[ShootingSight]

The answer has been discussed multiple times, which is why I thought it funny that the question got raised again, however, here is the answer:

For long guns, like M1, M14, Smallbore, match, palma, you want to get your distance prescription, if any, and add +0.50 diopters.

For shorter sight radius, like pistol iron sights, or AR15, you want to add +0.75.

These values represent the hyperfocal distance of the front sight such that you can see the sight without blurring out the target.

 

[JEFFJP_N_JJ]

The answer has been discussed multiple times, which is why I thought it funny that the question got raised again, however, here is the answer:

For long guns, like M1, M14, Smallbore, match, palma, you want to get your distance prescription, if any, and add +0.50 diopters.

For shorter sight radius, like pistol iron sights, or AR15, you want to add +0.75.

These values represent the hyperfocal distance of the front sight such that you can see the sight without blurring out the target.

Question!? What do you do Art when your NEW prescription is not any better than your OLD one and you still double or things in different planes?
I went back to my Optimologist and had the Dr re-check my precrisption which he said was fine!
Left lens was a bit off with my new glasses and he told me to go back to COSTCO and tell them to call him if any questions... The ones he told me are ok I have 'right' eye issues!

 

[ShootingSight]

My point was that you don't want your 'regular' prescription, you want your prescription with +0.50 or +0.75 added to the sphere power.

If you are seeing things double, I'd first propose a blinder for you non-shooting eye, in case it is a dominant eye issue. If you are seeing double with one eye, I'd imagine there is an error and that your astigmatism is 90 degrees out.