What causes a scope to lose its zero?

[Power Pill]

I haven't experienced it, just wondering.

 

[ajax]

various things, poor workmanship of the internals,recoil,been battered around!

 

[Brian46]

usually a poor quality scope coupled with heavy recoil, there are lots of other causes as well but mostly have to do with poor care and/or abuse of some sort.

 

[Toomanyguns]

Only happens if I turn the dials.

 

[CyaN1de]

Temp, humidity, altitude and density altitude will all affect your POI from week to week, day to day and even hour to hour some days which may make one think their scope's zero is changing.

 

[pazzo]

Won't happen if you invest in a good quality scope (~$2500 CAD to start, IMO)

 

[starpuss]

have a good "set" of rings. help and good scope base. like this

 

[Ice-Pick]

Cheap scope / rings.

Had jr shooting an SL-8 and he didn't notice the Quick release rings coming loose so he kept adjusting the scope, oops.

X2 toomanyguns, laff.

 

[Ducimus]

Is says Bushnell on it.

 

[peterdobson]

One cause is spring controlling erector lens tube going weak.

 

[brownie]

if the barrel is not free floated in the stock the point of impact will change when a change in temp or humidity warps the stock.

 

[Power Pill]

Won't happen if you invest in a good quality scope (~$2500 CAD to start, IMO)

How about a $100 (5 years ago) Bushnell banner?

 

[brotherjack]

Temp, humidity, altitude and density altitude will all affect your POI from week to week, day to day and even hour to hour some days which may make one think their scope's zero is changing.

Only if you're in to wood-stocked rifles.

Oh wait... wrong thread....

 

[Gatehouse]

Usual causes of loss of zero are the name TASCO or BUSHNELL on the scope.

 

[Power Pill]

Usual causes of loss of zero are the name TASCO or BUSHNELL on the scope.

Hope the Bushnell part was a joke

 

[Gatehouse]

Hope the Bushnell part was a joke

Nope, I've had Bushnell scopes lose zero a few times. Don't use them for hunting anymore, but I haven't tired the new 6500 series.

 

[aletheuo]

Only if you're in to wood-stocked rifles.

Oh wait... wrong thread....

I find a wandering zero to be less boring. Gives you something to think about while squeezing the trigger on that giant trophy buck.

 

[newfierob]

that is like asking what causes a woman to go nuts for no apparent reason. the reasons are varied and sometimes hard to diagnose... seems the old rule about fixed power scopes being the best bet for reliablity is still true... oh and women with fake ones.

 

[FLUXCORE]

have a good "set" of rings. help and good scope base. like this

Did you lap your rings? You could really twist around a scope tube if your rings were off.

 

[brotherjack]

I have never owned a single scope, from the cheapest to the most expensive, that had a zero holding problem (not counting the time I accidentally dropped a rifle scope-first on a big rock from a height of about 5 feet -- the rear bell was (and still is) bent, and yes, I had to re-zero after that, and yes, it's held zero since then -- the scope in question is a $50 Bushnell Sportsman, of all things to boot).

I have, however, owned a surprising number of rifles that would not "hold zero" and/or needed a LOT of tedious work before they would shoot consistently. I tend to think that there is lots of blame thrown at optics that really should be thrown at the rifles themselves (especially those who are a fan of wood stocks, that don't take the time to have them properly (and heavily) glass beded).