3-9 vs 4.5-14. Please help

wyoboypt

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Ive hunted 22 years with the 3-9x40 vx2 my dad put on my rifle. It’s an awesome scope. Rock solid. Recently I purchased a new rifle and put a 4.5-14 on it. It seems that it requires more effort and more perfect eye placement to get a full image in the scope even on low power. I can shoot my 270 w the 3-9 with my backpack on or off with 0 effort. The new scope not even. Leupold rep told me that the newer 3-9s will not be any better than the 4.5-14 for eye relief, as in the new ones don’t have as big an eye box as the old scopes??? Do I need to try to make more adjustments to make this new scope work? Or should I search for an old vx2? I’m a rookie when it comes to shooting tech and rifle scopes. As is already stated I’ve used the same rifle since I began and never changed anything except the bipod. Thanks
 
Kind of funny. I’m in nearly the exact same situation down to the caliber gun. Except the 3-9 I took off my rifle was an old vortex, but I did notice the exact same thing you described here with the VX3 4.5-14 CDS

I imagine it will become more natural with time, after shooting the same scope for a while I think we get very used to how they feel, even if they aren’t necessarily better. Interested to see reply’s to this thread, though.
 
The information I found on the VXII 3-9×40 eye relief is 4.2-3.7
The VX3 4.5-14 is 4.4-3.6
So not enough difference for me to tell. Have you tried to move your scope to see if that helps? I always keep my scope loose, close my eyes, mount the gun to my shoulder, and then open them until I have a perfect sight picture. Once I do that I make sure everything is level and torque down the rings.
 
Adjust the scope closer to accommodate eye relief. I found that the higher magnification is more critical on Leupolds than the Zeiss’ that I have used, but I have not had as much of that issue out of my VX5 HD as my VX3is. I usually use my scopes on lower to mid settings, and rarely crank them all of the way up, but I do adjust them back
 
New setup have the same stock length (LOP), cheek stock height and base/rings/scope relationship? Change any on these items from old reliable will be somewhat similar to jumping on your friends bicycle.... seat height, pedal travel and handlebar placement may all be close but not the same, resulting in a very different feeling while riding the new bike.

Getting to see the whole field of view at the furthest eye relief while wearing your bulkiest clothes to be used in a shooting situation allows for less chance of scope bites on severe uphill/downhill shots, especially if not wearing all the layers with your face creeping forward.
 
The sensitivity to eye position is related to the size of the exit pupil. A larger exit pupil diameter allows more eye movement without interfering with the image. The exit pupil diameter is the objective diameter/power. A 6x42 has a 7mm exit pupil. 42/6=7. If both your 3-9 and 4.5-14 have the same objective LENS diameter, then they will have the same exit pupil diameters from 4.5x-9x. Obviously the 3-9 will have a larger exit pupil from 3x-4.5X simply because the power is lower, and the 4.5-14 will have a smaller exit pupil from 9x-14x because the power is higher. BUT from 4.5-9 they would be the same. If the 4.5-14 has a larger objective lens, then it should actually have a larger exit pupil from 4.5x-9x. Of course it could go the other way. Next, eye position is not just side to side, but also front to back. If you mounted your new scope in a position such that you’re not at the proper eye relief distance, then you’re using less of the available exit pupil diameter, and thus your scope would seem to be more sensitive to side to side head movement than it should be on paper.

If you downsized your objective diameter, then you’re just stuck with a smaller exit pupil and more sensitivity to eye position. If not, then you might want to adjust where your scope is mounted.
 
I would suggest pulling the scope closer to you as you are tucked into the gun and mount it that way. I had the same problem so I and ended up mounting my scope on a pica tinny rail and match grade rings. It worked and shoots tacks now!
 
Check length of pull and drop for correctness. I mounted a leupold scope on low rings and still needed a comb pad for proper eye alignment.
 
I have also found higher mag scopes, even when not at their upper end, to suffer from a finicky eyebox. I cannot say why. I haven't owned many, partially because of that. @Carl ...what makes an optic's eyebox more or less user friendly?
I believe exit pupil is a large factor but know it isn't the only factor. Ilya Koshkin seems pretty knowledgeable on the subject, he hangs out at the Hide and other places.

It's common for hunting scopes to have 40-42mm objectives as 9x optics or 15x optics. In that situation the eyebox is going to favor the lower magnification.

For example, I have decent experience with the 3-12 LRHS, the 3-15 SWFA SS, and the 4.5-18 LRHS. They all have objectives in that range. I like them all at 12x decently but I feel they get noticeably less friendly as you exceed 12x, for the ones that can.

The popular PRS scopes basically all have 56mm objectives, and are friendly beyond 20x.

I will say the 4-16x42mm NF ATACR is remarkably good at 16x with a moderate objective size. It's a very good scope.
 
Eye relief is not the same thing as the size of the “eye box”.

Eye relief is the distance from the ocular lens that the exit pupil is focused at. So eye relief tells you how far from the scope your eye should be.

Your “eye box” is basically related to the diameter of the exit pupil at its focal point which is objective lens diameter/power.
 

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