Spring piston rifle scope not holding zero

Having trouble getting my rifle to hold zero.

Equipment:
Gamo Varmint .22 33mmOD/ 29mmID cylinder spring piston break barrel
Offset one piece scope rings
UTG bug buster 3-9x32, rear shimmed
H&N Baracuda 5.52mm 18.13gr

Shooting position:
Seated bench
Block for forward rifle support; no rear bag

Summary:
I’m looking for any advice or thoughts on zeroing my scope and getting it to hold zero. I got my air rifle about a month ago for pesting needs. Shot about 300-400 pellets through it. So far I have tried 3 different pellets and so far it seems to like barracuda 18s. Once I zero my rifle at 20yards, it can reliably shoot 1/2” groups at my shooting table and often drill the same hole. I’ve become pretty comfortable with my artillery hold although the heavy trigger sometimes makes for a tough shot particularly at ~30yards. Approximately <1” grouping.

Every so often, my zero will shift slightly when I check and shoot targets. One time I realized one of scope ring screws was loose so I checked and retightened them and then re-zeroed. Then another day it was off slightly again although holding a decent group. POI can be off both vertically and/or horizontally by 1” to 1-1/2” at 20 yards. It’s getting frustrating not being able to depend on my accuracy when I need the shot to count for pesting. Any advice?

-Should I loctite my scope screws?
-Is my scope broken? I have been trying to make sure the rings and scope are secured but also being aware of not crushing the scope. The rifle has quite a bit of kick.
-Is the accuracy shifting a sign that the barrel is still breaking in?

Really sorry for the long post. Tried to provide as much relevant detail.
 
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Well.... Maybe try toque screwdriver or inch pound wrench . To insure you tighten up stuff form wothout over doing tighting and ruin a scope or strip screws .

Ya, scoping a springer can be a hassle. Sometimes it sets firm somtimes it moves .. i e had plenty or redos or junked out scopes ..

Another thing to do is clean the rings ,base , tube , dovetail of ant lubes or oils that could cause slipping .

I find new stuff harder to keep put vs old stuff .

I guess the wheeler gunsmithing screwdriver is popular but theres plenty to choose from.


https://www.amazon.com/inch-pounds-screwdriver/s?k=inch+pounds+screwdriver

I still use a gamo gun and a gamo package scope that holds well . Then had one that did not .. .

Scopung a springer is a dice roll .
 
Well.... Maybe try toque screwdriver or inch pound wrench . To insure you tighten up stuff form wothout over doing tighting and ruin a scope or strip screws .

Ya, scoping a springer can be a hassle. Sometimes it sets firm somtimes it moves .. i e had plenty or redos or junked out scopes ..

Another thing to do is clean the rings ,base , tube , dovetail of ant lubes or oils that could cause slipping .

I find new stuff harder to keep put vs old stuff .

I guess the wheeler gunsmithing screwdriver is popular but theres plenty to choose from.


https://www.amazon.com/inch-pounds-screwdriver/s?k=inch+pounds+screwdriver

I still use a gamo gun and a gamo package scope that holds well . Then had one that did not .. .

Scopung a springer is a dice roll .
Thanks for the link and tips! I’ve just been guess-timating the torque specs.
 
Check your ring or scope manual on how much torque required . Most rings need 15+/- inlbs. But here you dont want to ober tighten and kink thd scopes tube . So best to inquire the manual or manufacturer to be sure .

The base .. 25-50 inch lbs the risk here is stripping the moune base screws or snaping one . The base screw size is the factor . I think for me 30 inlbs +/- does well , still check you partd manuals for this to be safe then sorry .
 
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Having trouble getting my rifle to hold zero.

Equipment:
Gamo Varmint .22 33mmOD/ 29mmID cylinder spring piston break barrel
Offset one piece scope rings
UTG bug buster 3-9x32, rear shimmed
H&N Baracuda 5.52mm 18.13gr

Shooting position:
Seated bench
Block for forward rifle support; no rear bag

Summary:
I’m looking for any advice or thoughts on zeroing my scope and getting it to hold zero. I got my air rifle about a month ago for pesting needs. Shot about 300-400 pellets through it. So far I have tried 3 different pellets and so far it seems to like barracuda 18s. Once I zero my rifle at 20yards, it can reliably shoot 1/2” groups at my shooting table and often drill the same hole. I’ve become pretty comfortable with my artillery hold although the heavy trigger sometimes makes for a tough shot particularly at ~30yards. Approximately <1” grouping.

