Weird groups - by a warm barrel?

[Near miss]

Hello,

I had some fun last Sunday shooting with the family. We spent 3 hours at the range and spent around 450 shots.

But all of a sudden the gun did not shoot anymore. Groups all over the place. We packed up.

Does anyone have a guess what could cause this?

-Gun is Sako Quad .22LR
-Range 110yds
-Temp around 70s. Wind was gusty but we had one paper target fixed to move with the wind.

Below are 2 targets, I think you can also see something went sideways.
All I can think of is the barrel getting too warm, could this have this big effect? I ran a brushless Boresnake through it but it did nothing.

1. Normal groups
2. Weird groups

 

[BigTex]

What ammo? Was it all from the same lot?

 

[Near miss]

What ammo? Was it all from the same lot?

SK Biathlon and Lapua Biathlon.
Neither was hitting well once the weird shot placements begun.
Same lot.

 

[rizzle]

Is it just me or dose it look like it's key wholing threw the second target? Possible carbon ring?

 

[Near miss]

The second paper was a little bit bent by the wind, a couple of degrees.

Which is another thing got me wondering, even when the wind was mildly to the right, the shots started leaning in to left, high and low.

 

[justin amateur]

Based on similar results at 200 yards, I'd offer turbulence as the cause.
No telling where those wind caused vortices will send those trajectories.
My wind flags are spaced at 40 yard intervals at the 200 yard range.
On days where the breeze rolls over the berms or roof line,
it sheds rolling turbulence across the range. One flag will show left,
another right or headwind/tailwind or no wind at all. No way to time the squeeze.
I end up with a target that looks like a dog pound....strays everywhere.

 

[Near miss]

Based on similar results at 200 yards, I'd offer turbulence as the cause.
No telling where those wind caused vortices will send those trajectories.
My wind flags are spaced at 40 yard intervals at the 200 yard range.
On days where the breeze rolls over the berms or roof line,
it sheds rolling turbulence across the range. One flag will show left,
another right or headwind/tailwind or no wind at all. No way to time the squeeze.
I end up with a target that looks like a dog pound....strays everywhere.

I thought that the wind is playing with me but even the other fellas there could not get it right.

I also shoot in to the wind as much as possible to learn it (after first observing it) and did not get results like that before that day. I was also shooting from a cover and judging the wind by the mirage and little vegetation nearby.
The range is closed loop and usually wind enters behind me and seems to make circles inside the range.

 

[justin amateur]

I doesn't take much of a swirl to ruin a target.
The flags might not even show where it's at.
But those target results let me know what's occurring.

Think about the trajectory shifts as a bullet spits through a rolling vortex.
How are you going to predict the result?

 

[Near miss]

I doesn't take much of a swirl to ruin a target.
The flags might not even show where it's at.
But those target results let me know what's occurring.

Think about the trajectory shifts as a bullet spits through a rolling vortex.
How are you going to predict the result?

Hell no that kind of wind ain't fair!


I just took some photos of the chamber and I think I have a quite bad carbon ring there. I just realized it had around 800 or more through it during the weekend.
@rizzle

 

[BlastersAreCool]

Please keep us posted on this. What you did to clean it and if cleaning remedied the accuracy issued

 

[RTH1800]

It’s a bore issue. Wax, carbon lead etc.

 

[Near miss]

Please keep us posted on this. What you did to clean it and if cleaning remedied the accuracy issued

Hahah remember you asked for it.
I am tending it with few drops of motor oil and yes I'm of that school, I have noticed it has its time and place. I carry gun oil and Boretech Eliminator & Copper too in similar 10ml nosetip bottles, easy to dose.

After 20-50 minutes I swirled the chamber and reapplied.

After first run I swirled it with a copper brush, and applied oil with it. Did this for 3 hours, 3 or 4 runs all in all. My leg is busted so got nothing else to do anyways.
Then I snaked the barrel and took some more photos.

There is still some left, not with bare eye tho. Probably could stop here and let it be. But I am going to see if I can take it all away.

So I stick a nylon brush with cloth dosed with Terminator and see how well it will soak the rest of it.

After few minutes I pulled it and it had faint bluish/greenish tint from brush remains. Dosed little more and put it back. Swirled it. 20min all in all.
Snaked it for photos.

And damn it.. Once I got a focused photo it was still there. Impossible to see it with naked eye, even with the barrel removed so most of you guys probably have it way worse than this. But for fun I will attempt to further clean it up to 100%.

So I swirled it back and gave Terminator another 20 minutes. Snaked for photos.. But nothing had changed. I put it back for more. This time I moved it back and forth in the chamber. Then let it rest for 1 hour and snaked. Tbh nothing had changed.

After full bore cleaning it looked like this. I checked with a flashlight and it seems the remaining ring is just minor barrel nitrate coating wear.

I will be going to a course for the weekend, training 50m slinged prone. I will try this rifle there too and see the results, shooting same ammo, same lots.

 

[rizzle]

Hopefully that fixed the problem.

 

[Near miss]

It took some time to start shooting well. Me and the barrel it seems.
My whole right leg had went almost numb when I got there and it was rather disturbing to shoot with it.

55 yds, excuse me for lacking groups sizes. The 10-ring is 10.4mm/0.41".
I started with Lapua Polar Biathlon. Cold and 100% clean barrel. I think I held 2 or 3 different holdups. CB hit maybe really hit 0,5mil high. Would have been a great group.

