Help with POI drift on .22 PCP rifles. Temperature or something else?

[JelloStorm]

Hey everyone,

My friend and I hunt starlings and I use a non-regulated Barra 1100Z while he uses an Air Ventruri Avenger bullpup and we're having a heck of a time trying to keep our guns zero. We're shooting at 35-40 yards so nothing crazy.. We're always paying attention to wind etc..

Upon filling my Barra to around 2700-2800psi I have to re-zero it and it will hold zero until the sun starts shining on the gun, and then I get a POI drift of around .8 mils right/left and a maybe .5 mil vertical throughout the day. My friends Avenger does the same thing and his is regulated. So I got some rattle can OD green and painted the barreled action a lighter color than black to hopefully stop the thermal expansion. Doesn't really seem to help.

My friend on the other hand lives on some land so he's constantly looking out for pests to smoke, however he cannot in good faith take a shot because the damn gun will drift while it sits inside. We're in PA where it's not crazy hot/cold right now and house temps are just about outside temps. We have to take periodic breaks from hunting to verify zero of our guns and adjust it back which is almost always necessary...

We run a massive filter so there's almost no moisture going into the gun. We both use good rings (he uses Vortex rings) and we've tried multiple scopes so it's not the scope drifting. Our rings are torqued down properly and everything just like I do with my centerfire rifles.

Can anyone tell me what in the hell is going on with our guns? Even a cheap Crossman pump pellet gun doesn't do this shit to that degree.

Really appreciate any help anyone can offer!!!

 

[acourvil]

I can't speak to the guns you guys are using, but I have seen the same thing to a lesser degree. Air guns in general just aren't built as solid/stiff as firearms. You can go through the usual exercise of checking to make sure the barrel is fully floated, that there is nothing making contact where it shouldn't, making sure things are torqued consistently, etc., and that should help. One item that is often an issue is the shroud/moderator; if it is not perfectly tight and centered, it can really play around with the POI. I have had decent success getting my guns to hold a zero when I am out in the field, but if the gun has been sitting for a while, or getting banged around while traveling, I almost always check my zero and often have to make a small adjustment.

A .8 mil drift is a lot, so if you haven't already you might want to work through all of the connection points and fasteners and make sure there isn't something that is loose. It's also possible it is a scope issue, so if you have a known good scope you might want to swap it and see if the same thing happens. Good luck.

 

[JelloStorm]

I've used Vortex scopes and now use an Element Helix 6-24 mil/mil. Once we get them zero, they're tack drivers but then it'll just start to drift as temps change.

 

[steve123]

Unfortunately this is one of the most prominent problems with pcp airguns.
It's part of the reason I don't even try the less expensive airguns anymore and there are some expensive ones that have POI shifts too.

One thing I've noticed throughout the years is that if the gun has a barrel band/barrel brace that touches the barrel it'll cause POI shifts. You can drill it out a little so it doesn't touch anymore.

Also if you can prevent a shroud from touching the receiver that helps.

If you still want to use pcp's I suggest selling those guns you two have and stepping up in price and quality. The trick is finding pcp's with rigid barrel mounting systems.

One that can be had at a good price used is the older FX Royale.
RAW's are pretty good.
Daystate are decent.
Mac1 USFT was by far the least as far as POI shifts for me.

For power I like AGT Vulcan 3 and it holds zero well.

 

[Scopeye]

Hey everyone,

My friend and I hunt starlings and I use a non-regulated Barra 1100Z while he uses an Air Ventruri Avenger bullpup and we're having a heck of a time trying to keep our guns zero. We're shooting at 35-40 yards so nothing crazy.. We're always paying attention to wind etc..

Upon filling my Barra to around 2700-2800psi I have to re-zero it and it will hold zero until the sun starts shining on the gun, and then I get a POI drift of around .8 mils right/left and a maybe .5 mil vertical throughout the day. My friends Avenger does the same thing and his is regulated. So I got some rattle can OD green and painted the barreled action a lighter color than black to hopefully stop the thermal expansion. Doesn't really seem to help.

My friend on the other hand lives on some land so he's constantly looking out for pests to smoke, however he cannot in good faith take a shot because the damn gun will drift while it sits inside. We're in PA where it's not crazy hot/cold right now and house temps are just about outside temps. We have to take periodic breaks from hunting to verify zero of our guns and adjust it back which is almost always necessary...

We run a massive filter so there's almost no moisture going into the gun. We both use good rings (he uses Vortex rings) and we've tried multiple scopes so it's not the scope drifting. Our rings are torqued down properly and everything just like I do with my centerfire rifles.

Can anyone tell me what in the hell is going on with our guns? Even a cheap Crossman pump pellet gun doesn't do this shit to that degree.

Really appreciate any help anyone can offer!!!

First thing to try is to only single load each and every shot to see if the magazines are damaging the pellets causing your fliers assuming your air rifle is magazine fed. I am not familiar with the Barra but do know the Avengers are notorious to throw fliers due to the barrel end not being rigid.

The next step is to change to a better quality scope at least an Athlon Midas BTR G2 4.5-27x50 or Midas Tac 6-24x50 and better yet, the Ares BTR G2 4.5-27x50 for $565.49 with free shipping and free returns at Walmart online and is night and day way better quality than the Element Helix.

You aren't the only one having issues with the junk Chinese Element Helix. Just the terrible eyebox is enough to throw fliers plus I bet your elevation is already maxed out if you are using the 6-24x50 Helix which is another problem.

 

[tacops1]

I have a fix the the Air Venturi Avenger and it will shoot lasers

 

[tacops1]

For any standard Air Venturi Avenger the first upgrade I do is this … black arts barrel band it’s a hell of an upgrade for improved design and accuracy

Black Arts Barrel Band System for Air Venturi Avenger | Pyramyd AIR

We've got a great price on Black Arts Barrel Band System for Air Venturi Avenger at Pyramyd AIR. Shop where the experts do!

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Next I do this ….. Donny FL thread adapter and it aligns the barrel a bit better for use of a mod or no mod

DonnyFL Air Venturi Avenger Extender 1/2 x 20 Adapter | Pyramyd AIR

We've got a great price on DonnyFL Air Venturi Avenger Extender 1/2 x 20 Adapter at Pyramyd AIR. Shop where the experts do!

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Then I add this ….Donny FL quick detach mod makes that mod go on same way every time

https://donnyfl.com/products/quick-...5&_sid=62fb56978&_ss=r&variant=40897486323755

The add a Donny FL mod like an FX and JSB EXACT JUMBO HEAVY DIABLO 18.13 grain domed pellets

That gun will be a laser beam and quiet as hell and smack em hard you will thank me I had no poi issues no
More

 

[Precision Quest]

Yeah, air guns shift point of aim and are more temp sensitive then .22's. Drives me crazy, pull the liner to clean my Impact and it shoots 2 MOA higher...crazy.

 

[tangolima]

I would shoot the gun indoor to eliminate the ambient factors; temp, wind, lighting etc.

Maybe a silly question to ask; did you adjust the scope's parallax correctly?

-TL

 

[JelloStorm]

We use them for hunting birds. We can take the gun from indoors ~70F outside to ~30F and watch the POI drift across the paper as we shoot.