POI Shift, My Old Nemesis!!!

Fliers not withstanding, it looks to me like you're tilting your rifle. That said 5mph is a pretty gentle breeze, something you'd barely notice, and in my ballistic calculator (set up for what I shoot, not what you shoot, granted) that is 2.5 inches of lateral drift at 70 yards. So methinks you're also well within the realm of what an almost undetectable change in the breeze would do to your groups. 

You need to sort the and weight the pellets to discard it, @ 70y wind start to make a big difference, a 5 second light wind gust (5mph or less) can make that or worst (and sometimes is only in the impact area, you do not feel it)

Assuming these are consecutive groups, with nothing done to the rifle or scope in between, seems to me that it's likely the result of a condition change.

I went to an orthopedic doc with back pain, and he could find nothing wrong. So I said, "then it's just a mystery? " He responded, "I like that answer and have no better." Another posibilty.

Wind and light condition PLUS rifle position hold etc. barrel conditions (hot cold clean dirty) Scope / gun cant and a mired of other possibilities 

I have the same problems (or reality). I think we have to accept this as the nature of the shooting sports.

Set a couple wind flags one on target one half way. Anything light the wind can move impact point easily. How much time difference between groups? Shot a little high power BR 6Ppc at 3500 fps 70 grain pill 100 yards and just a bit of wind feeling in your face will change impact. In competition wind would settle and the whole bench line would rip 5 shots in seconds. So what you see maybe just normal wind drift.

I’m going to do an experiment this spring. I plan to set a target at 200 yards and shoot one shot at a target . One shot out of a cold barrel and do that for at least 5 days just to see what happens. One shot per day

I also might set up an identical target next to it and shoot a second shot at that target .

My point is to see what happens in the real world with my 22-250 groundhog rifle.

See if I can depend on that first shot going to the POI and what to expect on a follow up ( should I be so lucky) 

more meaningful really then a group 

So I have two articles which may help you. Both are from the firearms world, where there are a lot more people reading and writing on this subject, but stick with me I found them both very helpful. 

https://precisionrifleblog.com/2015/05/14/how-much-does-wind-reading-ability-matter/

This guy's name is Cal Zant, and he loves to rub science on a sport where there is a lot of myth and voodoo. I've always loved his mathematical breakdowns of different concepts and problems, because it allows him to effectively communicate the significance of something. In this case he is talking about wind calling ability, and while 1000 yards with a magnum rifle and 100 with a pellet are very different, there are some significant similarities as well. I've heard people in the PRS world say that 1000 yards with a centerfire rifle is like 200 with a .22 PB. I've got a lot more experience with the latter, and if that statement is accurate, I'd say then that 100 with a PCP is about equivalent to 200 with a rimfire. Food for thought. The point I rambled away from here is that all these things are the same, just on different scales, so it matters and this shows you why and gives you some tips on how. 

https://www.ammoland.com/2018/12/how-to-estimate-wind-long-range-shooting/

There are a couple different articles out there like this one, but this one is one of my favorites. It gives you some good visual indicators which are not only practical, but allow you to start calibrating yourself and your other visual indicators. Wind speeds vary as you get closer to and further off the ground. Land can create updrafts and other features can cause wind to do all sorts of things. Where I live and shoot, I'm in an odd valley with trees and hills and obstacles, so I almost never see a single wind value from muzzle to target. So that is something to think about, how the wind is playing and where. 

Finally, I would strongly recommend picking up a weather station of some sort. Kestrel makes handheld anemometers for surprisingly high prices, however you can (relatively) cheaply pick up one of these:
https://www.amazon.com/Ambient-Weather-WiFi-Station/dp/B01N5TEHLI/

My advice is to set it up somewhere that you sit frequently and can look out the window and see the actual station itself as well as the readout screen. Not only does it provide useful data like barometric pressure for shooting and wind speed, it allows you to watch the grass and the trees and mirage and such and get real time feedback about what that ACTUALLY means. It can significantly help your ability to generate good calls. 







I hope this was helpful. I realize I'm just some nut on the internet, but it has really improved my shooting so it may also improve yours.  