Then I lost it and I started getting off-group at 11 o'clock.

Moved on to Topshots for the rest of the day with varying performace.

Day 2 I started with SK Biathlons and they worked wonderfully. Despite the leg bothering I also had my focus on another level. But I got tired and shaky very quickly as I have been mainly lying down past 4 weeks. By the time I finished my 30 shot score my final score was 305.5.
Below is my 1st warmup and 2nd warmup before 30 shot string.

 

[Near miss]

While I was somewhat satisfied with the results done with Lapua Biathlon I have noticed the accuracy has dropped on this barrel. After reading RRD rimfire cleaning document and seeing what kind of damage the fouling does I decided to another try.
I used modified softer than barrel metal pick which I got from ammo cardboard box and rubbed the chamber with it after long Eliminator soak.

The bad news that by feeling out with the pick I can tell there are some bad shapes in the chamber and I cannot even them out without (probably excessive) use of abrasives. Also, I noticed small pitting 1-2 inch from chamber.. I have ordered some BT Rimfire blend which I will be tending my chamber from now on.

Pick with size reference:

Chamber as good as it gets, with minor dust:

I have no problems with feeding/ejecting out of this chamber and the rifle has been quite accurate but I will be getting an aftermarket one..

 

[JG26_Irish]

When faced with a problem, usually the simplest solution is the answer. Your tgt did appear to show keyholing which implied instability. You were there and would know if the winds got wonky. I shoot at a range which often has the swirling vortex winds as depicted by Justin Amateur. Those can cause a good gun to suddenly go off but it is easy to see the impact and it is not going to cause keyholing so, I would write off wind and do exactly like you did and clean the bbl. Your bore scope shots do show a nasty carbon ring. Enough to be swaging the bullets which then just rattle down the bbl. This would cause both variance in velocity due to poor gas seal and instability due to poor contact with the rifling. Most guns require a few to upwards of 20 rds to settle back in after a thorough cleaning. It usually takes a few hundred or more rds to cause one to go off but that varies greatly depending on the bore size, amount of taper and the ammo in use. It looks like you got it pretty clean. That has to help. I have one rifle that has a worn bbl that often takes 20-30 rds to settle in after cleaning and another which rarely requires more than 5.

Irish

 

[Near miss]

I have so far once tried running Eley Tenex out of clean barrel and only first shot went off the mark. The optic was then zeroed for another cartridge.

And it is quite usual for the first shot to hit high anyways so I guess the barrel does not mind me cleaning it.

Distance was tad over 51m so 56yd.
0.5" group
The group which formed below it was 0.32".
Note, I hope I could shot 0.32" consistently but I can not and this was without any warming up so it could be smaller with a better shooter.

 

[Near miss]

For anyone interested I thought I'd make a follow up post.
This time I chronoed the cold bore group. Sadly I was not able to keep form during the string and had 2 POIs for the group. This 10 o'clock grouping is usual for me and I am working on it.
The first shot hit to the higher group though.

The below SD and ES does not include the CB shot.

Here is the Cold Bore paper, I also started testing different torques and settled for the highest torque which "locked on".

All in all, not too good shooting from me. I did test Eley Match the last time I went and got 1 moa at 109yds.
Good ammo gives confidence and the groups got improved from first to last one.

Gun is clearly not the weakest link anymore, thanks to all of you for help!

 

[Booner1334]

For anyone interested I thought I'd make a follow up post.
This time I chronoed the cold bore group. Sadly I was not able to keep form during the string and had 2 POIs for the group. This 10 o'clock grouping is usual for me and I am working on it.
The first shot hit to the higher group though.

The below SD and ES does not include the CB shot.
View attachment 7106676

Here is the Cold Bore paper, I also started testing different torques and settled for the highest torque which "locked on".
View attachment 7106716

All in all, not too good shooting from me. I did test Eley Match the last time I went and got 1 moa at 109yds.
Good ammo gives confidence and the groups got improved from first to last one.

View attachment 7106717
Gun is clearly not the weakest link anymore, thanks to all of you for help!

Near Miss,
When I look at your targets, I can't tell what your aiming at.
Do you shoot at a spot on the target and then shoot at that target hole?
I'm not being critical, I'm just wondering what your point of aim is.

 

[Near miss]

Near Miss,
When I look at your targets, I can't tell what your aiming at.
Do you shoot at a spot on the target and then shoot at that target hole?
I'm not being critical, I'm just wondering what your point of aim is.

I see what you mean. I had drawn my targets myself on a 0.4gal milk carton. The target is a black dot with red circle around it. Made with a marker.

You can see it on the target #1 (top-left) and partially on #2 and #4. And on the targets on post below.

Milk cartons do a good job showing the hole very clearly and take rain, shine and wind like nothing. I keep them folded for easy storage in my bag.
Usually I use 10m pistol targets and make small dot on the blank side. But at that range the sun shines through the paper and shows the black circle on the wrong side etc..

 

[Near miss]

I think small part of the reason my shots were so wild in the #1 post is because my Lapua Biathlon lot (not all of it though) seems to hit straight out batshit crazy.

I complained about these cartridges to my retailer already.
This target is from the same date as the earlier.
"L" for Lapua 5 shot group
"SK" for 9 and 11 shot groups of SK Biathlon on the right for comparison. I was quite quick and sloppy with them after Lapuas hit so bad.