SD and extreme spread?

Speaking to 1.5 MOA at 100 and 0.5 MOA at longer range: Don't bullets sometimes "wobble" for the first 100 yards or so before they stabilize and tighten up. I see this often when shooting my bow.
 

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I went to the range today to do a seating depth test for my wife's 6.5-284. I had three depths .015, .030,.045. The only one that shot good was .015 off lands. At 100 yards it shoot 4 shots in a dime. But the SD was 29 and ES was 13.2. Does a guy just stay with this group based on group size and leave it alone ? Or is the sd and es to high and start over or tweak ? I don't know what to do at this point
4 shots is not statistical.
A 13.2 SD is not bad in the long run. Stick with what you got and go shoot.
 
@MOA or bust, Most of the info I have seen says it over before 100 yds. Bryan Litz posted this on Snipers Hide on April 27, 2012.

"The summary is that the 'corkscrew' flight path is so minor, like 0.01" in radius, that its observable effects on trajectory are insignificant. You may find some special cases where bullets having certain properties will have larger radius', but those bullets would have been identified as less accurate, and not commonly used in LR shooting."

 
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Doom2,
I hear ya, but there is an explanation for why, rarely, a load tightens up after 100 yards and I'm going with this wobble/precession idea until somebody actually figures out the answer.🤷‍♂️
 
Speaking to 1.5 MOA at 100 and 0.5 MOA at longer range: Don't bullets sometimes "wobble" for the first 100 yards or so before they stabilize and tighten up. I see this often when shooting my bow.
No, or at least not to the point that it means anything. Your groups will never get smaller at longer ranges. Litz has had an open offer to pay anyone who can prove it happens $1000 for about a decade now and no one has done it.

It either appears to tighten up at longer ranges because you're not shooting enough rounds in each group or there's some other influence on group size. Parallax is one potential cause. It could be entirely mental. Regardless, group convergence has never been documented using a shoot through target.


 
OK, so a group "tightening up" at distance is really just a fallacy. Otherwise it would be difficult to explain. Thanks for the clarity.
 
Had a guy explain it to me one time and defined groups tightening at distance as yaw, not sure that's spelled correctly, but he said bullets do not always stabilize within the first couple hundred of yards, and I had a 6.5x284 that would not shoot great groups at 100, but shot better groups at 400. I killed a whitetail with that rifle at 750 laser range finder yards. One shot, perfect conditions, right through the boiler room. I was shooting 140 grain Bergers right at 3000 fps. Folks told me it couldn't be done, but I got there with no pressure signs, and Retumbo was the powder I used. I have never experienced it again, but that one time I did find that the gun shot better at distance than close.
 
The way i read the op post is that its an moa grp size , not really a apples to apples . 100yd grp is 1.5 moa = 1-1/2"
.5 moa at 300 yds = 1-1/2"
Same size grp

For me i have not experienced a smaller grp at longer range ,except in a very windy day where my wind hold changes during the string of fire .
But that doesnt have any barring on rifle accuracy
 
I record the velocity of every shot I take at long range (and you can too with Garmin!). I have to say a shot that is 30 fps faster than average does not always hit higher at say 900 yards, at least not often enough to notice. Just my opinion; I haven't documented it but just might start.
 
I went to the range today to do a seating depth test for my wife's 6.5-284. I had three depths .015, .030,.045. The only one that shot good was .015 off lands. At 100 yards it shoot 4 shots in a dime. But the SD was 29 and ES was 13.2. Does a guy just stay with this group based on group size and leave it alone ? Or is the sd and es to high and start over or tweak ? I don't know what to do at this point
Numbers as you can see....don't mean JACK...when shooting dime size holes...you can mess with success and change it back to disaster...but why?
 
In my 6.5x284 it likes h4831sc if you have any of that you might try that. I shoot Berger 153.5 hybrid .015 thousand off and perform very well 3/4 to 1/2 moa at 600 yards sometimes better if I do my job reading the wind. I would start at 50 grain and work up to no more than 52 grains
 

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