To modify Daisy 880 or purchase a better for $150 or less?

Those guns are not built all that well so it can be hard to get on target and even harder to get to stay on target.

With the limited budget you are not going to do allot better though. But with another $20 you can step up to a Benjamin 397 or 392, from Crosman, on free shipping Fridays. These are much better pumpers and built to last decades. Although they are out of stock at the moment they would be well worth waiting for. You could also get a nice co2 rifle for the money but they cost more to shoot. I am not much of a cheap spring gun guy as they are hard to shoot accurately and tear scopes up. Still there are plenty in your price range.

https://www.crosman.com/benjamin-392-22


 
Epoxy the barrel to make rigid and not wobble like it normally does and buy a better scope you should be able to get sub half inch groups at 25 yards with the right ammo.

You can also stick a shim to point/wedge the barrel to point on the same direction your scope lost adjustment due to maxing it out too of you don't eamna pay money for a new scope. I would try this first. Try a toothpick to wedge it.
 
https://thecmp.org/sales-and-service/sporter-air-rifles/

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Added the AA CZ200T if you want another good gun or for others reading who are interested they can be hot rodded to 12fpe to shoot 70-80 yards easy.


 
One from the CMP would be outstanding! However, you are in the drivers seat. 

I like to tinker, and read everything I can find on a brand of airgun.

There are a number of simple mods that can be done to an 880, 

and a number of airgunners out there that hunt and/or pest with them!

(but it will need a better scope!) JMHO




 
Epoxy the barrel to make rigid and not wobble like it normally does and buy a better scope you should be able to get sub half inch groups at 25 yards with the right ammo.

You can also stick a shim to point/wedge the barrel to point on the same direction your scope lost adjustment due to maxing it out too of you don't eamna pay money for a new scope. I would try this first. Try a toothpick to wedge it.

Thanks Odoyle, 

I'm new to this. Are there threads and/or pictures on how to epoxy the barrel and where to shim the barrel? 
 
I upgraded my 880 scope to a Winchester 4x32AO and I modified my trigger by sanding down ~0.8mm off the hammer/sear interface. This greatly improved my accuracy. The scope can be found on amazon sometimes as low as $30. The distance markers on the AO were slightly off on my scope, but you can figure out how to set it by using the bobble head test (there's a good video on youtube showing the bobble head test for AO scopes).