I see shifts when I clean my barrel, but to swing from one target to another and change the POI that much from my experience would point towards a change in wind. 

"Am I being too picky?" 

Only if you want to maintain some semblance of sanity. If not, you can devote chingas of time and energy in retentive minutiae to reduce the POI shift to some degree.

Which begs the question (you might ask yourself), "How much POI shift will your sanity abide?"

"more meaningful really then a group"

Probably only to some people. For a military sniper or big game hunter the cold bore shot is critical. For a groundhog gun or other high volume shooting maybe the grouping after warm up is more important. Would be nice for both to coincide but often it seems that they don't.

Trying to figure out POI changes with air rifles is a fool's errand. Check your zero before hunting if possible, otherwise, try to accept it as part of the sport. In my experience, some barrels need seasoning after cleaning to settle down, others change throughout the cycle to the next cleaning. It's probably the only aspect of precision AR shooting that I find as frustrating as rimfire. Rimfires will change POI with different ammo, even of the same velocity, or, different lots of the same ammo. But air rifles seem to do it for no reason. 

Trying to figure out POI changes with air rifles is a fool's errand. Check your zero before hunting if possible, otherwise, try to accept it as part of the sport. In my experience, some barrels need seasoning after cleaning to settle down, others change throughout the cycle to the next cleaning. It's probably the only aspect of precision AR shooting that I find as frustrating as rimfire. Rimfires will change POI with different ammo, even of the same velocity, or, different lots of the same ammo. But air rifles seem to do it for no reason.

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I don't agree with the generality of this statement. It seems widely true but not always the case. It is one reason the Walther LGU I own is my go to gun for a first shot. It does not change POI noticeably from day to day. I have others that certainly do change POI noticeably and a few recent acquisitions that I don't know about yet (the Weihrauch HW44 I got recently has so far not shown much change from session to session but I don't have enough time with it to state that it "doesn't"). 

I have been following this because I experience the same thing. I even have double bubbles on my long range guns. Here is what is ironic, my drift is always to the right. That's in 177, 22, and .25 caliber. If I start printing groups off the bullseye, they are never to the left. That's why I always believed it was fixable. I set up my scopes with the gun bubble leveled and a plumb bob hung on a thick string at 20yrds to line up my crosshairs with. Do pellet guns experience spin drift at way closer ranges than real guns do?

Trying to figure out POI changes with air rifles is a fool's errand. Check your zero before hunting if possible, otherwise, try to accept it as part of the sport. In my experience, some barrels need seasoning after cleaning to settle down, others change throughout the cycle to the next cleaning. It's probably the only aspect of precision AR shooting that I find as frustrating as rimfire. Rimfires will change POI with different ammo, even of the same velocity, or, different lots of the same ammo. But air rifles seem to do it for no reason.

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I don't agree with the generality of this statement. It seems widely true but not always the case. It is one reason the Walther LGU I own is my go to gun for a first shot. It does not change POI noticeably from day to day. I have others that certainly do change POI noticeably and a few recent acquisitions that I don't know about yet (the Weihrauch HW44 I got recently has so far not shown much change from session to session but I don't have enough time with it to state that it "doesn't").

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Yes, I have a couple that are relatively stable day-to-day as well, a Steyr Challenge Hunting (strange label for a single shot with no safety) and, so far, my Red Wolf. The consistency of the Steyr does not surprise me, offering typical Austrian simplicity, without a bunch of stuff complicating the barrel attachment system, just a bare, floating barrel. I suppose, given the light and relatively slow projectile, we should expect POI variations with significant weather changes. In other cases, I'm sure there is a reason for every POI change, but I sometimes can't find it. As a class, I have found air rifles to be a finicky bunch, as compared to their metallic cartridge cousins, but there are exceptions. If I remove the suppressor from my Brocock Bantam for transport, or to put on another rifle, when I attach it back on the Bantam I can expect a POI change, sometimes substantial. The Red Wolf, which uses a similar shroud arrangement remains on zero after such shifting around. Of course, none of this matters much for shooting targets or bouncing around cans or bottle caps, since it takes only a few minutes to check the zero. But, it can be problematic in a hunting scenario.