accuracy problems - duh

[wabi]

In a recent thread I mentioned I'm having a strange accuracy problem. Sight in and all is good for a few days then POI suddenly shifts. Re-zero and all is good for a few days then the problem repeats.

I use a rope cocking aid, and all the screws are tight. I even replaced the rings with a new set of steel rings and my groups tightened up. I was hoping the problem was solved, but today I checked it at the range and POI had shifted again.

Re-zeroed and thought to myself, "one more chance, then it gets a new scope!"

This evening I was going to hunt. Grabbed the quiver, my pack, and the Phoenix. I noticed some dirt on the front of the scope. When I tried to wipe it off I found the lock ring was loose!

Duh.............. How did I miss checking that?

It took almost a full turn to tighten it, so I'm hoping that was my accuracy issue all along.



Might be something else to check occasionally.

[B-Logger]

That is good that you were able to find the problem. Now you can hunt in peace.

[Cossack]

Mine was behaving the same way. Had me doubting my Vortex, until I confirmed oit was indeed the scope. I returned it to Danny Miller for replacement, problem solved.

[kennisondan]

the back to basics thing is usually the place to start.
dk

[sumner4991]

Sometimes you just can't see the forest for the trees. I hope your troubles are over.

[ComfyBear]

Mike, according to your pic, the "lock ring" that you're referring is not a locking ring. The locking ring is the one on the back of the scope.

The front ring should have nothing to do with your accuracy problems. It's just a lense "hood". Its only function is to shade the objective lense from extraneous light. As such I'd be surprised if tightening it would fix your problem.

[saxman]

I hope that fix's the problem Wabi
Good luck.

[wabi]

Mike, according to your pic, the "lock ring" that you're referring is not a locking ring. The locking ring is the one on the back of the scope.

The front ring should have nothing to do with your accuracy problems. It's just a lense "hood". Its only function is to shade the objective lense from extraneous light. As such I'd be surprised if tightening it would fix your problem.

Actually that rind does lock the lens from moving. It can be removed and the lens turned in or out for parallax adjustment. It won't make a huge change in POI, but that was what I was experiencing, a shift of a couple inches at a time.

[bbbwb]

A friend was having similar problems in that it would shoot fine this shot and the next would be off. He was using a rope cocking aid and so thought there was consistency in the cocking.However, on careful observation it was noted that he was not being consistent in the use of the aid. He was not making sure the hooks of the aid were next to the rail when cocking. Upon keeping this consistent the wandering shots were eliminated.

bbbwb

[ComfyBear]

Actually that rind does lock the lens from moving. It can be removed and the lens turned in or out for parallax adjustment. It won't make a huge change in POI, but that was what I was experiencing, a shift of a couple inches at a time.

Mike, are we talking about Excalibur scopes Is there something I don't know. I've owned both the Vari and the Lumi, and from what I know, neither allows for adjustment of the front lens. The only adjustment, other than magnification, is the focus by turning the rear ocular lens.

[wabi]

Actually that rind does lock the lens from moving. It can be removed and the lens turned in or out for parallax adjustment. It won't make a huge change in POI, but that was what I was experiencing, a shift of a couple inches at a time.

Mike, are we talking about Excalibur scopes Is there something I don't know. I've owned both the Vari and the Lumi, and from what I know, neither allows for adjustment of the front lens. The only adjustment, other than magnification, is the focus by turning the rear ocular lens.

It is a factory adjustment made before the scope is shipped. It is not an adjustment the user would make, and is something to avoid tinkering with because it is easy to loose the nitrogen fill and change the parallax setting.
The front lens is mounted inside a threaded tube (outside threads) that in turn is screwed into the main scope body tube. The amount it is turned in determines the specific distance of parallax free viewing through the scope. Screwing the tube in or out will change the parallax setting. The front ring I pointed out in the pic is what locks the tube in which the front lens is actually mounted in place.

[ComfyBear]

OK, I understand now. Thanks for the explanation. One never stops learning.