Need help with identifying the cause

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Kezh1729

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Hello all, I have a custom built competition rifle in 6mm dasher, I did some load development with it that I was able to consistently produce one single hole in 100m for 5 shots groups (probably 0.1moa?) My sd is somewhere at 2-5fps for 5 shots group. I recently took it out to 1000 yards and my shots were right and left, up and down it was all over the place. Wind is not a factor, because there were literally no wind that day, and my friends were consistent enough that I think its not a major influential factor.
I use berger 109 hybrids and Lapua fireformed brass, my muzzle velocity is 2920fps, target end velocity is about 1585fps so definitely above the transonic zone, I use 26' MTU barrel with 7.5 twist, nothing wrong with twist rate. My bullet runouts are between one thousandth to four thousandth, and I anneal after every firing with the torch and drill method. I do noticed my reloading press is causing inconsistent runouts for both the brass neck and loaded rounds. Would that be the influential factor for inconsistent POI? Or is it the inconsistent annealing method?Please give me some opinions, on the cause.
 
No wind? What did the mirage look like through the scope? Was it dancing from one side to the other or was it in a boil? Or was it a combination of all three? A lot can happen from 900 to 1000 yards, let alone 100 to 1000 yards. Have you checked this load at 500 or 600 yards?
 
shockman said:
How big was 1k group ? can you give it a MOA value
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Not exactly sure, what I know is that I would get a lot of fliers that could be as much as 3,4 moa off the target(target is a 10’ plate) and then the next shot I might be back near the target again.
 
maynard said:
No wind? What did the mirage look like through the scope? Was it dancing from one side to the other or was it in a boil? Or was it a combination of all three? A lot can happen from 900 to 1000 yards, let alone 100 to 1000 yards. Have you checked this load at 500 or 600 yards?
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Ya no wind, I didn’t, I only shot it at 100m prior to the 1000 yards, my friends was consistently hitting the target.
 
Scope parallax can cause that. Can you adjust the scope to be parallax free at that distance? Also check to see if the eye piece lock ring is tight and if it has a front parallax adjustment lock ring is tight. What about mirage?
 
Dwayne Cyr said:
Scope parallax can cause that. Can you adjust the scope to be parallax free at that distance? Also check to see if the eye piece lock ring is tight and if it has a front parallax adjustment lock ring is tight. What about mirage?
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yup, parallax was adjusted correctly, nothing wrong with the scope and mount, mirage was straight up, pretty much no wind, I was wondering if the inconsistent concentricity of the bullet caused the fliers.
 
Not trying to be a #### but, is this the first time shooting at 1000 yards? What the mirage is doing at the target is only part of the picture. What the mirage/wind is doing the first 1/3-1/2 of the distance to the target has a greater effect. A 10" plate is only 1 MOA at 1000 yards, missing the target altogether is really only a 1/2 MOA error from the center of the target. Without a target backer/paper it would be hard to know exactly how far off the missed shot landed. If you have heat coming off the barrel, and the mirage at the target in a boil you are shooting at a target that really isn't where you think it is. The image of the target will be higher than the actual target.
 
1-trident-1 said:
you missed the learning curve between 100 and 1000 meters.
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That is correct!

Two thoughts come to mind. Having great success at short range is no guarantee at long ranges. Rifles have flex and wobble when they fire. The DCRA target shooters would agonize over dropping a point at the shorts, and have everything fall apart at 800, 900 or 1000. The wisdom of the ages was to leave the tubular recievers alone, and switch to a Lee Enfield for the longs. Just something about the barrel flip at that range plopped the bullets right on target. Secondly, not all bullets perform at extremes. The Army chose 168g Sierras in Lapua factory ammo, and tried to duplicate short range accuracy at long range. The groups were pathetic. Why? That bullet was designed to be best at 300m for international competitions. It lost its mojo past 600 and wasn't predictable.
 
Considering I don't know what the weather is like where you're from, I find it extremely hard to believe there is 0 wind at all. Even the tiniest breeze at 1000 can push the bullet one way or the other off the plate.

Another possibility is that your fundamentals need work. You don't see the affect of poor fundamentals at 100 yards but every little thing is amplified 10x at 1000 yards. Say your rifle shoots 1/2MOA all the time, well just by moving to 1000, your group size is now half the target even if you do everything else perfectly.
 
maynard said:
Not trying to be a #### but, is this the first time shooting at 1000 yards? What the mirage is doing at the target is only part of the picture. What the mirage/wind is doing the first 1/3-1/2 of the distance to the target has a greater effect. A 10" plate is only 1 MOA at 1000 yards, missing the target altogether is really only a 1/2 MOA error from the center of the target. Without a target backer/paper it would be hard to know exactly how far off the missed shot landed. If you have heat coming off the barrel, and the mirage at the target in a boil you are shooting at a target that really isn't where you think it is. The image of the target will be higher than the actual target.
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no, I shot in the same place at least 6,7 times, I was bad before, but I usually get about 10-15% hit rate on target, with my 308(going transonic at 1150yards), but my 6mm dasher performed horribly, I thought it could be my fundamentals so I shot my friend's rifle and the shots was right on. I can miss, but not with a 3moa radius, so I think its most likely my reloading procedure that caused the problem.
 
It could be that your barrel just doesn't like the Hybred bullets. They might work great at short range but start to get a little wonky at long range.
At one time I tried the new Barne's Match Burner bullets, 100 yard results were not that great. After bumping the load by a grain they were better. However at 300m they would hold the 4 ring, at 1000 yards they wouldn't hold the black on a DCRA target.
 
I have a check list that I run through when I’m having accuracy / precision issues.
Check action torque 45in/lbs for most actions.
Check all other screws, rings, bases etc
Check that your muzzle brake is tight and that there isn’t excessive carbon buildup.
Check your jump to lands for erosion if you have shot a lot sense load development.
Also make sure that you are “loading” your bipod the same for every shot.
Let us know what you find out.
 
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Proper load development should be done at a MINIMUM of 200 yards and ideally at 300.

Your 100 yard group does not mean much except that it shows promise.

Go to 300 with it and come back with the results.

PS ; Its part of the fun !!!!!!!!
 
Where was the mirage, was it at 300 to 400 yds, 100 to 300 yds, or was it farther out? Like 400 to 500 and farther out? Which way was the wind blowing? And at what range?
 
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