Groups moving around? Maybe your scope is the problem.

Forums Optics, Scopes, Rings, & Mounts Groups moving around? Maybe your scope is the problem.

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    biohazardman
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    I had problem with my groups moving around five shots here and five shots there in succession and fought with this for several days.  Until I grabbed the ocular fast focus eyepiece and noticed it was loose.  Cheap UTG compact tactical scope.  When I looked through the scope and wiggled the fast focus eyepiece the reticle moved with it.  I was about to toss the $140 scope when I remembered how the scopes of yesteryear had a threaded ring that tightened down on the eyepiece once you had it adjusted correctly.  So, I stuck an o-ring and the appropriate length of piece of plastic, for my individual focus, between the ocular and rear bell assembly on the scope and tightened it down.  Ah, that is better no more movement and no more wandering groups!

    Well I recently picked up an LCS SK-19 in .22 so pulled my old Falcon Menace scope out of the retirement drawer checked and found the same problem a loose fast focus eyepiece so I understood why I retired it.  Looking around for some repair parts I found an unused 1 1/2 inch kitchen drain washer and an o-ring just sitting around waiting for some purpose in life. I stretched the o-ring over the ocular and rolled it into place then slid the split drain washer into place.  I then screwed in the fast focus eyepiece until it butted up against the drain washer snugly.  No more play in the eyepiece and no more wandering groups and I saved myself from having to replace the $400 scope as well. Such an easy but permanent repair. The only negative with the repair is that the scope is now focused for my eye only.

     

     

    Almost fergot my Hawke scope in the retirement drawer also with fast focus problems. Looks like I have already done the repairs to it.

    I really hate the fast focus thing to me it is just a marketing ploy to give us an inferior product and make us think it is superior cuz it's a new idea. When acually it is cheaper because there is one less part to be made and machined.  They could fix it by simply putting a spring inside the rear bell to hold things tight or give us the threaded ring back. When scope shopping last I picked up a Leopold for $1000 and before my purchase I made sure it had the locking ring on it so I would not have this problem again.

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    Motorhead
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    Indeed … have for years now placed stacked o-rings into the gap of fast focus eye pieces to take out the wobble.

    Trick works very well indeed !

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    JoeWayneRhea
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    A well fitted oring can solve a lot of scope issues . I have one that the side focus refuses to stay put . Oring to the rescue ! It's hard to turn now ,but never wanders

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    Diamondback
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    Nice!

    I have dealt with this many times.

    I thought about trying heat shrink to lock down the eyepiece once it’s adjusted to my eye, maybe using layers of the stuff, in computation with your orings?

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    biohazardman
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    Motorhead

    The original UTG scope was some years back the Hawke was a few months back and the Falcon was just recent so it is a continued saga.  There is really no excuse for this kind of thing the makers have to know it is a problem.

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    biohazardman
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    Diamondback

    Nice!

    I have dealt with this many times.

    I thought about trying heat shrink to lock down the eyepiece once it’s adjusted to my eye, maybe using layers of the stuff, in computation with your orings?

    O-rings are good because they leave a bit of a cushion for slight adjustment as your eyes change over the years.  Yet they hold things tight enough to stop any wondering groups.

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    biohazardman
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    JoeWayneRhea

    A well fitted oring can solve a lot of scope issues . I have one that the side focus refuses to stay put . Oring to the rescue ! It's hard to turn now ,but never wanders

    I would have to agree with that.   They can tighten and fix loads of things that need it.

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    profsrgary
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    Thanks to all who posted on this thread. I have a UTG true hunter on an Mrod and yesterday morn the poi shifted 1.5" at 32 yards. Took it down to my indoor range of 12 yards and poi shifted every time I bumped the turret area of the scope. Contacted Leapers but have not a response as of yet and don't expect one for a day or two because of the weekend. I also have the same model scope on my Gamo Mach1 and figured poi shifts were caused by different holds. Modified both scopes as shown in pic and WOW!The pic shows the adjustment ring before turned in. When I turn it clockwise to adjust it actually pushes the red oring into the fixed piece.This gives me about 1/2 turn of adjustment and takes all wobble out of the equation. This forum ROCKS!

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    bandg
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    One of the internet "experts" argued with me incessantly a while back, stating that movement in the eyepiece cannot cause any change in the perceived reticle position.  This is one reason I like Hawke Sidewinders-they have a locking ring for the eyepiece.  But the o-rings are a great idea for those scopes that don't.  There are also shaft collars available that should do the same thing but I've never tried one.

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    profsrgary
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    bandg

    One of the internet "experts" argued with me incessantly a while back, stating that movement in the eyepiece cannot cause any change in the perceived reticle position.  This is one reason I like Hawke Sidewinders-they have a locking ring for the eyepiece.  But the o-rings are a great idea for those scopes that don't.  There are also shaft collars available that should do the same thing but I've never tried one.

    It is interesting that you mention this. As I said I have two exact scopes. Both of the eyepieces would move around. However the one on the PCP had the crosshair moving and the image staying stationary. The scope on the Gamo allowed the entire image to move with the crosshair.

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    bandg
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    profsrgary

    bandg

    One of the internet "experts" argued with me incessantly a while back, stating that movement in the eyepiece cannot cause any change in the perceived reticle position.  This is one reason I like Hawke Sidewinders-they have a locking ring for the eyepiece.  But the o-rings are a great idea for those scopes that don't.  There are also shaft collars available that should do the same thing but I've never tried one.

    It is interesting that you mention this. As I said I have two exact scopes. Both of the eyepieces would move around. However the one on the PCP had the crosshair moving and the image staying stationary. The scope on the Gamo allowed the entire image to move with the crosshair.

    Interesting.  I'm far from an optics expert but I know what I saw in the specific occurence that I mentioned-the reticle moved in relation to the target.  I don't recall if it was the entire image or just the reticle but it moved.  Could entire image vs reticle movement only be related to FFP vs SFP?  In any event, I prefer locking rings on eyepieces and will be adding o-rings to those scopes I own that don't have locking rings.

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    Bob-in-WV
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    I have had that problem as well.  I fixed mine with a few wraps of black electrical tape around the focus piece and scope tube.  Doesn't look bad and keeps it from moving.

     

    Bob in WV

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    Duckfish
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    Just as good 

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    Duckfish
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    Speaking of ocular adjustment.  Read the A team instructions on how they set up their scopes ( head bob) .  I do it on all my higher powered scopes.  It works.

     

     

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    whyzee
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    Duckfish

    Speaking of ocular adjustment.  Read the A team instructions on how they set up their scopes ( head bob) .  I do it on all my higher powered scopes.  It works.

     

     

    Could you post the link to these instructions please?

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    biohazardman
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    whyzee

    Duckfish

    Speaking of ocular adjustment.  Read the A team instructions on how they set up their scopes ( head bob) .  I do it on all my higher powered scopes.  It works.

     

     

    Could you post the link to these instructions please?

     

    I think this is what he is talking about.

    https://www.bcsportsmen.org/ft/A_Team_Parallax_adjustment_procedure.pdf

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    Duckfish
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    Bingo, 

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    Chachoze
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    Thanks for posting the link Bio,  I had stumbled across this once before but lost track of where I found it and couldn't find it again.

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