What would make a 100yd group open up by a factor of 5x at 200yds?

[JimSC]

my advice ..practice practice practice then practice some more. You have a great rifle and scope. You should be able to halve the 100 and 200 yard group sizes. Don't sweat the ES when shooting less than 500 yards. This target was shot at 300 yards with a Savage 12 and a Sightron 6 - 24 scope. ES is stupid high at 99, SD of 40. Group height was 1.262 inches for 5 shots. 10 and 20 shot groups get about the same vertical. If you want to play with your reloads might try a different weight bullet. 69's, 77's or 80's or the heaviest your barrel twist will handle

 

[edwardware]

I know MOA size can be expected to open up some as the range increase, but 5x from going from 100yds to 200yds is ridiculous.

I'm not some Benchrest wizard, but I do shoot a lot of 100-300 yard target, and I reload. I don't think any of the subtle effects we chase (like ES, BC, etc) are nearly significant enough to do that. An ES of 100fps is typical from factory ammo, and plenty of rifles run ~MOA to 300 with that ammo.

So, that leaves you; I guess you're doing something different. I'll start by pointing to your targets; if that orange dot is anywhere near ideal size at 100, it's way too small at 200. Make sure you can see the targets.

Second, shoot two, 5-shot groups at each range before you pretend to know anything. If the group sizes aren't well-correlated, you've found your problem. Your inconsistency is swamping your sample size.

Remember that silly idea about bullets 'falling asleep' after 100 yards? Besides demonstrating the ignorance of people who say that (if it were true, it would violate entropy and require time travel. . . information flowing backwards in time), it illustrates that many shooters are so much more careful aiming at a further target that their groups are noticeable smaller (angular dispersion) on the further target, and they have no idea they're doing it. I suspect you're doing something similar, just in reverse from the usual.

 

[Shinbone]

Yup, more shooting and more groups are needed before any real conclusions can be drawn.

I've been told: "Don't try to force the rifle to shoot something it doesn't like." Accordingly, I'm going back to square one and will start with a different powder and bullet. Seems like SMK's 69gn and Varget is a good starting point. I'll also simultaneously work with N135 and a bullet in the 55gn weight range. too. I also ordered Lapua brass, to replace the Starline brass I was using.

Different rifle, but here is my shooting set-up:


1" orange dots were used at 100yds; 2" orange dots were used at 200yds.
2 foulers were shot before shooting for group. I do agree that it looks like that Kimber barrel is "settling in" after cleaning. Maybe it needs more than 2 shots to properly foul.

Here are the .22 bullets I have on hand:

 

[243winxb]

 

[Coyotefurharvester]

Kimber barrel is probably a 12 twist, will likely need to stay 60 gr bullet or lighter. Focus your reticle following scope manual and leave it set.

 

[Shinbone]

243winxb - Thanks for all that great info!! And, I had considered neck turning just to eliminate neck tension as a possible variable, but your results tell me to hold off on that, at least for now.

Factory specs put the Kimber barrel twist at 1:9, and the Ruger barrel twist at 1:9, as well. I will measure to confirm.

 

[jelenko]

Personally, I'd run the whole test over at least one more time - paying attention to consistent technique and, of course, ensuring the forend, i.e., not the barrel, is on the bag.

 

[joshb]

My eyes are old, I like 16-20x and a 0.25 moa dot for load development. I have seen scopes shift poi when changing the ocular focus, that and power setting. Need repair or replacement. Seen people rest the barrel on bags and wonder why groups open up greatly as distance increases.

“Old?” I must be ancient! I don’t do load development with any scope less than 36 power.

 

[Shinbone]

Personally, I'd run the whole test over at least one more time - paying attention to consistent technique and, of course, ensuring the forend, i.e., not the barrel, is on the bag.

The gun is positioned so that the recoil lug sits over the rest.

 

[jelenko]

going back to square one and will start with a different powder and bullet.

As others have suggested, run the same components at least 1-2 times more to confirm.
Without wind, group size stays pretty much consistent at different distances. Without duplicating the tests, your assumption should be that you are the difference between your 100 yard and 300 yard groups.
With any of your rifles, what is the smallest groups you've seen?

 

[M-61]

"I did have to refocus the reticle when moving from 100yd to 200yd on both scopes -"


The focus of the reticle is set by staring briefly at the wall in your house as example. Once it's sharp and clear for your eye that's the end of it. To be changed only if your eyes have. Not changed for range.

 

[Shinbone]

As others have suggested, run the same components at least 1-2 times more to confirm.
Without wind, group size stays pretty much consistent at different distances. Without duplicating the tests, your assumption should be that you are the difference between your 100 yard and 300 yard groups.
With any of your rifles, what is the smallest groups you've seen?

This with a Winchester M70 Extreme Weather:



I've been handloading for about a year, so I don't have many examples to draw from, yet.

 

[jelenko]

Cool. How many groups did you shoot with that rifle and that same load? Of those groups, how many were close to the same size?
My questions are simply for you to decide whether you're confident that your technique is consistent enough to reliably shoot groups that are limited by the gun/ammo.

 

[Shinbone]

jelenko - Thanks for your questions. I am not a competition shooter, just an accuracy-minded hunter. I can certainly stand to improve both my bench rest shooting and my handloading. That being said, I can reliably shoot at least a 1", 5-shot group at 100yds with a rifle set-up as shown in my Post #23, and have done so many times with multiple rifles. But, your point is well taken that if the shooter is not up to it, how good your rifle or loads are is irrelevant.

 

[charlesasmith]

I am with joshb about using a higher power scope for load development. A thick reticle and 9 power for 200 yd group testing would be impossible for me. But, I am older than dirt.

Chuck

 

[RGRobinett]

Its that wind, i know it is.

Yes, it's mostly this - Dusty is correct again! If you, "do the math", you will find that the wind drift factor, from 100yd, to 200yd, is 1.43333! That's right - wind flags rule!
The wind drift numbers for a 68gr 6mm bullet, about .27 G1 BC, at 3400fps MV: 100yd. 0.090" per MPH, or, 0.90" in a 10MPH breeze; 200yd 0.39" per MPH, or, 3.90" in a constant, perpendicular, vector 10 MPH zephyr. Yes, it's four times more difficult to shoot a 2" group at 200yd than a 1.00" group at 100yd.RG

P.S. That said, the wind may 'giveth' , or, it may 'taketh' away!

 

[JFrank]

^^^The time between shots is enough to eat a snack , lots of little changes happening

 

[Dusty Stevens]

Theres that pesky math again ^^

there is never a no wind situation. Scopes that are just broken do not open groups 5x without rattling. Neck turning nor mixing in different weights of bullets into the same group does it either. Wrong twist rates nor dirty barrels do it either. A 223 is one of the most forgiving cartridges out there for little mistakes, but there aint a cartridge made yet that will shoot thru the wind- your targets are a perfect example of what changing conditions do to a group. Next time you think theres no wind at all start a fire and watch the smoke

 

[JFrank]

Except the mighty Creedmoor

 

[Ccrider]

Check the torque on all screws.

The large spread in your es makes me wonder if you are doing something problematic in your reloading process that is effecting your accuracy. Buy a box of factory ammo and see how it shoots. I have never bought a factory rifle that shot 5 moa or anything close to that. I have seen a lot of hunters that could not shoot much better than that.

Has this barrel shot any load accurately consistently? 1 inch at 100 is not 4 to 5 inches at 200 unless the wind or the shooter is causing the spread.

How many rounds down the barrel. What condition is it in? Borescope the barrel.