Every so often, my zero will shift slightly when I check and shoot targets. One time I realized one of scope ring screws was loose so I checked and retightened them and then re-zeroed. Then another day it was off slightly again although holding a decent group. POI can be off both vertically and/or horizontally by 1” to 1-1/2” at 20 yards. It’s getting frustrating not being able to depend on my accuracy when I need the shot to count for pesting. Any advice?

-Should I loctite my scope screws?
-Is my scope broken? I have been trying to make sure the rings and scope are secured but also being aware of not crushing the scope. The rifle has quite a bit of kick.
-Is the accuracy shifting a sign that the barrel is still breaking in?

Really sorry for the long post. Tried to provide as much relevant detail.
My Diana 48 routinely knocked my peep sight loose. Springers can deliver a violent kick and often require extra attention to scopes and mounts. Solution was to install a bump stop behind the sight and a tiny bit of blue loctite on the dovetail set screws in the sight.
And even then …. you should still check everything periodically.
 
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Dug some issue pictures up on my gamo and recoil reducing rail and a mount

I got a mount that the clamp jaw was needing to be flipped over to be straight on the rail

Out of the ugt box

image24.jpg

Flipped over
image22.jpg
Stright on rail
hat95ugtmount.jpg

Then the gamo recoil rail the aluminum was kinda soft and movement was from it wallering out the stop pin hole
rrr damage2.jpg

Made bushings
scopebushingfinle.jpg2edbushing.jpg
That did the trick for that

Then the scope ring holes would "mash" down due to soft aluminum ..lol that caused the rings to be loose and required re-toquring over and over till that fully compressed down ..
mountsctewhole.jpg

If you can see i got index marks in the scope to indicate if i get sny movment .. #2 pencil does good

I had a better picy of this but cant find it ...

gamopackage.jpg
 
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If a friend showed up with the OP's complains of a moving POI where the airgun had previously demonstrated that it had good accuracy. And assuming that all the hardware is correctly torqued, ammunition is reasonably consistent, the scope parallax is properly set and turrets are not adjusted beyond its range (and "floating" the erector tube), I would assume that the shooter is in consistent in hold or triggering.

Some airguns, particularly springers are very sensitive to hold. Try paying close attention to where and how you grip the rifle and how tight/loosely you hold it. You mentioned a heavy trigger - be sure that you are contacting the trigger the same way each time and that the pull-force is straight back. Follow through on the shot, stay on target until the pellet hits.

Good luck and have fun sorting things out!

Cheers!
 
looking to see if I can find a sandbag on prime or make one of my own. My block is definitely just a band-aid for what I had lying around to use. @Hateful McNasty I really appreciate your advice and coming back to this post with suggestions and pointers! It’s given me some structure on what to look at to problem solve. Cheers everyone.
You can look around at my posts on bench or bag i shoot off and it nuttin fancy
IMG_20241026_101058882.jpg
IMG_20241023_124502705_HDR.jpg
image2.jpg

You ain't got to spend 100's or 1000's heck all that was stuff i had junk piled around and threw together and lasted for many years right to todays shooting .. no money ivolved ...😜. Just shoot and enjoy shooting.
 
looking to see if I can find a sandbag on prime or make one of my own.

Soft rest, to let that springer jump unimpeded. The harder the rest, the harder and more inconsistently that springer jumps off it. From my testing notes of over 500 airguns, including dozens of springers-

2/20/06 Shot a .25” ten-shot group at 30 yards with JSB Exacts from a soft pillow rest.

That was with a Fienwerkbau 124 springer.

Also, and just as important, duplicate your hold and contact with EVERYTHING as perfectly as humanly possible. Your results will inmprove.

.
 
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Loctite everything on a springer and torque to specs with a proper torque wrench. Unfourtunately, what you are seeing can be fairly normal hold sensitivity for a cheap springer.
Got it, thanks! I don’t mind spending the time and learning the discipline. I got this rifle as a tool and at the time couldn’t justify spending much more than the budget I set. That said, I’m starting to wonder if this might turn into a hobby as I keep eyeing these hw77/97 rifles…
 
Got it, thanks! I don’t mind spending the time and learning the discipline. I got this rifle as a tool and at the time couldn’t justify spending much more than the budget I set. That said, I’m starting to wonder if this might turn into a hobby as I keep eyeing these hw77/97 rifles…
Ya, i been eyeing a hw77 for a long time .. sadly hw pricing has exceeded the gun today ..
 
If I read correctly, you shimmed the rear of the scope? If so, this is most likely the culprit. In the short tube area of a Bug, it doesn't take much to stress the tube and reticle.
You might be on to something. I haven’t considered that. Rifle had too much barrel droop that I couldn’t adjust the elevation enough. I’ll look into it. Thanks for the thought.