tune at short range, I STRONGLY discourage the use of a chronograph...... :D
 

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